Plant of the Week
Sugarstick (Allotropa virgata Torr. & A. Gray ex A. Gray)
By Russell Holmes
Allotropa virgata is in the Ericaceae (Heath Family) which contains roughly 1400 species species worldwide. It is among a unique group of species, referred to as the Monotropoideae, that do not have chlorophyll and are incapable of photosynthesis. These plants obtain nutrients and carbohydrate from fungi that are associated with their roots and with the roots of various species of conifer or hardwood trees. The fungi are known as mycorrhizae and transport nutrients and photosynthate from host trees to the non-photosynthetic Allotropa virgata.
Mature plants of Allotropa virgata have red and white vertically striped stems up to 40 cm (16 inches) tall. Stems arise from a fibrous root system. Branch roots with adventitious buds produce additional stems. Leaves are small, scale like, and are pink to yellow-brown in color. Flowers occur in the axils of bracts and are arranged in a terminal spike-like raceme 5 to 20 cm (2.0 to 7.9 inches) long. Flowers have five white, pink, or brown sepals approximately 5 mm (0.2 inches) long but do not have any petals. Ten purplish stamens approximately twice as long as the sepals surround the pistil.
Candystick is a regional endemic ranging from British Columbia to California from the Cascades to near the coast. Disjunct populations have been documented in Idaho and Montana. Habitat is described as closed canopy coniferous forests with deep humus at elevations ranging from near sea level to approximately 3000 m (9,800 feet). Tree species associated with populations include Pseudotsuga menziesii (Douglas-fir), Tsuga heterophylla (western hemlock), Abies grandis (grand fir), Abies amabilis (silver fir), Abies magnifica (red fir), Pinus contorta (lodgepole pine), and Lithocarpus densiflorus (tanoak). Stand age is variable but the largest sugarstick populations occur in old-growth.
Candystick was first collected in the Washington Cascades by the Wilkes expedition in the late 1800s.