and Arctic tundra, covering large areas of Canada, Alaska, northern Europe, and Siberia. Variation in nutrients and climate produces variation in size
5 KB (520 words) - 22:36, 5 November 2020
2 mm) or aborted late in development. Poa sect. Abbreviatae includes five North American species, two of which also grow in arctic regions of the Eastern
3 KB (383 words) - 17:25, 11 May 2021
at high elevations in the western cordillera, extending eastward onto the northern prairies, and disjunctively in the Canadian arctic (Caribou Hills). It
6 KB (442 words) - 20:52, 5 November 2020
those taxa that were traditionally placed in Physaria, in the strict sense, where replum shape is sometimes helpful in separating species. The valves of didymous-fruited
34 KB (1,355 words) - 20:43, 12 April 2023
primordia, discussed in detail by Z. Iwatsuki and R. A. Pursell (1980). These structures are weakly developed in species found in the Western Hemisphere
26 KB (1,714 words) - 22:26, 5 November 2020
oblanceolate, monomorphic or varying in size according to seasonal growth patterns; juvenile (basal or proximal) leaves mostly larger than mature (terminal or
8 KB (770 words) - 21:25, 5 November 2020
North America, Eurasia, montane to arctic areas. Species ca. 40 (3 in the flora). In Rhodiola, inflorescences are borne in axils of scale leaves on the rootstocks
4 KB (321 words) - 23:42, 5 November 2020
closely related to S. virgaurea, the type species of the genus, native to mostly arctic and alpine regions of Eurasia. Plants of S. multiradiata from the Rocky
5 KB (454 words) - 16:04, 30 January 2023
Temperate to arctic regions of the Northern Hemisphere and scattered in cooler regions of the tropics and Southern Hemisphere. Species ca. 45 (19 in the flora)
10 KB (436 words) - 21:44, 5 November 2020
(polyploidy widespread in the genus). Almost worldwide, but mostly in temperate regions of both hemispheres, some taxa occur in many regions of the world
37 KB (831 words) - 13:59, 3 June 2022
Pleuropogon is a genus of five hydrophilous species, one circumboreal in the arctic, the other four restricted to the Pacific coast of North America, extending
5 KB (376 words) - 17:22, 11 May 2021
x = 11, 12. Arctic and temperate North America, Europe, Asia. Species ca. 50 (4 in the flora). Bistorta often is included in Polygonum in the broad sense
5 KB (348 words) - 23:08, 5 November 2020
(Russian Far East, Siberia). Subspecies 2 (2 in the flora). Silene involucrata is a very variable circumpolar and arctic-alpine species complex. Many of the variants
4 KB (381 words) - 15:43, 27 October 2021
plumose. x=7 or 8. Nearly worldwide, primarily in cooler temperate and arctic regions. Species ca. 150 (25 in the flora). The taxonomy of Anemone continues
16 KB (1,220 words) - 20:37, 6 November 2020
to temperate and arctic regions of North America and Eurasia. Species ca. 115 (4 in the flora). Centers of diversity for Achillea are in Europe and Asia
6 KB (563 words) - 20:56, 5 November 2020
staminate catkins in 1 cluster of 2–4, formed late in growing season before flowering and exposed during winter; pistillate catkins in 1 or more clusters
5 KB (379 words) - 14:55, 29 February 2024
persistent. Achenes usually trigonous, included in perygynium. Mainly high mountains of Asia, a few in arctic and subarctic regions and high mountains of Northern
4 KB (342 words) - 21:40, 5 November 2020
America, ranging from arctic to subtropics in East Asia and Cordilleran North America and Central America. Species ca. 45 (12 in the flora). Cribb, P.
8 KB (293 words) - 22:11, 5 November 2020
papillose. North America, Europe, arctic and temperate Asia, Atlantic Islands (Azores, Iceland, Madeira). Species 8 (6 in the flora). Niphotrichum comprises
6 KB (564 words) - 22:26, 5 November 2020
1–5, longitudinally ribbed. x = 10, 21, 22 Worldwide except arctic and antarctic regions. In Lemna the connection to the mother frond is formed by a thin
5 KB (286 words) - 21:30, 5 November 2020