Pages using the property "Phenology"

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Abelmoschus esculentus +Flowering spring–fall.  +
Abietinella abietina +Capsules mature late summer.  +
Abildgaardia ovata +Fruiting all year.  +
Abronia alpina +Flowering summer.  +
Abronia ameliae +Flowering winter–spring.  +
Abronia ammophila +Flowering summer–fall.  +
Abronia angustifolia +Flowering spring–fall.  +
Abronia argillosa +Flowering spring–summer.  +
Abronia bigelovii +Flowering fall.  +
Abronia bolackii +Flowering spring–summer.  +
Abronia carletonii +Flowering spring–fall.  +
Abronia elliptica +Flowering spring–fall.  +
Abronia fragrans +Flowering spring–fall.  +
Abronia latifolia +Flowering spring–summer.  +
Abronia macrocarpa +Flowering spring, opportunistically after summer rains.  +
Abronia maritima +Flowering year-round.  +
Abronia mellifera +Flowering spring–fall.  +
Abronia nana var. covillei +Flowering spring–fall.  +
Abronia nana var. nana +Flowering spring–fall.  +
Abronia pogonantha +Flowering spring–summer.  +
Abronia turbinata +Flowering spring–fall.  +
Abronia umbellata var. acutalata +Flowering spring–fall.  +
Abronia umbellata var. breviflora +Flowering year-round.  +
Abronia umbellata var. umbellata +Flowering year-round.  +
Abronia villosa var. aurita +Flowering year-round.  +
Abronia villosa var. villosa +Flowering winter–summer.  +
Abutilon abutiloides +Flowering year-round.  +
Abutilon berlandieri +Flowering year-round.  +
Abutilon coahuilae +Flowering year-round.  +
Abutilon fruticosum +Flowering year-round.  +
Abutilon hirtum +Flowering year-round.  +
Abutilon hulseanum +Flowering winter–spring.  +
Abutilon hypoleucum +Flowering spring–fall.  +
Abutilon incanum +Flowering spring–fall.  +
Abutilon malacum +Flowering summer.  +
Abutilon mollicomum +Flowering late summer.  +
Abutilon palmeri +Flowering late winter–spring.  +
Abutilon parishii +Flowering late summer.  +
Abutilon parvulum +Flowering spring–fall.  +
Abutilon permolle +Flowering year-round.  +
Abutilon reventum +Flowering late summer.  +
Abutilon theophrasti +Flowering summer–fall.  +
Abutilon trisulcatum +Flowering winter–spring.  +
Abutilon wrightii +Flowering spring–fall.  +
Acaena novae-zelandiae +Flowering May–Jun.  +
Acaena pallida +Flowering May–Jun.  +
Acaena pinnatifida +Flowering Mar–Jun.  +
Acalypha alopecuroidea +Flowering and fruiting late summer–fall.  +
Acalypha arvensis +Flowering and fruiting summer–fall.  +
Acalypha australis +Flowering and fruiting late summer–fall.  +
Acalypha californica +Flowering and fruiting year-round, especially spring and fall.  +
Acalypha chamaedrifolia +Flowering and fruiting year-round, mainly spring–fall.  +
Acalypha deamii +Flowering and fruiting late summer–fall.  +
Acalypha gracilens +Flowering and fruiting mostly summer–fall.  +
Acalypha monococca +Flowering and fruiting summer–fall.  +
Acalypha monostachya +Flowering and fruiting spring–fall.  +
Acalypha neomexicana +Flowering and fruiting late summer–fall.  +
Acalypha ostryifolia +Flowering and fruiting summer–fall.  +
Acalypha phleoides +Flowering and fruiting spring–fall.  +
Acalypha poiretii +Flowering and fruiting late summer–fall.  +
Acalypha radians +Flowering and fruiting spring–fall.  +
Acalypha rhomboidea +Flowering and fruiting summer–fall.  +
Acalypha setosa +Flowering and fruiting summer–fall.  +
Acalypha virginica +Flowering and fruiting summer–fall.  +
Acalypha wilkesiana +Flowering spring–fall.  +
Acamptopappus shockleyi +Flowering Apr–Jun.  +
Acamptopappus sphaerocephalus var. hirtellus +Flowering Apr–Jun.  +
Acamptopappus sphaerocephalus var. sphaerocephalus +Flowering Mar–Jun.  +
Acanthocereus tetragonus +Flowering mid summer–fall.  +
Acanthoscyphus parishii var. abramsii +Flowering Jun–Aug.  +
Acanthoscyphus parishii var. cienegensis +Flowering Jun–Sep.  +
Acanthoscyphus parishii var. goodmaniana +Flowering May–Sep.  +
Acanthoscyphus parishii var. parishii +Flowering Jun–Oct.  +
Acanthospermum australe +Flowering year round, mostly Jul–Aug.  +
Acanthospermum hispidum +Flowering year round, mostly Aug–Oct.  +
Acanthospermum humile +Flowering all year.  +
Acaulon muticum var. muticum +Capsules mature late fall to spring.  +
Acaulon muticum var. rufescens +Capsules mature late fall to early spring.  +
Acaulon schimperianum +Capsules mature winter.  +
Acaulon triquetrum +Capsules mature late autumn-spring.  +
Achillea alpina +Flowering early Jul–early Sep.  +
Achillea millefolium +Flowering late Apr–early Jul (south), mid Jul–mid Sep (north).  +
Achillea nobilis +Flowering mid Jul–early Sep.  +
Achillea ptarmica +Flowering late Jun–mid Sep.  +
Achlys californica +Flowering spring–summer (Apr–Jul).  +
Achlys triphylla +Flowering spring–summer (Apr–Jul).  +
Achyrachaena mollis +Flowering Mar–Jun.  +
Achyranthes aspera var. aspera +Flowering summer.  +
Achyranthes aspera var. pubescens +Flowering summer.  +
Achyranthes japonica +Flowering summer.  +
Achyronychia cooperi +Flowering spring.  +
Acleisanthes acutifolia +Flowering spring–fall.  +
Acleisanthes angustifolia +Flowering late spring–early fall.  +
Acleisanthes anisophylla +Flowering spring–fall.  +
Acleisanthes chenopodioides +Flowering late spring–early fall.  +
Acleisanthes crassifolia +Flowering spring–fall.  +
Acleisanthes diffusa +Flowering late spring–late summer.  +
Acleisanthes lanceolata var. lanceolata +Flowering late spring–early fall.  +
Acleisanthes longiflora +Flowering Feb–Nov.  +
Acleisanthes nevadensis +Flowering spring–summer.  +
Acleisanthes obtusa +Flowering early spring–late fall.  +
Acleisanthes parvifolia +Flowering late spring–early fall.  +
Acleisanthes wrightii +Flowering spring–fall.  +
Acmella pusilla +Flowering May–Sep.  +
Acmella repens +Flowering Jan–Dec.  +
Acoelorraphe wrightii +Flowering spring–summer.  +
Aconitum columbianum subsp. columbianum +Flowering summer (Jul–Sep).  +
Aconitum columbianum subsp. viviparum +Flowering summer (Jul–Sep).  +
Aconitum delphiniifolium +Flowering summer (mid Jun–Sep).  +
Aconitum maximum subsp. maximum +Flowering summer (mid Jul–Sep).  +
Aconitum reclinatum +Flowering late spring–summer (Jun–Sep).  +
Aconitum uncinatum +Flowering late summer (mid Aug-late Sep).  +
Aconogonon alaskanum var. alaskanum +Flowering Jun–Aug.  +
Aconogonon alaskanum var. glabrescens +Flowering Jun–Aug.  +
Aconogonon davisiae var. davisiae +Flowering Jun–Aug.  +
Aconogonon davisiae var. glabrum +Flowering Jun–Aug.  +
Aconogonon phytolaccifolium var. glabrum +Flowering Jun–Aug.  +
Aconogonon phytolaccifolium var. phytolaccifolium +Flowering Jun–Aug.  +
Acorus americanus +Flowering late spring–mid summer.  +
Acorus calamus +Flowering early spring–early summer.  +
Acourtia microcephala +Flowering May–Jul.  +
Acourtia nana +Flowering (Mar–)Apr(–Jun).  +
Acourtia runcinata +Flowering year round (mostly Mar–Aug).  +
Acourtia thurberi +Flowering Oct–Nov.  +
Acourtia wrightii +Flowering Jun–Nov.  +
Acrocomia totai +Flowering in the summer.  +
Acroporium smallii +Capsules mature summer.  +
Acroptilon repens +Flowering late spring–summer (May–Sep).  +
Acrostichum aureum +Sporulating all year.  +
Actaea pachypoda +Flowering spring–early summer.  +
Actaea rubra +Flowering spring–early summer.  +
Adelia vaseyi +Flowering Jan–Jun, fruiting Jun.  +
Adenocaulon bicolor +Flowering Jun–Oct.  +
Adenophyllum cooperi +Flowering spring–fall.  +
Adenophyllum porophylloides +Flowering spring and fall.  +
Adenophyllum wrightii var. wrightii +Flowering fall.  +
Adenostoma fasciculatum var. fasciculatum +Flowering (Apr–)May–Jun(–Aug).  +
Adenostoma fasciculatum var. obtusifolium +Flowering (Apr–)May–Jun(–Aug).  +
Adenostoma fasciculatum var. prostratum +Flowering (Apr–)May–Jun(–Aug).  +
Adenostoma sparsifolium +Flowering Jul–Aug(–Sep).  +
Adiantum aleuticum +Sporulating summer–fall.  +
Adiantum capillus-veneris +Sporulating spring–summer.  +
Adiantum hispidulum +Sporulating summer–fall.  +
Adiantum jordanii +Sporulating early spring–midsummer.  +
Adiantum melanoleucum +Sporulating throughout the year.  +
Adiantum pedatum +Sporulating summer–fall.  +
Adiantum tenerum +Sporulating throughout the year.  +
Adiantum tricholepis +Sporulating late winter–early spring.  +
Adiantum viridimontanum +Sporulating summer–fall.  +
Adlumia fungosa +Flowering summer–early fall.  +
Adolphia californica +Flowering Dec–Apr(–May).  +
Adolphia infesta +Flowering Mar–Aug(–Sep).  +
Adonis aestivalis +Flowering spring–summer (May–Jul).  +
Adonis annua +Flowering spring–summer (Apr–Jun).  +
Adonis vernalis +Flowering spring (Apr–May).  +
Aeonium arboreum var. arboreum +Flowering spring.  +
Aeonium haworthii +Flowering late spring.  +
Agalinis aphylla +Flowering early Sep–mid Oct.  +
Agalinis aspera +Flowering Jul–Sep.  +
Agalinis auriculata +Flowering Aug–Sep.  +
Agalinis caddoensis +Flowering Oct.  +
Agalinis calycina +Flowering Aug–Sep.  +
Agalinis decemloba +Flowering Aug–mid Oct.  +
Agalinis densiflora +Flowering Aug–Sep.  +
Agalinis divaricata +Flowering early Sep–mid Oct.  +
Agalinis edwardsiana +Flowering Aug–Oct.  +
Agalinis fasciculata +Flowering year-round.  +
Agalinis filicaulis +Flowering mid Sep–early Nov.  +
Agalinis filifolia +Flowering Jun–Nov.  +
Agalinis flexicaulis +Flowering Sep–late Oct.  +
Agalinis gattingeri +Flowering mid Aug–Oct.  +
Agalinis georgiana +Flowering late Aug–late Sep(–Oct).  +
Agalinis harperi +Flowering late Sep–Oct.  +
Agalinis heterophylla +Flowering late Aug–early Oct.  +
Agalinis homalantha +Flowering late Aug–early Oct.  +
Agalinis laxa +Flowering Sep–Oct.  +
Agalinis linifolia +Flowering late Aug–early Oct.  +
Agalinis maritima var. grandiflora +Flowering year-round.  +
Agalinis maritima var. maritima +Flowering Jul–Sep.  +
Agalinis navasotensis +Flowering Sep–Oct.  +
Agalinis neoscotica +Flowering late Jul–early Sep.  +
Agalinis obtusifolia +Flowering Sep–late Oct.  +
Agalinis oligophylla +Flowering late Sep–mid Nov.  +
Agalinis plukenetii +Flowering late Sep–early Nov.  +
Agalinis pulchella +Flowering Sep–early Oct.  +
Agalinis purpurea var. parviflora +Flowering Jul–Sep.  +
Agalinis purpurea var. purpurea +Flowering Aug–Oct.  +
Agalinis setacea +Flowering Aug–Oct.  +
Agalinis skinneriana +Flowering Aug–early Oct.  +
Agalinis strictifolia +Flowering mid Jul–Oct.  +
Agalinis tenella +Flowering Sep–Oct.  +
Agalinis tenuifolia +Flowering (late Jul–)Aug–Nov.  +
Agalinis viridis +Flowering late Aug–Oct.  +
Agarista populifolia +Flowering early spring–spring.  +
Agave americana subsp. protamericana +Flowering early spring–early summer.  +
Agave americana var. americana +Flowering mid spring–early summer.  +
Agave americana var. expansa +Flowering late spring–early summer.  +
Agave asperrima var. asperrima +Flowering late spring–summer.  +
Agave chrysantha +Flowering late spring–summer.  +
Agave decipiens +Flowering mid fall–early winter.  +
Agave delamateri +Flowering early summer.  +
Agave deserti var. deserti +Flowering spring.  +
Agave deserti var. simplex +Flowering spring.  +
Agave desmettiana +Flowering late spring–early summer.  +
Agave gracilipes +Flowering summer–early fall.  +
Agave havardiana +Flowering summer–early fall.  +
Agave lechuguilla +Flowering mid spring–late summer.  +
Agave mckelveyana +Flowering mid spring–mid summer.  +
Agave murpheyi +Flowering late winter–spring.  +
Agave neglecta +Flowering early summer.  +
Agave palmeri +Flowering late spring–summer.  +
Agave parryi subsp. neomexicana +Flowering mid spring–early summer.  +
Agave parryi var. couesii +Flowering late spring–early summer.  +
Agave parryi var. huachucensis +Flowering mid spring–early summer.  +
Agave parryi var. parryi +Flowering mid spring–mid summer.  +
Agave parviflora subsp. parviflora +Flowering late spring–late summer.  +
Agave phillipsiana +Flowering early summer.  +
Agave schottii var. schottii +Flowering late spring–late summer.  +
Agave schottii var. treleasei +Flowering late spring–summer.  +
Agave shawii var. shawii +Flowering winter–mid spring.  +
Agave sisalana +Flowering winter–early spring.  +
Agave toumeyana var. bella +Flowering late spring.  +
Agave toumeyana var. toumeyana +Flowering late spring–summer.  +
Agave univittata +Flowering spring.  +
Agave utahensis +Flowering late winter–early summer  +
Agave utahensis subsp. kaibabensis +Flowering mid spring–early summer.  +
Agave utahensis subsp. utahensis +Flowering late winter–early summer  +
Agave utahensis var. eborispina +Flowering late winter–spring.  +
