Arceuthobium campylopodum subsp. californicum

(Hawksworth & Wiens) Nickrent

Phytoneuron 2012-51: 10. 2012

Common names: Sugar pine dwarf mistletoe
Endemic
Basionyms: Arceuthobium californicum Hawksworth & Wiens
Treatment appears in FNA Volume 12. Treatment on page 431. Mentioned on page 429.
Plants forming witches' brooms. Stems bright yellow or green, 6–8(–14) cm; third internode 6–10.5(–16) × 1–1.5(–2) mm, dominant shoot 1.5–4 mm diam. at base. Staminate flowers 3.3 mm diam.; petals 3–4. Fruits 4 × 2.5 mm.

Phenology: Flowering Jul–Aug; fruiting Sep–Oct.
Habitat: Coniferous forests with sugar pine or western white pine.
Elevation: 600–2000 m.

Discussion

Meiosis occurs in July, with fruits maturing 13–14 months after pollination.

As the common name implies, subsp. californicum is parasitic primarily on Pinus lambertiana, secondarily on P. monticola. It is found from the Peninsular Ranges of San Diego County through the Sierra Nevada to the Cascade Range of Siskiyou County, as well as some locations in the Klamath Mountains. In some locations it is sympatric with subsp. campylopodum, and rarely both taxa can be found on the same host. It induces large witches' brooms on sugar pine and is considered a serious pathogen of that species.

References

None.

Lower Taxa

No lower taxa listed.