Arceuthobium campylopodum subsp. siskiyouense

(Hawksworth

Wiens & Nickrent) Nickrent, Phytoneuron 2012-51: 10. 2012.

Common names: Knobcone pine dwarf mistletoe
Endemic
Basionym: Arceuthobium siskiyouense Hawksworth Wiens & Nickrent, Novon 2: 204. 1992
Treatment appears in FNA Volume 12. Treatment on page 433. Mentioned on page 429, 430.

Plants forming witches brooms. Stems brown, 6–8 (–10) cm; third internode 8–9 (–15) × 2 mm, dominant shoot 2–2.5 mm diam. at base. Staminate flowers 3 mm diam.; petals 3 or 4. Fruits 4 × 2.5 mm.


Phenology: Flowering Aug–Sep; fruiting Sep–Oct.
Habitat: Coniferous forests, especially closed-cone pine forests with knobcone pine.
Elevation: 400–1200 m.

Discussion

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

The principal host of subsp. siskiyouense is Pinus attenuata; rare hosts include P. contorta, P. jeffreyi, and P. ponderosa. Subspecies siskiyouense is endemic to the Klamath and Siskiyou mountains.

Selected References

None.

Lower Taxa

None.
Daniel L. Nickrent +
(Hawksworth +
Arceuthobium siskiyouense +
brown +, orange +, yellow +, olive green +  and yellowish green +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (?) +  and 0.3 cm3 mm <br />0.003 m <br /> (?) +
scale-like +
10 cm100 mm <br />0.1 m <br /> (22 cm220 mm <br />0.22 m <br />) +
3 cm30 mm <br />0.03 m <br /> (?) +  and 10 cm100 mm <br />0.1 m <br /> (?) +
Knobcone pine dwarf mistletoe +
spikelike +
Calif. +  and Oreg. +
400–1200 m. +
globose +  and pyriform +
3 cm30 mm <br />0.03 m <br /> (?) +
lenticular +
4 cm40 mm <br />0.04 m <br /> (?) +
2.5 cm25 mm <br />0.025 m <br /> (?) +
Coniferous forests, especially closed-cone pine forests with knobcone pine. +
terminal +  and axillary +
bisexual +  and unisexual +
0.9 cm9 mm <br />0.009 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
2 cm20 mm <br />0.02 m <br /> (?) +
connate +
scale-like +
pinnate +  and entire +
articulated +
asymmetric +  and symmetric +
yellowish green +
connate +  and distinct +
deltate +  and triangular +
Flowering Aug–Sep +  and fruiting Sep–Oct. +
2[-3]-carpellate +
Wiens & Nickrent) Nickrent, Phytoneuron +
mucilaginous +
0.33 cm3.3 mm <br />0.0033 m <br /> (?) +  and 0.55 cm5.5 mm <br />0.0055 m <br /> (?) +
pyriform +  and ellipsoid +
0.23 cm2.3 mm <br />0.0023 m <br /> (?) +  and 0.4 cm4 mm <br />0.004 m <br /> (?) +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
3 +  and 4 +
8 cm80 mm <br />0.08 m <br /> (10 cm100 mm <br />0.1 m <br />) +
pendulous +  and erect +
fanlike +
6 cm60 mm <br />0.06 m <br /> (8 cm80 mm <br />0.08 m <br />) +
undifferentiated +
Razoumofskya campylopoda +
Arceuthobium campylopodum subsp. siskiyouense +
Arceuthobium campylopodum +
subspecies +
spikelike +
mucilaginous +
evergreen +  and perennial +