Agave utahensis var. utahensis +Flowering late winter–early summer.  +
Agave weberi +Flowering late spring–early summer.  +
Agave ×ajoensis +Flowering late spring–summer.  +
Agave ×arizonica +Flowering mid spring–early summer.  +
Agave ×glomeruliflora +Flowering mid spring–early fall.  +
Agdestis clematidea +Flowering summer–fall.  +
Ageratina adenophora +Flowering Mar–Aug(–Sep).  +
Ageratina altissima var. altissima +Flowering Jul–Oct(–Nov).  +
Ageratina altissima var. roanensis +Flowering Jul–Oct.  +
Ageratina aromatica +Flowering late Aug–Oct(–Nov).  +
Ageratina havanensis +Flowering mainly (Sep–)Oct–Nov(–Dec), also Apr–Jul.  +
Ageratina herbacea +Flowering (Jul–)Aug–Oct.  +
Ageratina jucunda +Flowering (Sep–)Oct–Dec(–Jan).  +
Ageratina lemmonii +Flowering Aug–Oct.  +
Ageratina luciae-brauniae +Flowering Aug–Oct.  +
Ageratina occidentalis +Flowering (Jun–)Jul–Sep.  +
Ageratina paupercula +Flowering Mar–May.  +
Ageratina rothrockii +Flowering (Jul–)Aug–Oct.  +
Ageratina shastensis +Flowering Jun–Oct.  +
Ageratina thyrsiflora +Flowering Sep–Nov.  +
Ageratina wrightii +Flowering (Jul–)Aug–Oct(–Nov).  +
Ageratum conyzoides +Flowering Jul–Aug.  +
Ageratum corymbosum +Flowering Jul–Oct.  +
Ageratum houstonianum +Flowering Jun–Aug.  +
Ageratum maritimum +Flowering year round.  +
Agnorhiza bolanderi +Flowering Mar–Apr(–May).  +
Agnorhiza elata +Flowering Jun–Jul(–Aug).  +
Agnorhiza invenusta +Flowering Jun–Jul.  +
Agnorhiza ovata +Flowering May–Jul(–Aug).  +
Agnorhiza reticulata +Flowering May–Jun.  +
Agoseris apargioides var. apargioides +Flowering Apr–May (year-round).  +
Agoseris apargioides var. eastwoodiae +Flowering April–May (year-round).  +
Agoseris apargioides var. maritima +Flowering Jul–Aug.  +
Agoseris aurantiaca var. aurantiaca +Flowering Jun–Sep.  +
Agoseris aurantiaca var. purpurea +Flowering Jun–Sep.  +
Agoseris glauca var. dasycephala +Flowering Jul–Aug.  +
Agoseris glauca var. glauca +Flowering May–Sep.  +
Agoseris grandiflora var. grandiflora +Flowering Mar–Oct.  +
Agoseris grandiflora var. leptophylla +Flowering Mar–Oct.  +
Agoseris heterophylla var. cryptopleura +Flowering Mar–Sep.  +
Agoseris heterophylla var. heterophylla +Flowering Mar–Sep.  +
Agoseris heterophylla var. quentinii +Flowering Mar–Jun.  +
Agoseris hirsuta +Flowering mostly Apr–Jun, rarely Sep–Dec.  +
Agoseris monticola +Flowering Jul–Aug.  +
Agoseris parviflora +Flowering Apr–Aug.  +
Agoseris retrorsa +Flowering Apr–Aug.  +
Agoseris ×elata +Flowering Jun–Sep.  +
Agrimonia gryposepala +Flowering Jul–mid Aug[–Mar].  +
Agrimonia incisa +Flowering late Jul–Nov.  +
Agrimonia microcarpa +Flowering late Jul–Sep.  +
Agrimonia parviflora +Flowering mid Jul–early Sep.  +
Agrimonia pubescens +Flowering mid Jul–Sep.  +
Agrimonia rostellata +Flowering Jul–mid Sep.  +
Agrimonia striata +Flowering late Jun–Aug(–mid Sep).  +
Agrostemma githago var. githago +Flowering spring–summer.  +
Akebia quinata +Flowering spring, fruiting fall (Sep–Oct).  +
Alcea rosea +Flowering May–Oct  +, fruiting Jun–Oct.  +
Alcea rugosa +Flowering May–Oct  +, fruiting Jun–Oct.  +
Alchemilla alpina +Flowering mid Jun–mid Sep.  +
Alchemilla filicaulis subsp. filicaulis +Flowering late Jun–Sep.  +
Alchemilla filicaulis subsp. vestita +Flowering late Jun–Aug.  +
Alchemilla glabra +Flowering Jul–Aug.  +
Alchemilla glaucescens +Flowering Jun–Aug.  +
Alchemilla glomerulans +Flowering late Jun–Sep.  +
Alchemilla micans +Flowering late May–Sep.  +
Alchemilla mollis +Flowering late Jul–Sep.  +
Alchemilla monticola +Flowering late May–Sep.  +
Alchemilla subcrenata +Flowering Jun–Sep.  +
Alchemilla venosa +Flowering late Jun–Aug.  +
Alchemilla wichurae +Flowering Jul.  +
Alchemilla xanthochlora +Flowering late May–Sep.  +
Aletris aurea +Flowering late spring–mid summer.  +
Aletris bracteata +Flowering year round.  +
Aletris farinosa +Flowering late spring–mid summer.  +
Aletris lutea +Flowering spring.  +
Aletris obovata +Flowering late spring–mid summer.  +
Alisma gramineum +Flowering summer–fall.  +
Alisma lanceolatum +Flowering and fruiting summer–fall.  +
Alisma plantago-aquatica +Flowering and fruiting late summer.  +
Alisma subcordatum +Flowering spring–fall.  +
Alisma triviale +Flowering spring–fall.  +
Allenrolfea occidentalis +Flowering mid summer–late fall.  +
Alliaria petiolata +Flowering Apr–May.  +
Allionia choisyi +Flowering late spring–early fall [year-round].  +
Allionia incarnata var. incarnata +Flowering year-round, primarily early spring–late fall.  +
Allionia incarnata var. villosa +Flowering early spring–late fall [year-round].  +
Allium aaseae +Flowering Apr–May.  +
Allium abramsii +Flowering May–Jul.  +
Allium acuminatum +Flowering Apr–Jul.  +
Allium ampeloprasum +Flowering Apr–Jul.  +
Allium amplectens +Flowering Apr–Jul.  +
Allium anceps +Flowering Apr–May.  +
Allium atrorubens var. atrorubens +Flowering May–Jun.  +
Allium atrorubens var. cristatum +Flowering late Apr–Jun.  +
Allium bigelovii +Flowering late Mar–May.  +
Allium bisceptrum +Flowering May–Jul.  +
Allium bolanderi var. bolanderi +Flowering late May–early Aug.  +
Allium bolanderi var. mirabile +Flowering late May–early Jul.  +
Allium brandegeei +Flowering late Apr–Jul.  +
Allium brevistylum +Flowering Jun–Aug.  +
Allium burlewii +Flowering late Apr–Jul.  +
Allium campanulatum +Flowering late May–Aug.  +
Allium canadense var. canadense +Flowering Apr–Jul.  +
Allium canadense var. ecristatum +Flowering Mar–early Apr.  +
Allium canadense var. fraseri +Flowering Apr–Jun.  +
Allium canadense var. hyacinthoides +Flowering late Mar–Apr.  +
Allium canadense var. lavendulare +Flowering May–Jul.  +
Allium canadense var. mobilense +Flowering Apr–May.  +
Allium cepa +Flowering Jun–Aug.  +
Allium cernuum +Flowering Jul–Oct.  +
Allium columbianum +Flowering May–Jul.  +
Allium constrictum +Flowering May–Jul.  +
Allium coryi +Flowering Apr–May.  +
Allium cratericola +Flowering Mar–Jun.  +
Allium crenulatum +Flowering late May–Jul.  +
Allium crispum +Flowering late Mar–Jun.  +
Allium cuthbertii +Flowering May–early Jun.  +
Allium denticulatum +Flowering mid Apr–mid Jul.  +
Allium diabolense +Flowering mid Apr–Jun.  +
Allium dichlamydeum +Flowering May–Jul.  +
Allium dictuon +Flowering Jun–Jul.  +
Allium douglasii +Flowering May–Jul.  +
Allium drummondii +Flowering Mar–Jun.  +
Allium elmendorfii +Flowering Mar–early Apr.  +
Allium falcifolium +Flowering Apr–Jun.  +
Allium fibrillum +Flowering May–Jul.  +
Allium fimbriatum var. fimbriatum +Flowering Apr–Jun.  +
Allium fimbriatum var. mohavense +Flowering Apr–May.  +
Allium fimbriatum var. purdyi +Flowering late Apr–Jun.  +
Allium fistulosum +Flowering Jul–Aug.  +
Allium geyeri var. geyeri +Flowering May–Sep.  +
Allium geyeri var. tenerum +Flowering May–Sep.  +
Allium gooddingii +Flowering Jun–Sep.  +
Allium haematochiton +Flowering Mar–May.  +
Allium hickmanii +Flowering Mar–May.  +
Allium hoffmanii +Flowering Jun–Jul.  +
Allium howellii var. clokeyi +Flowering May–Jun.  +
Allium howellii var. howellii +Flowering Mar–Apr.  +
Allium howellii var. sanbenitense +Flowering Apr–May.  +
Allium hyalinum +Flowering Mar–May.  +
Allium jepsonii +Flowering late May–early Jul.  +
Allium kunthii +Flowering Jul–Sep.  +
Allium lacunosum var. davisiae +Flowering Apr–May.  +
Allium lacunosum var. kernensis +Flowering Apr–May.  +
Allium lacunosum var. lacunosum +Flowering Apr–Jun.  +
Allium lacunosum var. micranthum +Flowering Apr–Jun.  +
Allium lemmonii +Flowering May–Jun.  +
Allium macropetalum +Flowering late Mar–Jun.  +
Allium macrum +Flowering Apr–May.  +
Allium madidum +Flowering May–Jul.  +
Allium membranaceum +Flowering May–Jun.  +
Allium monticola +Flowering late May–Jul.  +
Allium munzii +Flowering Apr–mid May.  +
Allium neapolitanum +Flowering Mar–Apr.  +
Allium nevadense +Flowering Apr–Jun.  +
Allium nevii +Flowering May–Jul.  +
Allium nigrum +Flowering Jun.  +
Allium obtusum var. conspicuum +Flowering May–Jun.  +
Allium obtusum var. obtusum +Flowering May–Jun.  +
Allium oleraceum +Flowering late Jul–Aug.  +
Allium paniculatum var. paniculatum +Flowering Jun–Jul.  +
Allium parishii +Flowering Apr–May.  +
Allium parryi +Flowering May–Jul.  +
Allium parvum +Flowering late Apr–Jun.  +
Allium passeyi +Flowering Jun.  +
Allium peninsulare var. franciscanum +Flowering May–Jun.  +
Allium peninsulare var. peninsulare +Flowering Apr–May.  +
Allium perdulce var. perdulce +Flowering Apr–Jun.  +
Allium perdulce var. sperryi +Flowering Mar–Apr.  +
Allium platycaule +Flowering May–Jun.  +
Allium plummerae +Flowering Jun–Sep.  +
Allium praecox +Flowering Mar–May.  +
Allium punctum +Flowering May–Jun.  +
Allium rhizomatum +Flowering Jul–Sep.  +
Allium robinsonii +Flowering Apr–May.  +
Allium rotundum +Flowering May–Jul.  +
Allium runyonii +Flowering Mar–Apr.  +
Allium sanbornii var. congdonii +Flowering Jun–Jul.  +
Allium sanbornii var. sanbornii +Flowering late Jun–Aug.  +
Allium sativum var. sativum +Flowering Jun–Jul.  +
Allium schoenoprasum +Flowering Jun–Aug.  +
Allium scilloides +Flowering Mar–Apr.  +
Allium serra +Flowering Apr–May.  +
Allium sharsmithiae +Flowering Apr–May.  +
Allium shevockii +Flowering Jun–Jul.  +
Allium simillimum +Flowering Apr–Jun.  +
Allium siskiyouense +Flowering late Apr–Jun.  +
Allium speculae +Flowering Jun.  +
Allium stellatum +Flowering Jul–Oct.  +
Allium textile +Flowering May–Jun.  +
Allium tolmiei var. persimile +Flowering Apr–Jul.  +
Allium tolmiei var. tolmiei +Flowering Apr–Jul.  +
Allium tribracteatum +Flowering Mar–May.  +
Allium tricoccum var. burdickii +Flowering early Jun.  +
Allium tricoccum var. tricoccum +Flowering Jul–Aug.  +
Allium triquetrum +Flowering Mar–Apr.  +
Allium tuberosum +Flowering Jul–Aug.  +
Allium tuolumnense +Flowering Mar–May.  +
Allium unifolium +Flowering May–Jun.  +
Allium validum +Flowering Jun–Aug.  +
Allium victorialis +Flowering Jul–Aug.  +
Allium vineale +Flowering Jun–Aug.  +
Allium yosemitense +Flowering May–Jun.  +
Allotropa virgata +Flowering late spring–summer.  +
Allowissadula holosericea +Flowering May–Nov.  +
Allowissadula lozanoi +Flowering May–Oct.  +
Almutaster pauciflorus +Flowering spring–fall.  +
Alnus glutinosa +Flowering early spring.  +
Alnus incana subsp. rugosa +Flowering early spring.  +
Alnus incana subsp. tenuifolia +Flowering early spring.  +
Alnus maritima +Flowering late summer–early fall.  +
Alnus oblongifolia +Flowering early spring.  +
Alnus rhombifolia +Flowering early spring.  +
Alnus rubra +Flowering early spring.  +
Alnus serrulata +Flowering early spring.  +
Alnus viridis subsp. crispa +Flowering spring.  +
Alnus viridis subsp. fruticosa +Flowering spring.  +
Alnus viridis subsp. sinuata +Flowering spring.  +
Aloe vera +Flowering spring–winter, occasionally at other times.  +
Aloe ×schonlandii +Flowering spring.  +
Aloina aloides var. ambigua +Capsules mature Jan–May.  +
Aloina bifrons +Capsules mature Jan–Jul(-Aug).  +
Aloina brevirostris +Capsules mature (Mar-)May–Aug.  +
Aloina hamulus +Sporophytes unknown in flora area.  +
Aloina rigida var. rigida +Capsules mature Jun–Aug(-Oct).  +
Alophia drummondii +Flowering mostly May–Jul(–Sep).  +
Alpinia zerumbet +Flowering spring–summer (May–Sep).  +
Alsia californica +Capsules mature spring.  +
Alstroemeria pulchella +Flowering mid spring–early summer.  +
Alternanthera brasiliana +Flowering spring.  +
Alternanthera caracasana +Flowering summer–fall.  +
Alternanthera ficoidea var. bettzickiana +Flowering late winter.  +
Alternanthera flavescens +Flowering year-round.  +
Alternanthera maritima +Flowering winter–spring.  +
Alternanthera paronychioides +Flowering spring–late fall, year-round in far south.  +
Alternanthera philoxeroides +Flowering early spring–summer.  +
Alternanthera pungens +Flowering summer–fall.  +
Alternanthera sessilis +Flowering summer–early fall.  +
Althaea armeniaca +Flowering summer–fall.  +
Althaea cannabina +Flowering summer.  +
Althaea hirsuta +Flowering spring–summer.  +
Althaea officinalis +Flowering summer–fall.  +
Alvaradoa amorphoides subsp. psilophylla +Flowering and fruiting year-round.  +
Alyssum alyssoides +Flowering May–Jul.  +
Alyssum desertorum +Flowering Apr–Jul.  +
Alyssum murale +Flowering May–Jul.  +
Alyssum obovatum +Flowering May–Jul.  +
Alyssum simplex +Flowering Apr–Jun.  +
Alyssum szowitsianum +Flowering May.  +
Amaranthus acanthochiton +Flowering summer–fall.  +
Amaranthus albus +Flowering summer–fall.  +
Amaranthus arenicola +Flowering summer–fall.  +
Amaranthus australis +Flowering summer–fall.  +
Amaranthus blitoides +Flowering summer–fall.  +
Amaranthus blitum +Flowering summer–fall (almost year-round in tropics, subtropics).  +
Amaranthus californicus +Flowering summer–fall.  +
Amaranthus cannabinus +Flowering summer–fall.  +
Amaranthus caudatus +Flowering summer–fall.  +
Amaranthus crassipes +Flowering summer and fall.  +
Amaranthus crispus +Flowering summer–fall.  +
Amaranthus cruentus +Flowering summer–fall.  +
Amaranthus deflexus +Flowering summer–fall.  +
Amaranthus dubius +Flowering summer–fall in tropics, various seasons in subtropics.  +
Amaranthus fimbriatus +Flowering summer–fall (in arid regions mostly after summer rains).  +
Amaranthus floridanus +Flowering late spring–fall.  +
Amaranthus graecizans +Flowering summer–fall.  +
Amaranthus greggii +Flowering summer–fall.  +
Amaranthus hybridus +Flowering summer–fall.  +
Amaranthus hypochondriacus +Flowering summer–fall.  +
Amaranthus muricatus +Flowering summer–fall.  +
Amaranthus obcordatus +Flowering summer–fall.  +
Amaranthus palmeri +Flowering summer–fall, occasionally spring–winter in southern part of its native range.  +
Amaranthus polygonoides +Flowering summer–fall.  +
Amaranthus powellii +Flowering summer–fall.  +
Amaranthus pumilus +Flowering summer–fall.  +
Amaranthus retroflexus +Flowering summer–fall.  +
Amaranthus scleropoides +Flowering summer–fall.  +
Amaranthus spinosus +Flowering summer–fall.  +
Amaranthus tamaulipensis +Flowering spring–fall.  +
Amaranthus thunbergii +Flowering summer–fall.  +
Amaranthus torreyi +Flowering summer–fall.  +
Amaranthus tricolor +Flowering summer–fall.  +
Amaranthus tuberculatus +Flowering summer–fall.  +
Amaranthus viridis +Flowering summer–fall.  +
Amaranthus viscidulus +Flowering summer–fall.  +
Amaranthus watsonii +Flowering late winter–spring, summer–fall.  +
Amaranthus wrightii +Flowering summer–fall.  +
Amauriopsis dissecta +Flowering (Jun–)Aug–Sep(–Oct).  +
Amberboa moschata +Flowering winter–early summer (Jan–Jul).  +
Amblyolepis setigera +Flowering (Jan–)Mar–May(–Sep).  +
Amblyopappus pusillus +Flowering spring.  +
Ambrosia acanthicarpa +Flowering (Apr–)Jul–Nov.  +
Ambrosia ambrosioides +Flowering Mar–May.  +
Ambrosia artemisiifolia +Flowering Jul–Oct.  +
Ambrosia bidentata +Flowering Jul–Oct.  +
Ambrosia chamissonis +Flowering Apr–Nov.  +
Ambrosia cheiranthifolia +Flowering Jun–Nov.  +
Ambrosia chenopodiifolia +Flowering Mar–Apr.  +
Ambrosia confertiflora +Flowering (May–)Sep–Dec.  +
Ambrosia cordifolia +Flowering Mar–Apr.  +
Ambrosia deltoidea +Flowering Feb–May.  +
Ambrosia dumosa +Flowering Mar–May(–Dec).  +
Ambrosia eriocentra +Flowering Apr–May(–Jul).  +
Ambrosia grayi +Flowering Aug–Sep.  +
Ambrosia hispida +Flowering Apr.  +
Ambrosia ilicifolia +Flowering Jan–Apr.  +
Ambrosia linearis +Flowering Jul.  +
Ambrosia monogyra +Flowering (May–)Aug–Nov.  +
Ambrosia psilostachya +Flowering Jul–Oct(–Dec).  +
Ambrosia pumila +Flowering May–Jun(–Oct).  +
Ambrosia salsola +Flowering Mar–May(–Jun).  +
Ambrosia tomentosa +Flowering Jun–Sep.  +
Ambrosia trifida +Flowering Jul–Nov.  +
Amelanchier alnifolia var. alnifolia +Flowering May–Jul  +, fruiting Jul–Aug.  +
Amelanchier alnifolia var. pumila +Flowering May–Jun  +, fruiting Jul–Sep.  +
Amelanchier alnifolia var. semiintegrifolia +Flowering Mar–Jun  +, fruiting Jun–Aug.  +
Amelanchier amabilis +Flowering May–Jun  +, fruiting Jul–Aug.  +
Amelanchier arborea +Flowering Feb–May  +, fruiting May–Jul.  +
Amelanchier bartramiana +Flowering May–Aug  +, fruiting Jul–Sep.  +
Amelanchier canadensis var. canadensis +Flowering Mar–May  +, fruiting Jun–Jul.  +
Amelanchier canadensis var. obovalis +Flowering Mar–May  +, fruiting May–Jun.  +
Amelanchier cusickii +Flowering Mar–Jul  +, fruiting May–Aug.  +
Amelanchier fernaldii +Flowering Jun–Jul  +, fruiting Jul–Aug.  +
Amelanchier gaspensis +Flowering May–Jun  +, fruiting Jul–Sep.  +
Amelanchier humilis +Flowering Apr–May  +, fruiting Jul–Aug.  +
Amelanchier interior +Flowering May–Jun  +, fruiting Jul–Aug.  +
Amelanchier intermedia +Flowering May–Jun  +, fruiting Jun–Aug.  +
Amelanchier laevis +Flowering Apr–Jun  +, fruiting Jun–Jul.  +
Amelanchier nantucketensis +Flowering Mar–May  +, fruiting Jun–Jul.  +
Amelanchier nitens +Flowering Apr–Jun  +, fruiting Jun–Jul.  +
Amelanchier pallida +Flowering Apr–Jun  +, fruiting Jul–Sep.  +
Amelanchier sanguinea +Flowering May–Jun  +, fruiting Jul–Aug.  +
Amelanchier spicata +Flowering Apr–Jun  +, fruiting Jul–Aug.  +
Amelanchier utahensis +Flowering Apr–May  +, fruiting Jul–Sep.  +
Amerorchis rotundifolia +Flowering Jun–Jul.  +
Amianthium muscitoxicum +Flowering late spring–summer.  +
Amoreuxia gonzalezii +Flowering Jul–Sep.  +
Amoreuxia palmatifida +Flowering Jun–Sep  +, fruiting Jul–Oct.  +
Amoreuxia wrightii +Flowering May–Jul(–Oct).  +
Ampelaster carolinianus +Flowering peak late fall–winter, year round (Fla).  +
Ampelopsis aconitifolia +Flowering May–Aug  +, fruiting Jun–Oct.  +
Ampelopsis cordata +Flowering late Apr–Jun  +, fruiting Jul–Sep.  +
Ampelopsis glandulosa +Flowering late May–Jul  +, fruiting Jul–Oct.  +
Amphiachyris amoena +Flowering late Sep–Oct.  +
Amphiachyris dracunculoides +Flowering Jul–Nov.  +
Amphipappus fremontii var. fremontii +Flowering Mar–May.  +
Amphipappus fremontii var. spinosus +Flowering Mar–May.  +
Amphiscirpus nevadensis +Fruiting summer.  +
Anacamptodon splachnoides +Capsules mature (Jan-)Apr–Oct(-Dec).  +
Anacolia menziesii +Capsules mature Feb–Aug.  +
Anagallis arvensis +Flowering spring–summer.  +
Anagallis minima +Flowering spring–fall.  +
Anagallis monelli +Flowering spring–fall.  +
Anagallis pumila +Flowering spring–early winter.  +
Anaphalis margaritacea +Flowering Jul–Oct (sporadically longer).  +
Ancistrocactus brevihamatus +Flowering Jan–Mar.  +
Ancistrocactus scheeri +Flowering Nov–Mar.  +
Ancistrocarphus filagineus +Flowering and fruiting mid Mar–late Jun.  +
Ancistrocarphus keilii +Flowering and fruiting Mar–Apr.  +
Andreaeobryum macrosporum +Capsules mature late summer.  +
Andromeda polifolia var. latifolia +Flowering May–Jul(-Sep)  +, fruiting Jun–Sep.  +
Andromeda polifolia var. polifolia +Flowering May–Aug  +, fruiting Jun–Sep.  +
Androsace chamaejasme subsp. lehmanniana +Flowering summer.  +
Androsace elongata subsp. acuta +Flowering early-mid summer.  +
Androsace filiformis +Flowering early-mid summer.  +
Androsace occidentalis +Flowering early-mid summer.  +
Androsace septentrionalis +Flowering spring–early fall.  +
Androstephium breviflorum +Flowering spring (Mar–Jun).  +
Androstephium coeruleum +Flowering spring (Feb–May).  +
Anelsonia eurycarpa +Flowering Jun–Jul.  +
Anemone acutiloba +Flowering spring.  +
Anemone americana +Flowering spring.  +
Anemone berlandieri +Flowering winter–spring (Feb–Apr).  +
Anemone canadensis +Flowering spring–summer (May–Aug).  +
Anemone caroliniana +Flowering winter–spring (Feb–Apr).  +
Anemone cylindrica +Flowering summer (Jun–Jul).  +
Anemone deltoidea +Flowering spring–summer (Apr–Jul).  +
Anemone drummondii var. drummondii +Flowering summer (Jun–Aug).  +
Anemone drummondii var. lithophila +Flowering summer (Jun–Aug).  +
Anemone edwardsiana var. edwardsiana +Flowering winter–spring (Feb–Apr).  +
Anemone edwardsiana var. petraea +Flowering winter–spring (Feb–Apr).  +
Anemone grayi +Flowering winter–early summer (Feb–Jun).  +
Anemone lancifolia +Flowering spring–summer (Apr–Jun).  +
Anemone lyallii +Flowering spring–summer (Mar–Jul).  +
Anemone multiceps +Flowering spring–summer (May–Jul).  +
Anemone multifida var. multifida +Flowering spring–summer (Apr–Jul).  +
Anemone multifida var. saxicola +Flowering summer (Jun–Aug).  +
Anemone multifida var. stylosa +Flowering summer (Jul–Aug).  +
Anemone multifida var. tetonensis +Flowering spring–summer (Mar–Aug).  +
Anemone narcissiflora var. monantha +Flowering spring–summer (May–Jul).  +
Anemone narcissiflora var. villosissima +Flowering spring–summer (May–Aug).  +
Anemone narcissiflora var. zephyra +Flowering summer (Jun–Aug).  +
Anemone occidentalis +Flowering spring–summer (May–Aug/Sep).  +
Anemone okennonii +Flowering spring (Mar–Apr).  +
Anemone oregana var. felix +Flowering spring (Apr–Jun).  +
Anemone oregana var. oregana +Flowering spring (Mar–Jun).  +
Anemone parviflora +Flowering spring–summer (May–Aug).  +
Anemone patens var. multifida +Flowering spring–summer (Apr–Aug).  +
Anemone piperi +Flowering spring–summer (Apr–Aug).  +
Anemone quinquefolia var. minima +Flowering spring (Apr–May).  +
Anemone quinquefolia var. quinquefolia +Flowering spring–early summer (Mar–Jun).  +
Anemone richardsonii +Flowering spring–summer (May–Aug).  +
Anemone tuberosa +Flowering spring (Apr–May).  +
Anemone virginiana var. alba +Flowering spring–summer (May–Jul).  +
Anemone virginiana var. cylindroidea +Flowering summer (Jun–Aug).  +
Anemone virginiana var. virginiana +Flowering summer (Jun–Aug).  +
Anemopsis californica +Flowering early spring–summer.  +
Angelonia gardneri +Flowering May–Oct.  +
Anisocarpus madioides +Flowering Apr–Sep.  +
Anisocarpus scabridus +Flowering Jun–Sep.  +
Anisocoma acaulis +Flowering Mar–May.  +
Annona glabra +Flowering spring–early summer.  +
Annona squamosa +Flowering spring–early summer.  +
Anoda abutiloides +Flowering spring–fall.  +
Anoda crenatiflora +Flowering fall.  +
Anoda cristata +Flowering summer–fall.  +
Anoda lanceolata +Flowering summer–fall.  +
Anoda pentaschista +Flowering late summer–mid winter.  +
Anoda reticulata +Flowering late summer.  +
Anoda thurberi +Flowering late summer–early fall.  +
Anomobryum concinnatum +Capsules mature Jul–Sep.  +
Anomobryum julaceum +Capsules mature Jun–Sep.  +
Anomodon attenuatus +Capsules mature early-mid fall.  +
Anomodon minor +Capsules mature early fall.  +
Anomodon rostratus +Capsules mature early-mid fall.  +
Anomodon rugelii +Capsules mature mid fall.  +
Anomodon viticulosus +Capsules mature early-mid fall.  +
Anredera cordifolia +Flowering late summer–fall.  +
Anredera vesicaria +Flowering late summer–fall.  +
Antennaria alpina +Flowering mid–late summer.  +
Antennaria anaphaloides +Flowering summer.  +
Antennaria arcuata +Flowering summer.  +
Antennaria argentea +Flowering summer.  +
Antennaria aromatica +Flowering mid summer.  +
Antennaria corymbosa +Flowering early–mid summer.  +
Antennaria densifolia +Flowering summer.  +
Antennaria dimorpha +Flowering early–mid spring.  +
Antennaria dioica +Flowering summer.  +
Antennaria flagellaris +Flowering mid–late spring.  +
Antennaria friesiana subsp. alaskana +Flowering summer.  +
Antennaria friesiana subsp. friesiana +Flowering summer.  +
Antennaria friesiana subsp. neoalaskana +Flowering summer.  +
Antennaria geyeri +Flowering summer.  +
Antennaria howellii subsp. canadensis +Flowering mid spring–early summer.  +
Antennaria howellii subsp. howellii +Flowering mid spring–early summer.  +
Antennaria howellii subsp. neodioica +Flowering mid spring–early summer.  +
Antennaria howellii subsp. petaloidea +Flowering mid spring–early summer.  +
Antennaria lanata +Flowering summer.  +
Antennaria luzuloides subsp. aberrans +Flowering summer.  +
Antennaria luzuloides subsp. luzuloides +Flowering summer.  +
Antennaria marginata +Flowering summer.  +
Antennaria media +Flowering summer.  +
Antennaria microphylla +Flowering early–mid summer.  +
Antennaria monocephala subsp. angustata +Flowering summer.  +
Antennaria monocephala subsp. monocephala +Flowering summer.  +
Antennaria neglecta +Flowering early–mid spring.  +
Antennaria parlinii subsp. fallax +Flowering early–mid spring.  +
Antennaria parlinii subsp. parlinii +Flowering early–mid spring.  +
Antennaria parvifolia +Flowering late spring–summer.  +
Antennaria plantaginifolia +Flowering mid–late spring.  +
Antennaria pulchella +Flowering summer.  +
Antennaria pulcherrima subsp. eucosma +Flowering summer.  +
Antennaria pulcherrima subsp. pulcherrima +Flowering summer.  +
Antennaria racemosa +Flowering summer.  +
Antennaria rosea subsp. arida +Flowering summer.  +
Antennaria rosea subsp. confinis +Flowering summer.  +
Antennaria rosea subsp. pulvinata +Flowering summer.  +
Antennaria rosea subsp. rosea +Flowering summer.  +
Antennaria rosulata +Flowering summer.  +
Antennaria soliceps +Flowering summer.  +
Antennaria solitaria +Flowering early–mid spring.  +
Antennaria stenophylla +Flowering in late spring–early summer.  +
Antennaria suffrutescens +Flowering early summer.  +
Antennaria umbrinella +Flowering summer.  +
Antennaria virginica +Flowering early–mid spring.  +
Anthemis arvensis +Flowering May–Jul(–Sep).  +
Anthemis cotula +Flowering (Apr–)May–Aug(–Oct).  +
Antigonon leptopus +Flowering year-round.  +
Antirrhinum majus +Flowering May–Oct.  +
Anulocaulis annulatus +Flowering late winter–late summer, occasionally mid fall.  +
Anulocaulis eriosolenus +Flowering late spring-mid fall.  +
Anulocaulis leiosolenus var. gypsogenus +Flowering late spring–early fall.  +
Anulocaulis leiosolenus var. howardii +Flowering late spring–early fall.  +
Anulocaulis leiosolenus var. lasianthus +Flowering late spring–early fall.  +
Anulocaulis leiosolenus var. leiosolenus +Flowering late spring–early fall.  +
Anulocaulis reflexus +Flowering late spring–early fall.  +
Aongstroemia longipes +Capsules mature late summer.  +
Apacheria chiricahuensis +Flowering Apr–Nov.  +
Aphanes arvensis +Flowering Apr–May.  +
Aphanes australis +Flowering Mar–May.  +
Aphanes occidentalis +Flowering Mar–Jun.  +
Aphanisma blitoides +Flowering summer–early fall.  +
Aphanorrhegma serratum +Capsules mature (Jul) Sep–Dec.  +
Aphanostephus pilosus +Flowering May–Jul.  +
Aphanostephus ramosissimus var. humilis +Flowering Apr–Jun(–Oct).  +
Aphanostephus ramosissimus var. ramosissimus +Flowering (Feb–)Apr–Jul(–Sep).  +
Aphanostephus riddellii +Flowering Mar–Aug(–Oct).  +
Aphanostephus skirrhobasis var. kidderi +Flowering Mar–Jun(–Aug).  +
Aphanostephus skirrhobasis var. skirrhobasis +Flowering (Mar–)Apr–Jul(–Aug).  +
Aphanostephus skirrhobasis var. thalassius +Flowering (Feb–)Apr–Dec.  +
Aphragmus eschscholtzianus +Flowering Jun–Jul.  +
Aplectrum hyemale +Flowering late spring.  +
Aplodon wormskioldii +Capsules mature summer.  +
Apodanthera undulata var. undulata +Flowering May–Sep.  +
Aponogeton distachyos +Flowering late winter–spring (Mar–Apr), fall (Oct–Nov).  +
Aptenia cordifolia +Flowering spring–fall.  +
Apteria aphylla +Flowering late summer–fall.  +
Aquilegia barnebyi +Flowering summer (Jun–Jul).  +
Aquilegia brevistyla +Flowering summer (Jun–Aug).  +
Aquilegia canadensis +Flowering spring–summer (Mar–Jun).  +
Aquilegia chaplinei +Flowering summer (Jul–Aug).  +
Aquilegia chrysantha +Flowering spring–summer (Apr–Sep).  +
Aquilegia coerulea var. alpina +Flowering summer (Jun–Aug).  +
Aquilegia coerulea var. coerulea +Flowering summer (mid Jun-early Sep).  +
Aquilegia coerulea var. ochroleuca +Flowering summer (late Jun–Aug).  +
Aquilegia coerulea var. pinetorum +Flowering spring–summer (May–Sep).  +
Aquilegia desertorum +Flowering spring–fall (May–Oct).  +
Aquilegia elegantula +Flowering spring–summer (May–Jul).  +
Aquilegia eximia +Flowering spring–summer (May–Aug).  +
Aquilegia flavescens +Flowering summer (Jun–Aug).  +
Aquilegia formosa var. formosa +Flowering spring–summer (Apr–Aug).  +
Aquilegia formosa var. hypolasia +Flowering summer (Jun–Aug).  +
Aquilegia formosa var. truncata +Flowering spring–summer (Apr–Aug).  +
Aquilegia hinckleyana +Flowering spring (Mar–Apr).  +
Aquilegia jonesii +Flowering summer (Jun–Jul).  +
Aquilegia laramiensis +Flowering summer (Jun–Jul).  +
Aquilegia longissima +Flowering summer (Jul–Sep).  +
Aquilegia micrantha +Flowering spring–summer (Apr–Sep).  +
Aquilegia pubescens +Flowering summer (Jun–Aug).  +
Aquilegia saximontana +Flowering summer (Jul–Aug).  +
Aquilegia scopulorum +Flowering summer (Jun–Aug).  +
Aquilegia shockleyi +Flowering spring–summer (Apr–Aug).  +
Aquilegia vulgaris +Flowering spring–summer (May–Jul).  +
Arabidopsis arenicola +Flowering Jun–Aug.  +
Arabidopsis arenosa subsp. arenosa +Flowering Jul.  +
Arabidopsis lyrata subsp. kamchatica +Flowering Jun–Jul.  +
Arabidopsis lyrata subsp. lyrata +Flowering Apr–Jul.  +
Arabidopsis lyrata subsp. petraea +Flowering Jun–Jul.  +
Arabidopsis thaliana +Flowering Feb–May.  +
Arabis aculeolata +Flowering Mar–May(-Jun).  +
Arabis alpina +Flowering Jun–Aug.  +
Arabis blepharophylla +Flowering Mar–Apr.  +
Arabis caucasica +Flowering Jun–Aug.  +
Arabis crucisetosa +Flowering Apr–Jun.  +
Arabis eschscholtziana +Flowering (Apr-)May–Jul.  +
Arabis furcata +Flowering May–Jul(-Aug).  +
Arabis georgiana +Flowering Mar–Apr.  +
Arabis mcdonaldiana +Flowering May–Jun.  +
Arabis modesta +Flowering Mar–Apr(-May).  +
Arabis nuttallii +Flowering Apr–Aug.  +
Arabis olympica +Flowering Aug.  +
Arabis oregana +Flowering Apr–May.  +
Arabis patens +Flowering Apr–May.  +
Arabis pycnocarpa var. adpressipilis +Flowering Mar–Jun.  +
Arabis pycnocarpa var. pycnocarpa +Flowering Mar–Jul.  +
Arbutus arizonica +Flowering May–Jun(-Aug)  +, fruiting Aug–Oct.  +
Arbutus menziesii +Flowering Mar–May(-Jun)  +, fruiting (Jun-)Jul–Sep (-Oct) (fruit sometimes held on the trees into early part of following year).  +
Arbutus xalapensis +Flowering (Feb-)Mar–Apr(-May)  +, ripe fruit appears after about 6 weeks.  +
Arceuthobium americanum +Flowering (Mar–)Apr–Jun  +, fruiting Aug–Sep.  +
Arceuthobium campylopodum subsp. abietinum +Flowering Jul–Aug(–Sep)  +, fruiting Sep–Oct.  +
Arceuthobium campylopodum subsp. apachecum +Flowering Jul–Sep  +, fruiting Aug–Oct.  +
Arceuthobium campylopodum subsp. blumeri +Flowering Jul–Aug  +, fruiting Aug–Oct.  +
Arceuthobium campylopodum subsp. californicum +Flowering Jul–Aug  +, fruiting Sep–Oct.  +
Arceuthobium campylopodum subsp. campylopodum +Flowering Aug–Oct  +, fruiting Sep–Nov.  +
Arceuthobium campylopodum subsp. cyanocarpum +Flowering Jul–Sep  +, fruiting Aug–Sep.  +
Arceuthobium campylopodum subsp. laricis +Flowering Jul–Aug  +, fruiting (Aug–)Sep(–Oct).  +
Arceuthobium campylopodum subsp. littorum +Flowering Aug–Sep  +, fruiting Sep–Oct.  +
Arceuthobium campylopodum subsp. microcarpum +Flowering (Jul–)Aug–Sep  +, fruiting (Aug–)Sep(–Oct).  +
Arceuthobium campylopodum subsp. monticola +Flowering Jul–Aug  +, fruiting Oct–Nov.  +
Arceuthobium campylopodum subsp. occidentale +Flowering Sep–Nov(–Dec)  +, fruiting (Sep–)Oct–Jan(–Feb).  +
Arceuthobium campylopodum subsp. siskiyouense +Flowering Aug–Sep  +, fruiting Sep–Oct.  +
Arceuthobium campylopodum subsp. tsugense +Flowering Jul–Sep(–Oct)  +, fruiting (Aug–)Sep–Nov.  +
Arceuthobium divaricatum +Flowering Aug–Sep  +, fruiting Sep–Oct.  +
Arceuthobium douglasii +Flowering (Mar–)Apr–May(–Jun)  +, fruiting Aug–Sep(–Oct).  +
Arceuthobium gillii +Flowering Feb–Apr  +, fruiting Oct.  +
Arceuthobium pusillum +Flowering (Mar–)Apr–May(–Jun)  +, fruiting Sep–Oct.  +
Arceuthobium vaginatum subsp. cryptopodum +Flowering (Apr–)May–Jun(–Jul)  +, fruiting Jul–Aug(–Sep).  +
Archidium alternifolium +Capsules mature late fall to early spring (Nov–Mar).  +
Archidium donnellii +Capsules mature early spring (Mar), more rarely in autumn or winter (Oct–Dec).  +
Archidium hallii +Capsules mature early spring (Mar) or rarely late fall (Nov).  +
Archidium minus +Capsules mature fall to spring (Sep–Apr).  +
Archidium ohioense +Capsules mature fall through spring (Oct–May).  +
Archidium tenerrimum +Capsules mature late fall to early spring (Oct–Mar).  +
Arctanthemum arcticum subsp. arcticum +Flowering summer.  +
Arctanthemum arcticum subsp. polare +Flowering summer.  +
Arctium lappa +Flowering summer–early fall (Jul–Oct).  +
Arctium minus +Flowering summer–early fall (Jul–Sep).  +
Arctium tomentosum +Flowering summer–early fall (Jul–Oct).  +
Arctoa anderssonii +Capsules mature summer.  +
Arctoa fulvella +Capsules mature summer.  +
Arctoa hyperborea +Capsules mature summer.  +
Arctomecon californica +Flowering mid spring  +, fruiting early summer.  +
Arctomecon humilis +Flowering late spring  +, fruiting mid summer.  +
Arctomecon merriamii +Flowering mid spring  +, fruiting early summer.  +
Arctostaphylos andersonii +Flowering winter–early spring.  +
Arctostaphylos auriculata +Flowering winter–early spring.  +
Arctostaphylos bakeri subsp. bakeri +Flowering winter–early spring.  +
Arctostaphylos bakeri subsp. sublaevis +Flowering winter–early spring.  +
Arctostaphylos canescens subsp. canescens +Flowering early winter–late spring.  +
Arctostaphylos canescens subsp. sonomensis +Flowering early winter–late spring.  +
Arctostaphylos catalinae +Flowering winter–early spring.  +
Arctostaphylos columbiana +Flowering winter–early spring.  +
Arctostaphylos confertiflora +Flowering winter–early spring.  +
Arctostaphylos crustacea subsp. crinita +Flowering winter–early spring.  +
Arctostaphylos crustacea subsp. crustacea +Flowering winter–early spring.  +
Arctostaphylos crustacea subsp. eastwoodiana +Flowering winter–early spring.  +
Arctostaphylos crustacea subsp. insulicola +Flowering winter–early spring.  +
Arctostaphylos crustacea subsp. rosei +Flowering winter–early spring.  +
Arctostaphylos crustacea subsp. subcordata +Flowering winter–early spring.  +
Arctostaphylos cruzensis +Flowering winter–early spring.  +
Arctostaphylos densiflora +Flowering winter–early spring.  +
Arctostaphylos edmundsii +Flowering winter–early spring.  +
Arctostaphylos franciscana +Flowering winter–early spring.  +
Arctostaphylos gabilanensis +Flowering winter–early spring.  +
Arctostaphylos glandulosa subsp. adamsii +Flowering winter–early spring.  +
Arctostaphylos glandulosa subsp. crassifolia +Flowering winter–early spring.  +
Arctostaphylos glandulosa subsp. cushingiana +Flowering winter–early spring.  +
Arctostaphylos glandulosa subsp. gabrielensis +Flowering winter–early spring.  +
Arctostaphylos glandulosa subsp. glandulosa +Flowering winter–early spring.  +
Arctostaphylos glandulosa subsp. howellii +Flowering winter–early spring.  +
Arctostaphylos glandulosa subsp. leucophylla +Flowering winter–early spring.  +
Arctostaphylos glandulosa subsp. mollis +Flowering winter–early spring.  +
Arctostaphylos glauca +Flowering winter–early spring.  +
Arctostaphylos glutinosa +Flowering winter–early spring.  +
Arctostaphylos hispidula +Flowering winter–early spring.  +
Arctostaphylos hookeri subsp. hearstiorum +Flowering winter–early spring.  +
Arctostaphylos hookeri subsp. hookeri +Flowering winter–early spring.  +
Arctostaphylos hooveri +Flowering winter–early spring.  +
Arctostaphylos imbricata +Flowering winter–early spring.  +
Arctostaphylos insularis +Flowering winter–early spring.  +
Arctostaphylos klamathensis +Flowering late spring.  +
Arctostaphylos luciana +Flowering winter–early spring.  +
Arctostaphylos malloryi +Flowering winter–late spring.  +
Arctostaphylos manzanita subsp. elegans +Flowering winter–early spring.  +
Arctostaphylos manzanita subsp. glaucescens +Flowering winter–early spring.  +
Arctostaphylos manzanita subsp. laevigata +Flowering winter–early spring.  +
Arctostaphylos manzanita subsp. manzanita +Flowering winter–early spring.  +
Arctostaphylos manzanita subsp. roofii +Flowering winter–early spring.  +
Arctostaphylos manzanita subsp. wieslanderi +Flowering early–late spring.  +
Arctostaphylos mewukka subsp. mewukka +Flowering late spring–early summer.  +
Arctostaphylos mewukka subsp. truei +Flowering late spring–early summer.  +
Arctostaphylos montana subsp. montana +Flowering late spring.  +
Arctostaphylos montana subsp. ravenii +Flowering early–late spring.  +
Arctostaphylos montaraensis +Flowering winter–early spring.  +
Arctostaphylos montereyensis +Flowering winter–early spring.  +
Arctostaphylos morroensis +Flowering winter–early spring.  +
Arctostaphylos myrtifolia +Flowering winter–early spring.  +
Arctostaphylos nevadensis subsp. knightii +Flowering late spring.  +
Arctostaphylos nevadensis subsp. nevadensis +Flowering late spring.  +
Arctostaphylos nissenana +Flowering winter–early spring.  +
Arctostaphylos nortensis +Flowering late winter–late spring.  +
Arctostaphylos nummularia subsp. mendocinoensis +Flowering winter–early spring.  +
Arctostaphylos nummularia subsp. nummularia +Flowering winter–early spring.  +
Arctostaphylos obispoensis +Flowering winter–early spring.  +
Arctostaphylos ohloneana +Flowering winter–early spring.  +
Arctostaphylos osoensis +Flowering winter–early spring.  +
Arctostaphylos otayensis +Flowering winter–early spring.  +
Arctostaphylos pacifica +Flowering winter–early spring.  +
Arctostaphylos pajaroensis +Flowering early winter–early spring.  +
Arctostaphylos pallida +Flowering winter–early spring.  +
Arctostaphylos parryana subsp. desertica +Flowering winter–early spring.  +
Arctostaphylos parryana subsp. parryana +Flowering late spring–early summer.  +
Arctostaphylos parryana subsp. tumescens +Flowering early–late spring.  +
Arctostaphylos patula +Flowering late spring–early summer.  +
Arctostaphylos pechoensis +Flowering winter–early spring.  +
Arctostaphylos pilosula +Flowering winter–early spring.  +
Arctostaphylos pringlei subsp. drupacea +Flowering early–late spring.  +
Arctostaphylos pringlei subsp. pringlei +Flowering early–late spring.  +
Arctostaphylos pumila +Flowering winter–early spring.  +
Arctostaphylos pungens +Flowering winter–early summer.  +
Arctostaphylos purissima +Flowering winter–early spring.  +
Arctostaphylos rainbowensis +Flowering winter–early spring.  +
Arctostaphylos refugioensis +Flowering winter–early spring.  +
Arctostaphylos regismontana +Flowering winter–early spring.  +
Arctostaphylos rudis +Flowering winter–early spring.  +
Arctostaphylos sensitiva +Flowering winter–early spring.  +
Arctostaphylos silvicola +Flowering winter–early spring.  +
Arctostaphylos stanfordiana subsp. decumbens +Flowering winter–early spring.  +
Arctostaphylos stanfordiana subsp. raichei +Flowering winter–early spring.  +
Arctostaphylos stanfordiana subsp. stanfordiana +Flowering winter–early spring.  +
Arctostaphylos tomentosa subsp. bracteosa +Flowering winter–early spring.  +
Arctostaphylos tomentosa subsp. daciticola +Flowering winter–early spring.  +
Arctostaphylos tomentosa subsp. hebeclada +Flowering winter–early spring.  +
Arctostaphylos tomentosa subsp. tomentosa +Flowering winter–early spring.  +
Arctostaphylos uva-ursi +Flowering winter–early summer.  +
Arctostaphylos virgata +Flowering early winter–early spring.  +
Arctostaphylos viridissima +Flowering winter–early spring.  +
Arctostaphylos viscida subsp. mariposa +Flowering winter–early spring.  +
Arctostaphylos viscida subsp. pulchella +Flowering winter–early spring.  +
Arctostaphylos viscida subsp. viscida +Flowering winter–early spring.  +
Arctotheca calendula +Flowering Oct–Aug.  +
Arctotis fastuosa +Flowering spring–summer.  +
Arctotis stoechadifolia +Flowering (Jan–)Apr–Nov.  +
Arctous alpina +Flowering early summer.  +
Arctous rubra +Flowering summer.  +
Ardisia crenata +Flowering May–Jun  +, fruiting Jul–Dec.  +
Ardisia elliptica +Flowering Feb–Apr  +, fruiting Sep–Nov.  +
Ardisia escallonioides +Flowering May–Jun  +, fruiting Nov–May.  +
Ardisia japonica +Flowering Apr–Jun  +, fruiting Nov–Jan.  +
Arenaria benthamii +Flowering late spring.  +
Arenaria humifusa +Flowering spring–summer.  +
Arenaria lanuginosa var. lanuginosa +Flowering spring–summer.  +
Arenaria lanuginosa var. saxosa +Flowering spring–summer.  +
Arenaria livermorensis +Flowering spring–summer.  +
Arenaria longipedunculata +Flowering spring–summer.  +
Arenaria ludens +Flowering late summer–early autumn.  +
Arenaria paludicola +Flowering late spring–summer.  +
Arenaria pseudofrigida +Flowering spring–summer.  +
Arenaria serpyllifolia var. serpyllifolia +Flowering spring–summer.  +
Arenaria serpyllifolia var. tenuior +Flowering spring–summer.  +
Arethusa bulbosa +Flowering Jun–Jul.  +
Argemone aenea +Flowering and fruiting early spring–summer.  +
Argemone albiflora subsp. albiflora +Flowering early spring–summer  +, fruiting late spring–summer.  +
Argemone albiflora subsp. texana +Flowering early spring–summer  +, fruiting spring–fall.  +
Argemone arizonica +Flowering spring  +, fruiting summer.  +
Argemone aurantiaca +Flowering spring–summer  +, fruiting summer–fall.  +
Argemone chisosensis +Flowering and fruiting spring–fall.  +
Argemone corymbosa subsp. arenicola +Flowering spring  +, fruiting spring–summer.  +
Argemone corymbosa subsp. corymbosa +Flowering and fruiting spring.  +
Argemone gracilenta +Flowering spring  +, fruiting spring–summer.  +
Argemone hispida +Flowering spring–summer  +, fruiting summer–fall.  +
Argemone mexicana +Flowering and fruiting spring–fall, or throughout year in tropics.  +
Argemone munita subsp. argentea +Flowering spring  +, fruiting spring–summer.  +
Argemone munita subsp. munita +Flowering spring–summer  +, fruiting summer–fall.  +
Argemone munita subsp. robusta +Flowering spring–summer  +, fruiting summer–fall.  +
Argemone munita subsp. rotundata +Flowering spring–fall  +, fruiting summer–fall.  +
Argemone ochroleuca +Flowering and fruiting spring–fall.  +
Argemone pleiacantha subsp. ambigua +Flowering spring–summer  +, fruiting summer–fall.  +
Argemone pleiacantha subsp. pinnatisecta +Flowering spring–summer  +, fruiting summer–fall.  +
Argemone pleiacantha subsp. pleiacantha +Flowering spring–summer  +, fruiting summer–fall.  +
Argemone polyanthemos +Flowering spring–summer  +, fruiting late spring–summer.  +
Argemone sanguinea +Flowering early spring–summer  +, fruiting spring–summer.  +
Argemone squarrosa subsp. glabrata +Flowering spring–summer  +, fruiting summer–fall.  +
Argemone squarrosa subsp. squarrosa +Flowering spring–summer  +, fruiting summer–fall.  +
Argyranthemum foeniculaceum +Flowering May.  +
Argyrochosma dealbata +Sporulating summer–fall.  +
Argyrochosma fendleri +Sporulating summer–fall.  +
Argyrochosma incana +Sporulating summer–fall.  +
Argyrochosma jonesii +Sporulating spring–fall.  +
Argyrochosma limitanea subsp. limitanea +Sporulating summer–fall.  +
Argyrochosma limitanea subsp. mexicana +Sporulating summer–fall.  +
Argyrochosma microphylla +Sporulating summer–fall.  +
Argythamnia adenophora +Flowering Jan–Mar and Jul–Oct.  +
Argythamnia aphoroides +Flowering Jan–Jul.  +
Argythamnia argothamnoides +Flowering year-round.  +
Argythamnia argyraea +Flowering Apr–Jul.  +
Argythamnia brandegeei var. intonsa +Flowering year-round.  +
Argythamnia claryana +Flowering Feb–Apr and Oct–Nov.  +
Argythamnia cyanophylla +Flowering Mar–Jun and Aug–Oct.  +
Argythamnia humilis +Flowering year-round.  +
Argythamnia lanceolata +Flowering year-round.  +
Argythamnia mercurialina var. mercurialina +Flowering Mar–Aug.  +
Argythamnia mercurialina var. pilosissima +Flowering from Mar–Jul.  +
Argythamnia serrata +Flowering year-round.  +
Argythamnia simulans +Flowering Mar–Nov.  +
Arida arizonica +Flowering Mar–Nov.  +
Arida blepharophylla +Flowering Sep–Oct.  +
Arida carnosa +Flowering Aug–Sep.  +
Arida mattturneri +Flowering Apr–Jul.  +
Arida parviflora +Flowering Jul–Oct.  +
Arida riparia +Flowering Apr–Sep.  +
Ariocarpus fissuratus var. fissuratus +Flowering Sep–Nov.  +
Arisaema dracontium +Flowering late winter (southern part of range)–late spring.  +
Arisaema triphyllum +Flowering early–late spring.  +
Aristocapsa insignis +Flowering May–Jun.  +
Aristolochia californica +Flowering spring.  +
Aristolochia clematitis +Flowering summer.  +
Aristolochia coryi +Flowering late spring–summer.  +
Aristolochia erecta +Flowering late spring–summer.  +
Aristolochia macrophylla +Flowering late spring–summer.  +
Aristolochia maxima +Flowering all year.  +
Aristolochia pentandra +Flowering winter–early spring.  +
Aristolochia reticulata +Flowering late spring–summer.  +
Aristolochia serpentaria +Flowering late spring–summer.  +
Aristolochia tomentosa +Flowering late spring–summer.  +
Aristolochia watsonii +Flowering spring–summer.  +
Aristolochia wrightii +Flowering all year.  +
Arivela viscosa +Flowering summer.  +
Armeria maritima subsp. californica +Flowering mid spring-mid summer.  +
Armeria maritima subsp. interior +Flowering summer.  +
Armeria maritima subsp. maritima +Flowering late spring–early summer.  +
Armeria maritima subsp. sibirica +Flowering summer.  +
Armoracia rusticana +Flowering Mar–Jul.  +
Arnica acaulis +Flowering Apr–Jun.  +
Arnica angustifolia subsp. angustifolia +Flowering May–Sep.  +
Arnica angustifolia subsp. tomentosa +Flowering Jul–Aug.  +
Arnica cernua +Flowering Apr–Jun.  +
Arnica chamissonis +Flowering Apr–Sep.  +
Arnica cordifolia +Flowering May–Jul.  +
Arnica dealbata +Flowering Jun–Aug.  +
Arnica discoidea +Flowering May–Jul.  +
Arnica fulgens +Flowering May–Jul.  +
Arnica gracilis +Flowering Jul–Aug.  +
Arnica griscomii subsp. frigida +Flowering Jul–Aug.  +
Arnica griscomii subsp. griscomii +Flowering Jun–Jul.  +
Arnica lanceolata subsp. lanceolata +Flowering Jun–Sep.  +
Arnica lanceolata subsp. prima +Flowering May–Sep.  +
Arnica latifolia +Flowering Jul–Aug.  +
Arnica lessingii +Flowering Jun–Sep.  +
Arnica lonchophylla +Flowering June–Aug.  +
Arnica longifolia +Flowering Jun–Oct.  +
Arnica louiseana +Flowering Jul–Aug.  +
Arnica mollis +Flowering Jun–Sep.  +
Arnica nevadensis +Flowering Jul–Aug.  +
Arnica ovata +Flowering Jul–Sep.  +
Arnica parryi +Flowering May–Sep.  +
Arnica rydbergii +Flowering Jul–Aug.  +
Arnica sororia +Flowering May–Jul.  +
Arnica spathulata +Flowering Apr–Jul.  +
Arnica unalaschcensis +Flowering Jun–Aug.  +
Arnica venosa +Flowering May–Jun.  +
Arnica viscosa +Flowering Aug–Sep.  +
Arnoglossum album +Flowering May–mid July.  +
Arnoglossum atriplicifolium +Flowering Jul–Nov.  +
Arnoglossum diversifolium +Flowering mid May–early Jul (Aug–Sep, peninsular Florida).  +
Arnoglossum floridanum +Flowering May–Jul.  +
Arnoglossum ovatum +Flowering (May–)Aug–Oct(–Dec).  +
Arnoglossum plantagineum +Flowering May (south)–Aug (north).  +
Arnoglossum reniforme +Flowering mid May–early Sep.  +
Arnoglossum sulcatum +Flowering Sep–Nov.  +
Arnoseris minima +Flowering Jun–Sep.  +
Aronia arbutifolia +Flowering Feb–May  +, fruiting Sep–Nov.  +
Aronia melanocarpa +Flowering Mar–Jun  +, fruiting Sep–Nov.  +
Artemisia abrotanum +Flowering late summer–fall.  +
Artemisia absinthium +Flowering mid summer–fall.  +
Artemisia alaskana +Flowering early–late summer.  +
Artemisia aleutica +Flowering mid–late summer.  +
Artemisia annua +Flowering late summer–fall.  +
Artemisia arbuscula subsp. arbuscula +Flowering mid–late summer.  +
Artemisia arbuscula subsp. longiloba +Flowering early–late spring.  +
Artemisia arbuscula subsp. thermopola +Flowering mid–late summer.  +
Artemisia biennis +Flowering mid summer–late fall.  +
Artemisia bigelovii +Flowering early summer–late fall.  +
Artemisia borealis subsp. borealis +Flowering mid–late summer.  +
Artemisia borealis subsp. richardsoniana +Flowering mid–late summer.  +
Artemisia californica +Flowering early–late summer.  +
Artemisia campestris subsp. canadensis +Flowering early–late summer.  +
Artemisia campestris subsp. caudata +Flowering early–late summer.  +
Artemisia campestris subsp. pacifica +Flowering mid–late summer.  +
Artemisia cana subsp. bolanderi +Flowering mid–late summer.  +
Artemisia cana subsp. cana +Flowering mid–late summer.  +
Artemisia cana subsp. viscidula +Flowering mid–late summer.  +
Artemisia carruthii +Flowering mid summer–early fall.  +
Artemisia douglasiana +Flowering mid spring–late fall.  +
Artemisia dracunculus +Flowering mid summer–late fall.  +
Artemisia filifolia +Flowering late summer–early winter.  +
Artemisia franserioides +Flowering late summer–early fall.  +
Artemisia frigida +Flowering summer–fall.  +
Artemisia furcata +Flowering late summer.  +
Artemisia globularia subsp. globularia +Flowering late summer.  +
Artemisia globularia subsp. lutea +Flowering late spring–mid summer.  +
Artemisia glomerata +Flowering mid summer.  +
Artemisia laciniata subsp. laciniata +Flowering mid–late summer.  +
Artemisia laciniata subsp. parryi +Flowering late summer–fall.  +
Artemisia longifolia +Flowering mid summer–early fall.  +
Artemisia ludoviciana subsp. albula +Flowering early summer–fall.  +
Artemisia ludoviciana subsp. candicans +Flowering mid–late summer.  +
Artemisia ludoviciana subsp. incompta +Flowering mid summer–late fall.  +
Artemisia ludoviciana subsp. ludoviciana +Flowering mid summer–late fall.  +
Artemisia ludoviciana subsp. mexicana +Flowering late summer–late fall.  +
Artemisia ludoviciana subsp. redolens +Flowering mid–late summer.  +
Artemisia michauxiana +Flowering mid summer–early fall.  +
Artemisia nesiotica +Flowering mid–late summer.  +
Artemisia norvegica subsp. saxatilis +Flowering mid–late summer.  +
Artemisia nova +Flowering mid summer–late fall.  +
Artemisia packardiae +Flowering late summer.  +
Artemisia palmeri +Flowering early–mid summer.  +
Artemisia papposa +Flowering early spring–mid summer.  +
Artemisia pattersonii +Flowering mid–late summer.  +
Artemisia pedatifida +Flowering early spring–mid summer.  +
Artemisia pontica +Flowering late summer–fall.  +
Artemisia porteri +Flowering mid–late summer.  +
Artemisia pycnocephala +Flowering late spring–mid summer.  +
Artemisia pygmaea +Flowering mid summer–fall.  +
Artemisia rigida +Flowering mid summer–early fall.  +
Artemisia rothrockii +Flowering mid summer–all.  +
Artemisia rupestris +Flowering late summer–fall.  +
Artemisia scopulorum +Flowering mid–late summer.  +
Artemisia senjavinensis +Flowering mid–late summer.  +
Artemisia serrata +Flowering mid summer–early fall.  +
Artemisia spiciformis +Flowering mid summer–fall.  +
Artemisia stelleriana +Flowering early spring–fall.  +
Artemisia suksdorfii +Flowering mid summer–fall.  +
Artemisia tilesii +Flowering mid summer–early fall.  +
Artemisia tridentata subsp. parishii +Flowering mid summer–late fall.  +
Artemisia tridentata subsp. tridentata +Flowering mid summer–late fall.  +
Artemisia tridentata subsp. vaseyana +Flowering mid summer–late fall.  +
Artemisia tridentata subsp. wyomingensis +Flowering mid summer–late fall.  +
Artemisia tripartita subsp. rupicola +Flowering early–late summer.  +
Artemisia tripartita subsp. tripartita +Flowering mid summer–late fall.  +
Artemisia vulgaris +Flowering mid summer–late fall.  +
Arthrocnemum subterminale +Flowering late spring–late summer.  +
Aruncus dioicus var. acuminatus +Flowering early summer.  +
Aruncus dioicus var. dioicus +Flowering early summer.  +
Aruncus dioicus var. pubescens +Flowering early summer.  +
Aruncus dioicus var. vulgaris +Flowering summer.  +
Asanthus squamulosus +Flowering Apr–May.  +
Asarum canadense +Flowering spring–early summer (Mar–Jul).  +
Asarum caudatum +Flowering spring–summer (Apr–Jul).  +
Asarum hartwegii +Flowering spring–summer (Apr–Jul).  +
Asarum lemmonii +Flowering spring–summer (May–Jul).  +
Asarum marmoratum +Flowering late winter–spring (Mar–Jun).  +
Asarum wagneri +Flowering spring–summer (May–Jul).  +
Aschisma kansanum +Capsules mature Apr.  +
Asimina incana +Flowering spring–early summer.  +
Asimina longifolia var. longifolia +Flowering spring–early summer, all year if disturbed.  +
Asimina longifolia var. spatulata +Flowering spring–early summer(-fall).  +
Asimina obovata +Flowering late winter–early summer.  +
Asimina parviflora +Flowering early spring.  +
Asimina pygmaea +Flowering spring–early summer.  +
Asimina reticulata +Flowering winter–spring.  +
Asimina tetramera +Flowering spring–summer, all year if disturbed.  +
Asimina triloba +Flowering early spring.  +
Asparagus aethiopicus +Flowering spring–summer.  +
Asparagus asparagoides +Flowering spring–summer.  +
Asparagus officinalis +Flowering summer.  +
Asparagus setaceus +Flowering spring–summer.  +
Asphodelus fistulosus +Flowering late winter–spring.  +
Aspicarpa hirtella +Flowering and fruiting (May–)Jul–Sep(–Oct).  +
Aspicarpa hyssopifolia +Flowering and fruiting Apr–Nov.  +
Aster alpinus subsp. vierhapperi +Flowering early summer.  +
Aster tataricus +Flowering fall.  +
Astilbe biternata +Flowering Jun.  +
Astraea lobata +Flowering Jun–Nov.  +
Astranthium ciliatum +Flowering Mar–May.  +
Astranthium integrifolium +Flowering Apr–Jun(–Jul).  +
Astranthium robustum +Flowering Mar–Jun.  +
Astrolepis cochisensis subsp. arizonica +Sporulating summer–fall.  +
Astrolepis cochisensis subsp. chihuahuensis +Sporulating summer–fall.  +
Astrolepis cochisensis subsp. cochisensis +Sporulating summer–fall.  +
Astrolepis integerrima +Sporulating summer–fall.  +
Astrolepis sinuata subsp. mexicana +Sporulating summer–fall.  +
Astrolepis sinuata subsp. sinuata +Sporulating summer–fall.  +
Astrolepis windhamii +Sporulating summer–fall.  +
Astrophytum asterias +Flowering Mar–May and sporadically after summer rainfall.  +
Atamisquea emarginata +Flowering early summer.  +
Athysanus pusillus +Flowering Feb–Jun.  +
Athysanus unilateralis +Flowering Feb–May.  +
Atrichoseris platyphylla +Flowering Feb–May.  +
Atrichum altecristatum +Capsules mature spring–fall (Mar–Oct).  +
Atrichum angustatum +Capsules mature spring–summer (Apr–Jul).  +
Atrichum crispulum +Capsules mature summer (Jun–Aug).  +
Atrichum crispum +Capsules mature spring–summer (Apr–June).  +
Atrichum flavisetum +Capsule maturity date not determined.  +
Atrichum selwynii +Capsules mature spring–late summer (Mar–Sept).  +
Atrichum tenellum +Capsules mature late summer (Aug–Sep).  +
Atrichum undulatum +Capsules mature spring–summer (Apr- Jul).  +
Atriplex amnicola +Flowering summer–fall.  +
Atriplex argentea var. argentea +Flowering summer–fall.  +
Atriplex argentea var. hillmanii +Flowering summer–fall.  +
Atriplex argentea var. longitrichoma +Flowering summer–fall.  +
Atriplex argentea var. mohavensis +Flowering summer–fall.  +
Atriplex argentea var. rydbergii +Flowering summer–fall.  +
Atriplex californica +Flowering Apr–Nov.  +
Atriplex canescens var. canescens +Flowering spring–fall.  +
Atriplex canescens var. gigantea +Flowering summer–fall.  +
Atriplex canescens var. laciniata +Flowering spring–fall.  +
Atriplex canescens var. macilenta +Flowering spring–fall.  +
Atriplex confertifolia +Flowering spring–fall.  +
Atriplex cordulata var. cordulata +Flowering spring–fall.  +
Atriplex cordulata var. erecticaulis +Flowering summer–early fall.  +
Atriplex coronata var. coronata +Flowering spring–fall.  +
Atriplex coronata var. notatior +Flowering spring–fall.  +
Atriplex coronata var. vallicola +Flowering spring–fall.  +
Atriplex corrugata +Flowering spring–fall.  +
Atriplex coulteri +Flowering spring–fall.  +
Atriplex covillei +Flowering summer–fall.  +
Atriplex dioica +Flowering summer–fall.  +
Atriplex elegans var. elegans +Flowering spring–fall.  +
Atriplex elegans var. fasciculata +Flowering spring–fall.  +
Atriplex fruticulosa +Flowering summer–fall.  +
Atriplex gardneri var. aptera +Flowering summer–fall.  +
Atriplex gardneri var. bonnevillensis +Flowering summer–fall.  +
Atriplex gardneri var. cuneata +Flowering spring–fall.  +
Atriplex gardneri var. falcata +Flowering summer–fall.  +
Atriplex gardneri var. gardneri +Flowering spring–fall.  +
Atriplex gardneri var. utahensis +Flowering summer–fall.  +
Atriplex gardneri var. welshii +Flowering spring–fall.  +
Atriplex garrettii var. garrettii +Flowering spring–fall.  +
Atriplex garrettii var. navajoensis +Flowering summer–fall.  +
Atriplex glabriuscula var. acadiensis +Flowering late summer–fall.  +
Atriplex glabriuscula var. franktonii +Flowering late summer–fall.  +
Atriplex glabriuscula var. glabriuscula +Flowering late summer.  +
Atriplex gmelinii var. alaskensis +Flowering summer.  +
Atriplex gmelinii var. gmelinii +Flowering summer.  +
Atriplex graciliflora +Flowering summer.  +
Atriplex heterosperma +Flowering summer–fall.  +
Atriplex holocarpa +Flowering summer.  +
Atriplex hortensis +Flowering summer–fall.  +
Atriplex hymenelytra +Flowering spring.  +
Atriplex joaquiniana +Flowering summer.  +
Atriplex klebergorum +Flowering summer.  +
Atriplex laciniata +Flowering summer–fall.  +
Atriplex lentiformis +Flowering spring–fall.  +
Atriplex leucophylla +Flowering spring–fall.  +
Atriplex linearis +Flowering spring–fall.  +
Atriplex littoralis +Flowering summer.  +
Atriplex matamorensis +Flowering summer and fall.  +
Atriplex mucronata +Flowering summer–fall.  +
Atriplex nudicaulis +Flowering late summer–fall.  +
Atriplex nummularia +Flowering summer–fall.  +
Atriplex oblongifolia +Flowering summer.  +
Atriplex obovata +Flowering summer–fall.  +
Atriplex pacifica +Flowering early spring–fall.  +
Atriplex parishii var. depressa +Flowering late summer–fall.  +
Atriplex parishii var. minuscula +Flowering late summer–fall.  +
Atriplex parishii var. parishii +Flowering late summer–fall.  +
Atriplex parishii var. persistens +Flowering spring–fall.  +
Atriplex parishii var. subtilis +Flowering late spring–fall.  +
Atriplex parryi +Flowering spring–fall.  +
Atriplex patula +Flowering summer–fall.  +
Atriplex pentandra +Flowering summer–fall.  +
Atriplex phyllostegia +Flowering Apr–Aug.  +
Atriplex pleiantha +Flowering late summer–fall.  +
Atriplex polycarpa +Flowering spring–fall.  +
Atriplex powellii var. minuticarpa +Flowering spring–fall.  +
Atriplex powellii var. powellii +Flowering summer–fall.  +
Atriplex prostrata +Flowering in summer–fall.  +
Atriplex pusilla +Flowering Jun–Oct.  +
Atriplex rosea +Flowering mid summer–fall.  +
Atriplex saccaria var. asterocarpa +Flowering Apr–Sep.  +
Atriplex saccaria var. cornuta +Flowering late summer–fall.  +
Atriplex semibaccata +Flowering spring–early winter.  +
Atriplex serenana var. davidsonii +Flowering spring–fall.  +
Atriplex serenana var. serenana +Flowering spring–fall.  +
Atriplex spinifera +Flowering summer–fall.  +
Atriplex suberecta +Flowering summer–fall.  +
Atriplex suckleyi +Flowering late summer–fall.  +
Atriplex tatarica +Flowering late summer–fall.  +
Atriplex torreyi var. griffithsii +Flowering spring–winter.  +
Atriplex torreyi var. torreyi +Flowering spring–fall.  +
Atriplex truncata +Flowering summer–fall.  +
Atriplex tularensis +Flowering summer–fall.  +
Atriplex watsonii +Flowering spring–fall.  +
Atriplex wolfii var. tenuissima +Flowering summer–fall.  +
Atriplex wolfii var. wolfii +Flowering summer–fall.  +
Atriplex wrightii +Flowering summer–fall.  +
Aubrieta deltoidea +Flowering Apr–Jun.  +
Aucuba japonica +Flowering Mar–Apr.  +
Aureolaria flava +Flowering Jul–Oct.  +
Aureolaria grandiflora +Flowering Jul–Oct.  +
Aureolaria levigata +Flowering Jul–Oct.  +
Aureolaria patula +Flowering Aug–Oct.  +
Aureolaria pectinata +Flowering Jun–Sep.  +
Aureolaria pedicularia +Flowering Jun–Sep.  +
Aureolaria virginica +Flowering Jun–Sep.  +
Aurinia petraea +Flowering May–Jul.  +
Aurinia saxatilis +Flowering May–Jul.  +
Axyris amaranthoides +Flowering summer–fall.  +
Ayenia compacta +Flowering and fruiting spring–early fall.  +
Ayenia euphrasiifolia +Flowering and fruiting year-round.  +
Ayenia filiformis +Flowering and fruiting spring–early fall.  +
Ayenia jaliscana +Flowering and fruiting late summer–early winter.  +
Ayenia limitaris +Flowering summer  +, fruiting summer–fall.  +
Ayenia microphylla +Flowering and fruiting spring–early fall.  +
Ayenia pilosa +Flowering and fruiting year-round.  +
Baccharis angustifolia +Flowering Sep–Nov.  +
Baccharis bigelovii +Flowering Aug–Nov.  +
Baccharis brachyphylla +Flowering Jul–Aug.  +
Baccharis dioica +Flowering Aug–Nov.  +
Baccharis douglasii +Flowering Jul–Oct (all year).  +
Baccharis glomeruliflora +Flowering Oct–Nov.  +
Baccharis halimifolia +Flowering Aug–Nov.  +
Baccharis havardii +Flowering Jul–Sep.  +
Baccharis malibuensis +Flowering Aug–Sep.  +
Baccharis neglecta +Flowering Aug–Nov.  +
Baccharis pilularis subsp. consanguinea +Flowering Jul–Dec.  +
Baccharis pilularis subsp. pilularis +Flowering Jul–Dec.  +
Baccharis plummerae subsp. glabrata +Flowering Jun–Nov.  +
Baccharis plummerae subsp. plummerae +Flowering (May–)Aug–Nov.  +
Baccharis pteronioides +Flowering Apr–Jun.  +
Baccharis salicifolia +Flowering (Jan–)Mar–Oct.  +
Baccharis salicina +Flowering May–Nov.  +
Baccharis sarothroides +Flowering Aug–Nov.  +
Baccharis sergiloides +Flowering Jul–Oct.  +
Baccharis texana +Flowering Aug–Nov.  +
Baccharis thesioides +Flowering Aug–Nov.  +
Baccharis vanessae +Flowering Oct.  +
Baccharis wrightii +Flowering Apr–Jul.  +
Bacopa caroliniana +Flowering Jun–Nov.  +
Bacopa egensis +Flowering Aug–Oct.  +
Bacopa eisenii +Flowering May–Oct.  +
Bacopa innominata +Flowering Jun–Sep.  +
Bacopa monnieri +Flowering Apr–Sep.  +
Bacopa repens +Flowering Jul–Sep.  +
Bacopa rotundifolia +Flowering May–Nov.  +
Bahia absinthifolia +Flowering Mar–Nov.  +
Bahia bigelovii +Flowering Jun–Oct.  +
Bahia biternata +Flowering (May–)Sep–Oct.  +
Bahia pedata +Flowering (May–)Jul–Aug(–Nov).  +
Bahiopsis laciniata +Flowering Jan–Jun(–Sep).  +
Bahiopsis parishii +Flowering (Jan–Oct).  +
Bahiopsis reticulata +Flowering Mar–Jun.  +
Baileya multiradiata +Flowering Mar–Nov (depending on rains).  +
Baileya pauciradiata +Flowering Mar–May.  +
Baileya pleniradiata +Flowering Mar–Nov (depending on rains).  +
Balduina angustifolia +Flowering summer–fall (year round south).  +
Balduina atropurpurea +Flowering summer–fall.  +
Balduina uniflora +Flowering summer–fall.  +
Balsamorhiza careyana +Flowering (Mar–)May–Jun(–Jul).  +
Balsamorhiza deltoidea +Flowering (Mar–)Apr–Jun(–Jul).  +
Balsamorhiza hispidula +Flowering Apr–May.  +
Balsamorhiza hookeri +Flowering Apr–May(–Jul).  +
Balsamorhiza incana +Flowering May–Jun(–Jul).  +
Balsamorhiza lanata +Flowering Apr–May(–Jun).  +
Balsamorhiza macrolepis +Flowering Apr–Jun.  +
Balsamorhiza macrophylla +Flowering May–Jul.  +
Balsamorhiza rosea +Flowering Apr–May.  +
Balsamorhiza sagittata +Flowering (Apr–)May–Jun(–Jul).  +
Balsamorhiza sericea +Flowering Apr–May.  +
Balsamorhiza serrata +Flowering Apr–Jun.  +
Barbarea orthoceras +Flowering Mar–Jul.  +
Barbarea stricta +Flowering Apr–Jul.  +
Barbarea verna +Flowering Mar–Jul.  +
Barbarea vulgaris +Flowering Apr–Jul.  +
Barbella pendula +Capsules mature Mar.  +
Barbula convoluta var. convoluta +Capsules mature spring–summer (Mar–Aug, Jun).  +
Barbula convoluta var. eustegia +Capsules mature late spring, summer–fall (May, Jun, Jul, Oct).  +
Barbula unguiculata +Capsules mature in winter and early spring, occasionally summer or fall.  +
Barkleyanthus salicifolius +Flowering year-round, mostly spring.  +
Bartlettia scaposa +Flowering summer–fall, following rains.  +
Bartramia brevifolia +Capsules mature Nov.  +
Bartramia halleriana +Spores 15-24 µm, mature Jun–Sep.  +
Bartramia ithyphylla +Capsules mature Jul–Nov.  +
Bartramia pomiformis +Capsules mature Feb–Nov.  +
Bartramia stricta +Capsules mature Jan–Aug.  +
Bartramia subulata +Capsules mature Aug–Nov.  +
Bartsia alpina +Flowering Jun–Aug.  +
Basiphyllaea corallicola +Flowering Sep–Nov.  +
Bassia hirsuta +Flowering late summer–fall.  +
Bassia hyssopifolia +Flowering late summer–fall.  +
Bastardia viscosa +Flowering year-round.  +
Batesimalva violacea +Flowering fall.  +
Batis maritima +Flowering (Jan-)Apr–Sep [year-round in the tropics].  +
Bebbia juncea var. aspera +Flowering mostly year round.  +
Begonia cucullata +Flowering spring.  +
Begonia hirtella +Flowering spring.  +
Bejaria racemosa +Flowering spring.  +
Belamcanda chinensis +Flowering Jun–Aug.  +
Bellardia latifolia +Flowering Apr–May.  +
Bellardia trixago +Flowering Mar–Jun.  +
Bellardia viscosa +Flowering Apr–Sep.  +
Bellis perennis +Flowering spring–summer.  +
Beloglottis costaricensis +Flowering Mar–Apr.  +
Benitoa occidentalis +Flowering Jun–Nov.  +
Bensoniella oregona +Flowering May–Aug.  +
Berberis amplectens +Flowering spring (Apr–May).  +
Berberis aquifolium +Flowering winter–spring (Mar–Jun).  +
Berberis bealei +Flowering fall–winter (Dec–Mar).  +
Berberis canadensis +Flowering spring (Apr–May).  +
Berberis darwinii +Flowering winter (Feb).  +
Berberis dictyota +Flowering winter–spring (Mar–Apr).  +
Berberis fendleri +Flowering spring–summer (May–Aug).  +
Berberis fremontii +Flowering spring (Apr–Jun).  +
Berberis haematocarpa +Flowering winter–spring (Feb–Jun).  +
Berberis harrisoniana +Flowering winter (Jan–Mar).  +
Berberis higginsiae +Flowering spring (Apr–Jun).  +
Berberis nervosa +Flowering winter–spring (Mar–Jun).  +
Berberis nevinii +Flowering winter–spring (Feb–May).  +
Berberis pinnata subsp. insularis +Flowering winter (Mar).  +
Berberis pinnata subsp. pinnata +Flowering winter–spring (Feb–May).  +
Berberis piperiana +Flowering winter–spring (Mar–Jun).  +
Berberis pumila +Flowering winter–spring (Mar–May).  +
Berberis repens +Flowering spring (Apr–Jun).  +
Berberis swaseyi +Flowering winter–spring (Feb–Apr).  +
Berberis thunbergii +Flowering late winter–spring (Mar–May).  +
Berberis trifoliolata +Flowering winter–spring (Feb–Apr).  +
Berberis vulgaris +Flowering spring (May–Jun).  +
Berberis wilcoxii +Flowering spring (Apr–May).  +
Berchemia scandens +Flowering Mar–May.  +
Bergerocactus emoryi +Flowering Apr–Jul.  +
Bergia texana +Flowering summer(–early fall).  +
Berlandiera lyrata +Flowering nearly year round.  +
Berlandiera monocephala +Flowering May–Oct.  +
Berlandiera pumila +Flowering Apr–Aug.  +
Berlandiera subacaulis +Flowering year round.  +
Berlandiera texana +Flowering Mar–Nov.  +
Berlandiera ×betonicifolia +Flowering Apr–Sep.  +
Berlandiera ×humilis +Flowering Mar–Jun(–Dec).  +
Berlandiera ×macrophylla +Flowering late spring–fall.  +
Bernardia incana +Flowering spring–summer  +, fruiting summer–fall.  +
Bernardia myricifolia +Flowering spring–summer  +, fruiting summer–fall.  +
Bernardia obovata +Flowering spring  +, fruiting summer–fall.  +
Berteroa incana +Flowering May–Sep.  +
Beta vulgaris subsp. maritima +Flowering spring–early fall.  +
Beta vulgaris subsp. vulgaris +Flowering spring–summer.  +
Betula alleghaniensis +Flowering late spring.  +
Betula cordifolia +Flowering late spring.  +
Betula glandulosa +Flowering late spring.  +
Betula kenaica +Flowering late spring.  +
Betula lenta +Flowering late spring.  +
Betula michauxii +Flowering late spring.  +
Betula minor +Flowering late spring.  +
Betula murrayana +Flowering late spring.  +
Betula nana subsp. exilis +Flowering late spring.  +
Betula nana subsp. nana +Flowering late spring.  +
Betula neoalaskana +Flowering late spring.  +
Betula nigra +Flowering late spring.  +
Betula occidentalis +Flowering late spring.  +
Betula papyrifera +Flowering late spring.  +
Betula pendula +Flowering late spring.  +
Betula populifolia +Flowering late spring.  +
Betula pubescens subsp. pubescens +Flowering late spring.  +
Betula pubescens subsp. tortuosa +Flowering late spring.  +
Betula pumila +Flowering late spring.  +
Betula uber +Flowering late spring.  +
Bidens amplissima +Flowering Aug–Oct.  +
Bidens aristosa +Flowering Aug–Oct(–Nov).  +
Bidens aurea +Flowering mostly Aug–Sep.  +
Bidens beckii +Flowering Jul–Sep.  +
Bidens bidentoides +Flowering Sep.  +
Bidens bigelovii +Flowering Sep.  +
Bidens bipinnata +Flowering (Jun–)Aug–Sep(–Oct).  +
Bidens cernua +Flowering late (Jul–)Aug–Sep(–Oct).  +
Bidens connata +Flowering Aug–Oct.  +
Bidens discoidea +Flowering Aug–Oct(–Nov).  +
Bidens eatonii +Flowering Sep–Oct.  +
Bidens frondosa +Flowering (Jun–)Aug–Sep(–Oct).  +
Bidens heterodoxa +Flowering Aug–Oct.  +
Bidens heterosperma +Flowering Sep–Oct.  +
Bidens hyperborea +Flowering Aug–Oct.  +
Bidens laevis +Flowering Aug–Oct(–Dec).  +
Bidens lemmonii +Flowering Sep–Oct.  +
Bidens leptocephala +Flowering Sep.  +
Bidens mitis +Flowering Sep–Nov.  +
Bidens pilosa +Flowering year round.  +
Bidens polylepis +Flowering Aug–Oct.  +
Bidens tenuisecta +Flowering (Jul–)Aug–Sep(–Oct).  +
Bidens trichosperma +Flowering Aug–Oct.  +
Bidens tripartita +Flowering Aug–Oct.  +
Bidens vulgata +Flowering Aug–Sep(–Oct).  +
Bigelowia nudata var. australis +Flowering Oct–May.  +
Bigelowia nudata var. nudata +Flowering Aug–Oct(–Nov).  +
Bigelowia nuttallii +Flowering Sep–Oct(–Nov).  +
Billieturnera helleri +Flowering year-round.  +
Bischofia javanica +Flowering Feb–Apr  +, fruiting Jul–Nov.  +
Bistorta bistortoides +Flowering Jul–Sep.  +
Bistorta officinalis +Flowering May–Aug.  +
Bistorta plumosa +Flowering May–Jun.  +
Bistorta vivipara +Flowering Jun–Sep.  +
Blennosperma bakeri +Flowering Feb–Apr.  +
Blennosperma nanum var. nanum +Flowering Feb–May.  +
Blennosperma nanum var. robustum +Flowering Feb–May.  +
Blepharipappus scaber +Flowering Apr–Sep.  +
Blepharizonia laxa +Flowering Jul–Nov.  +
Blepharizonia plumosa +Flowering Jul–Nov.  +
Bletia patula +Flowering Mar–May.  +
Bletia purpurea +Flowering Dec–May, sporadically all year.  +
Bloomeria clevelandii +Flowering spring (Apr–Jun).  +
Bloomeria crocea var. aurea +Flowering spring (Apr–Jun).  +
Bloomeria crocea var. crocea +Flowering spring (Apr–Jun).  +
Bloomeria crocea var. montana +Flowering spring (Apr–Jun).  +
Bloomeria humilis +Flowering spring.  +
Blutaparon vermiculare +Flowering year-round.  +
Blysmopsis rufa +Fruiting late summer.  +
Blyxa aubertii +Flowering summer–fall.  +
Boechera acutina +Flowering Jun–Jul.  +
Boechera arcuata +Flowering Mar–Jun.  +
Boechera atrorubens +Flowering Apr–May.  +
Boechera bodiensis +Flowering Jul–Aug.  +
Boechera breweri subsp. breweri +Flowering Mar–Jul.  +
Boechera breweri subsp. shastaensis +Flowering Mar–Jun.  +
Boechera burkii +Flowering Apr–May.  +
Boechera calderi +Flowering Jun–Aug.  +
Boechera californica +Flowering Mar–Jun.  +
Boechera canadensis +Flowering Apr–Jul.  +
Boechera cascadensis +Flowering Jun.  +
Boechera cobrensis +Flowering May–Jun.  +
Boechera collinsii +Flowering May–Jun.  +
Boechera consanguinea +Flowering May.  +
Boechera constancei +Flowering May.  +
Boechera covillei +Flowering Jul–Aug.  +
Boechera crandallii +Flowering May–Jun.  +
Boechera cusickii +Flowering Apr-mid May.  +
Boechera davidsonii +Flowering Apr–Jul.  +
Boechera dentata +Flowering Apr–Jun.  +
Boechera depauperata +Flowering Jun–Jul.  +
Boechera dispar +Flowering Apr–May.  +
Boechera divaricarpa +Flowering May–Jul.  +
Boechera drepanoloba +Flowering Jul–Aug.  +
Boechera duchesnensis +Flowering May.  +
Boechera elkoensis +Flowering Jul.  +
Boechera evadens +Flowering Jun.  +
Boechera falcatoria +Flowering May–Jun.  +
Boechera falcifructa +Flowering May–Jun.  +
Boechera fecunda +Flowering Apr–Jun.  +
Boechera fendleri +Flowering Apr–Jul.  +
Boechera fernaldiana subsp. fernaldiana +Flowering May–Jul.  +
Boechera fernaldiana subsp. vivariensis +Flowering Apr–Jun.  +
Boechera formosa +Flowering Apr–Jun.  +
Boechera fructicosa +Flowering Jun–Jul.  +
Boechera glareosa +Flowering May–Jun.  +
Boechera glaucovalvula +Flowering Mar–Apr.  +
Boechera goodrichii +Flowering Apr–May.  +
Boechera gracilenta +Flowering Apr–May.  +
Boechera gracilipes +Flowering Apr–Jun.  +
Boechera grahamii +Flowering May–Aug.  +
Boechera gunnisoniana +Flowering May–Jun.  +
Boechera harrisonii +Flowering May–Jun.  +
Boechera hastatula +Flowering Jun–Jul.  +
Boechera hoffmannii +Flowering Feb–Mar.  +
Boechera holboellii +Flowering Jul–Aug.  +
Boechera horizontalis +Flowering Jul–Aug.  +
Boechera howellii +Flowering Jun–Aug.  +
Boechera inyoensis +Flowering Apr–Jun.  +
Boechera johnstonii +Flowering Feb–Mar.  +
Boechera koehleri +Flowering Apr–May.  +
Boechera laevigata +Flowering Mar–May.  +
Boechera languida +Flowering May–Jun.  +
Boechera lasiocarpa +Flowering May–Jun.  +
Boechera lemmonii +Flowering Jun–Aug.  +
Boechera lignifera +Flowering Apr–May.  +
Boechera lincolnensis +Flowering Apr–May.  +
Boechera lyallii +Flowering Jun–Aug.  +
Boechera macounii +Flowering May–Jul.  +
Boechera microphylla +Flowering Apr–Jun.  +
Boechera missouriensis +Flowering Mar–Jun.  +
Boechera nevadensis +Flowering Jun.  +
Boechera ophira +Flowering May–Jun.  +
Boechera oxylobula +Flowering May–Jul.  +
Boechera paddoensis +Flowering Jul–Aug.  +
Boechera pallidifolia +Flowering Apr–Jun.  +
Boechera parishii +Flowering Mar–May.  +
Boechera pauciflora +Flowering May–Jun.  +
Boechera paupercula +Flowering Jun–Aug.  +
Boechera peirsonii +Flowering Jun–Sep.  +
Boechera pendulina +Flowering Apr–Jun.  +
Boechera pendulocarpa +Flowering Apr–Jul.  +
Boechera perennans +Flowering Feb–May.  +
Boechera perstellata +Flowering Apr–May.  +
Boechera pinetorum +Flowering May–Jul.  +
Boechera pinzliae +Flowering Jul.  +
Boechera platysperma +Flowering Jun–Aug.  +
Boechera polyantha +Flowering late Apr-early Jun.  +
Boechera porphyrea +Flowering late Mar-early May.  +
Boechera pratincola +Flowering Jun–Aug.  +
Boechera puberula +Flowering Apr–Jul.  +
Boechera pulchra +Flowering Mar–Jun.  +
Boechera pusilla +Flowering May–Jun.  +
Boechera pygmaea +Flowering May–Jul.  +
Boechera quebecensis +Flowering Jun–Jul.  +
Boechera rectissima +Flowering May–Jul.  +
Boechera repanda +Flowering Jun–Jul.  +
Boechera retrofracta +Flowering Apr–Aug.  +
Boechera rigidissima +Flowering Jul–Aug.  +
Boechera rollei +Flowering Aug.  +
Boechera rollinsiorum +Flowering Jun.  +
Boechera rubicundula +Flowering Apr–May.  +
Boechera saximontana +Flowering Jun–Jul.  +
Boechera schistacea +Flowering May–Jul.  +
Boechera serotina +Flowering Jul–Sep.  +
Boechera serpenticola +Flowering Mar–Jun.  +
Boechera shevockii +Flowering Jun.  +
Boechera shockleyi +Flowering Apr–May.  +
Boechera sparsiflora +Flowering Apr–Jun.  +
Boechera spatifolia +Flowering May–Aug.  +
Boechera stricta +Flowering May–Aug.  +
Boechera subpinnatifida +Flowering Mar–May.  +
Boechera suffrutescens +Flowering Jun–Aug.  +
Boechera texana +Flowering Apr.  +
Boechera tiehmii +Flowering Jun–Aug.  +
Boechera tularensis +Flowering Jun–Jul.  +
Boechera ultra-alsa +Flowering Jun–Jul.  +
Boechera villosa +Flowering May.  +
Boechera williamsii +Flowering May–Jun.  +
Boechera xylopoda +Flowering Mar–May.  +
Boechera yorkii +Flowering May.  +
Boehmeria cylindrica +Flowering summer–fall.  +
Boehmeria nivea +Flowering late summer–fall.  +
Boerhavia anisophylla +Flowering mid summer–early fall.  +
Boerhavia ciliata +Flowering late spring-mid fall.  +
Boerhavia coccinea +Flowering spring–winter [year-round].  +
Boerhavia coulteri var. coulteri +Flowering late spring–early fall.  +
Boerhavia coulteri var. palmeri +Flowering mid summer–early fall.  +
Boerhavia diffusa +Flowering mid winter–early fall [year-round].  +
Boerhavia erecta +Flowering early summer-mid fall.  +
Boerhavia gracillima +Flowering mid summer–late fall.  +
Boerhavia intermedia +Flowering summer–late fall.  +
Boerhavia linearifolia +Flowering mid spring–late summer.  +
Boerhavia megaptera +Flowering summer–fall.  +
Boerhavia pterocarpa +Flowering late summer.  +
Boerhavia purpurascens +Flowering late summer.  +
Boerhavia spicata +Flowering late summer–early fall.  +
Boerhavia torreyana +Flowering mid summer and early fall.  +
Boerhavia triquetra +Flowering summer–late fall.  +
Boerhavia wrightii +Flowering summer.  +
Bolandra californica +Flowering Jun–Jul.  +
Bolandra oregana +Flowering May–Jul.  +
Bolboschoenus fluviatilis +Fruiting summer.  +
Bolboschoenus glaucus +Fruiting summer.  +
Bolboschoenus maritimus subsp. maritimus +Fruiting summer.  +
Bolboschoenus maritimus subsp. paludosus +Fruiting spring–fall (south and lowland California), summer (north).  +
Bolboschoenus novae-angliae +Fruiting summer.  +
Bolboschoenus robustus +Fruiting spring–fall (south), summer (north).  +
Boltonia apalachicolensis +Flowering late Sep–Dec.  +
Boltonia asteroides var. asteroides +Flowering Jul–Nov.  +
Boltonia asteroides var. latisquama +Flowering Aug–Sep.  +
Boltonia asteroides var. recognita +Flowering Aug–Sep.  +
Boltonia caroliniana +Flowering Aug–Oct.  +
Boltonia decurrens +Flowering Aug–Sep.  +
Boltonia diffusa var. diffusa +Flowering Jul–Nov.  +
Boltonia diffusa var. interior +Flowering Sep–Oct.  +
Bommeria hispida +Sporulating summer–fall.  +
Bonellia macrocarpa subsp. macrocarpa +Flowering year-round.  +
Bontia daphnoides +Flowering Nov–Jun.  +
Borrichia arborescens +Flowering late spring–summer.  +
Borrichia frutescens +Flowering late spring–summer.  +
Borrichia ×cubana +Flowering late spring–summer.  +
Boschniakia rossica +Flowering Jun–Aug.  +
Botrychium acuminatum +Leaves appearing in midspring, dying in fall.  +
Botrychium ascendens +Leaves appearing in late spring to midsummer.  +
Botrychium biternatum +Leaves green over winter, sporophores seasonal, new leaves appearing in late spring–early summer.  +
Botrychium boreale +Leaves appearing in July and August.  +
Botrychium campestre +Leaves appearing in early spring and dying in late spring and early summer, long before those of associated moonworts.  +
Botrychium crenulatum +Leaves appearing in mid to late spring, dying in late summer  +, in extremely dry years of shorter duration or not appearing at all.  +
Botrychium dissectum +Leaves green over winter, new leaves appearing in late spring.  +
Botrychium echo +Leaves appearing in June, dying in September.  +
Botrychium gallicomontanum +Leaves appearing in midspring, dying in summer.  +
Botrychium hesperium +Leaves appearing in midspring, dying in early fall.  +
Botrychium jenmanii +Leaves green over winter, arising at variable times during last half of summer, meiosis as late as September.  +
Botrychium lanceolatum subsp. angustisegmentum +Leaves appearing in late spring or early summer, releasing spores later than most associated species, and dying as late as October.  +
Botrychium lanceolatum subsp. lanceolatum +Leaves usually drying up in midsummer together with other associated species.  +
Botrychium lunaria +Leaves appearing in spring, dying in latter half of summer.  +
Botrychium lunarioides +Leaves appearing in late fall and dying in early spring.  +
Botrychium matricariifolium +Leaves appearing in spring, dying in late summer.  +
Botrychium minganense +Leaves appearing in spring through summer.  +
Botrychium montanum +Leaves appearing in late spring to late summer.  +
Botrychium mormo +Leaves appearing in late spring to fall.  +
Botrychium multifidum +Leaves green over winter, appearing in spring.  +
Botrychium oneidense +Leaves green over winter, sporophores seasonal, new leaves appearing in spring.  +
Botrychium pallidum +Leaves appearing in late spring and early summer.  +
Botrychium pedunculosum +Leaves appearing in late spring, dying in early fall.  +
Botrychium pinnatum +Leaves appearing in June to August.  +
Botrychium pseudopinnatum +Leaves appearing in late spring to early fall.  +
Botrychium pumicola +Leaves appearing in summer.  +
Botrychium rugulosum +Leaves green over winter, appearing in midspring.  +
Botrychium simplex +Leaves appearing midspring to early fall.  +
Botrychium spathulatum +Leaves appearing late spring through summer.  +
Botrychium virginianum +Leaves seasonal, appearing in early spring and dying in late summer.  +
Boykinia aconitifolia +Flowering summer.  +
Boykinia intermedia +Flowering summer.  +
Boykinia major +Flowering summer(-early autumn).  +
Boykinia occidentalis +Flowering summer.  +
Boykinia richardsonii +Flowering summer.  +
Boykinia rotundifolia +Flowering early-mid summer.  +
Brachychiton populneus +Flowering (Jan–)May–Jul(–Nov).  +
Brachymenium macrocarpum +Capsules mature Apr–Aug (spring–summer).  +
Brachystigma wrightii +Flowering Aug–Oct  +, fruiting Oct–Dec.  +
Bradburia hirtella +Flowering late spring–early summer.  +
Bradburia pilosa +Flowering late spring–early summer.  +
Brandegea bigelovii +Flowering (Feb–)Mar–Apr(–later sporadically).  +
Brasenia schreberi +Flowering late spring–summer.  +
Brassia caudata +Flowering winter–summer (Jan–Aug).  +
Brassica elongata +Flowering Jun–Jul.  +
Brassica fruticulosa +Flowering Dec–Mar.  +
Brassica juncea +Flowering May–Sep.  +
Brassica napus +Flowering May–Sep.  +
Brassica nigra +Flowering Apr–Sep.  +
Brassica oleracea +Flowering May–Aug.  +
Brassica rapa +Flowering Apr–Sep.  +
Brassica tournefortii +Flowering Feb–Apr.  +
Braunia andrieuxii +Capsules mature spring.  +
Braunia secunda +Capsules mature spring.  +
Braya fernaldii +Flowering Jun–Jul.  +
Braya glabella subsp. glabella +Flowering Jun–Jul.  +
Braya glabella subsp. prostrata +Flowering Jun–Jul.  +
Braya glabella subsp. purpurascens +Flowering Jun–Jul.  +
Braya humilis subsp. ellesmerensis +Flowering Jun–Jul, fruiting Jul–Aug.  +
Braya humilis subsp. humilis +Flowering May–Jul.  +
Braya humilis subsp. maccallae +Flowering May–Jul.  +
Braya humilis subsp. porsildii +Flowering May–Jul.  +
Braya linearis +Flowering Jun–Jul.  +
Braya longii +Flowering Jun–Jul.  +
Braya pilosa +Flowering Jul–Aug.  +
Braya thorild-wulffii subsp. glabrata +Flowering Jul.  +
Braya thorild-wulffii subsp. thorild-wulffii +Flowering Jul.  +
Breynia disticha +Flowering and fruiting summer.  +
Brickellia amplexicaulis +Flowering Sep–Dec.  +
Brickellia atractyloides var. arguta +Flowering Apr–Jun.  +
Brickellia atractyloides var. atractyloides +Flowering Mar–Sep.  +
Brickellia atractyloides var. odontolepis +Flowering Apr–Jun.  +
Brickellia baccharidea +Flowering Oct–Apr.  +
Brickellia betonicifolia +Flowering Jul–Oct.  +
Brickellia brachyphylla +Flowering Jul–Oct.  +
Brickellia californica +Flowering Jul–Oct.  +
Brickellia chenopodina +Flowering Aug–Oct.  +
Brickellia cordifolia +Flowering Aug–Oct.  +
Brickellia coulteri var. brachiata +Flowering Mar–Oct.  +
Brickellia coulteri var. coulteri +Flowering Mar–Oct.  +
Brickellia cylindracea +Flowering Jun–Nov.  +
Brickellia dentata +Flowering Aug–Nov.  +
Brickellia desertorum +Flowering Sep–Mar.  +
Brickellia eupatorioides var. chlorolepis +Flowering May–Oct.  +
Brickellia eupatorioides var. corymbulosa +Flowering May–Oct.  +
Brickellia eupatorioides var. eupatorioides +Flowering May–Oct.  +
Brickellia eupatorioides var. floridana +Flowering Jun–Sep.  +
Brickellia eupatorioides var. gracillima +Flowering Aug–Nov, Apr.  +
Brickellia eupatorioides var. texana +Flowering Aug–Nov.  +
Brickellia floribunda +Flowering Aug–Oct.  +
Brickellia frutescens +Flowering Mar–Jun.  +
Brickellia grandiflora +Flowering Jul–Oct.  +
Brickellia greenei +Flowering Jul–Sep.  +
Brickellia hinckleyi var. hinckleyi +Flowering Jul–Oct.  +
Brickellia hinckleyi var. terlinguensis +Flowering Jul–Oct.  +
Brickellia incana +Flowering May–Oct.  +
Brickellia knappiana +Flowering Sep–Oct.  +
Brickellia laciniata +Flowering Aug–Nov.  +
Brickellia lemmonii var. conduplicata +Flowering Aug–Nov.  +
Brickellia lemmonii var. lemmonii +Flowering Aug–Nov.  +
Brickellia longifolia var. longifolia +Flowering Sep–Nov.  +
Brickellia longifolia var. multiflora +Flowering Sep–Nov.  +
Brickellia microphylla var. microphylla +Flowering Jul–Oct.  +
Brickellia microphylla var. scabra +Flowering Jul–Oct.  +
Brickellia nevinii +Flowering Aug–Nov.  +
Brickellia oblongifolia var. linifolia +Flowering May–Aug.  +
Brickellia oblongifolia var. oblongifolia +Flowering May–Aug.  +
Brickellia parvula +Flowering Aug–Oct.  +
Brickellia pringlei +Flowering Apr–Jun.  +
Brickellia rusbyi +Flowering Aug–Oct.  +
Brickellia simplex +Flowering Aug–Oct.  +
Brickellia venosa +Flowering Aug–Oct.  +
Brickellia veronicifolia +Flowering Sep–Oct.  +
Brickelliastrum fendleri +Flowering Jul–Sep(–Oct).  +
Brintonia discoidea +Flowering Aug–Oct.  +
Brodiaea appendiculata +Flowering spring (Apr–May).  +
Brodiaea californica subsp. californica +Flowering spring (late May–early Jun).  +
Brodiaea californica subsp. leptandra +Flowering summer (Jun).  +
Brodiaea coronaria subsp. coronaria +Flowering spring (Apr–Jun).  +
Brodiaea coronaria subsp. rosea +Flowering spring (late May–Jun).  +
Brodiaea elegans subsp. elegans +Flowering spring–summer (May–Jul).  +
Brodiaea elegans subsp. hooveri +Flowering spring.  +
Brodiaea filifolia +Flowering spring (Apr–May).  +
Brodiaea insignis +Flowering spring (May–Jun).  +
Brodiaea jolonensis +Flowering spring (Apr–May).  +
Brodiaea kinkiensis +Flowering spring (May–Jun).  +
Brodiaea minor +Flowering spring (Apr–early May).  +
Brodiaea orcuttii +Flowering spring (May).  +
Brodiaea pallida +Flowering spring (late May–early Jun).  +
Brodiaea purdyi +Flowering spring (Jun).  +
Brodiaea stellaris +Flowering spring (May–Jun).  +
Brodiaea terrestris subsp. kernensis +Flowering spring (Apr–Jun).  +
Brodiaea terrestris subsp. terrestris +Flowering spring (Apr–Jun).  +
Brosimum alicastrum +Flowering all year.  +
Brotherella canadensis +Capsules mature late fall–early spring.  +
Brotherella henonii +Capsule maturity unknown.  +
Brotherella recurvans +Capsules mature late fall.  +
Brotherella roellii +Capsules mature winter.  +
Broussonetia papyrifera +Flowering spring.  +
Bruchia bolanderi +Capsules mature summer.  +
Bruchia brevifolia +Capsules mature early spring.  +
Bruchia carolinae +Capsules mature late winter–spring.  +
Bruchia drummondii +Capsules mature spring.  +
Bruchia flexuosa +Capsules mature spring–summer.  +
Bruchia fusca +Capsules mature spring.  +
Bruchia hallii +Capsules mature late winter–spring.  +
Bruchia ravenelii +Capsules mature winter.  +
Bruchia texana +Capsules mature spring.  +
Bruchia vogesiaca +Capsules mature summer.  +
Brunnichia ovata +Flowering Jun–Jul.  +
Bryocrumia vivicolor +Capsule maturity unknown.  +
Bryoerythrophyllum columbianum +Sporophytes rare, capsules mature early spring (Mar).  +
Bryoerythrophyllum ferruginascens +Sporophytes unknown for the region of the flora.  +
Bryoerythrophyllum inaequalifolium +Sporophytes absent in the area of the flora.  +
Bryoerythrophyllum recurvirostrum +Capsules mature summer–fall (Jun–Sep).  +
Bryolawtonia vancouveriensis +Capsules mature spring.  +
Bryonia alba +Flowering Jun–Aug.  +
Bryonia dioica +Flowering Jun–Aug.  +
Bryophyllum daigremontianum +Flowering winter.  +
Bryophyllum delagoense +Flowering winter, spring.  +
Bryophyllum fedtschenkoi +Flowering winter–spring.  +
Bryophyllum gastonis-bonnieri +Flowering winter.  +
Bryophyllum pinnatum +Flowering winter–spring.  +
Bryoxiphium norvegicum +Capsules mature Jul.  +
Bryum argenteum var. argenteum +Capsules mature Apr–Jul (spring–summer).  +
Bryum argenteum var. majus +Capsules unknown.  +
Bryum argenteum var. muticum +Capsules unknown.  +
Bryum blindii +Capsules mature Jun–Aug (summer).  +
Bryum lanatum +Capsules mature May–Jul (spring–summer).  +
Bryum oblongum +Capsules mature Jun–Aug (summer).  +
Buchnera americana +Flowering May–Oct.  +
Buchnera floridana +Flowering May–Oct.  +
Buchnera obliqua +Flowering Aug–Sep.  +
Buckiella undulata +Capsules mature summer.  +
Buckleya distichophylla +Flowering Apr–May, Aug.  +
Buddleja davidii +Flowering May–Oct  +, fruiting Jul–Nov.  +
Buddleja indica +Flowering and fruiting year-round.  +
Buddleja lindleyana +Flowering Jun–Oct  +, fruiting Aug–Nov.  +
Buddleja madagascariensis +Flowering Mar–May  +, fruiting not known in continental United States.  +
Buddleja marrubiifolia +Flowering Feb–Aug  +, fruiting Jul–Oct.  +
Buddleja racemosa var. incana +Flowering May–Aug  +, fruiting Jul–Oct.  +
Buddleja racemosa var. racemosa +Flowering May–Aug  +, fruiting Jul–Oct.  +
Buddleja saligna +Flowering May–Sep  +, fruiting Jul–Oct.  +
Buddleja scordioides +Flowering May–Aug  +, fruiting Sep–Nov.  +