Baccharis salicifolia aka Sticky Baccharis

Baccharis salicifolia, or seep willow, is an evergreen shrub. It belongs to the aster family, Asteraceae. Its range spans the southwestern United States, Mexico, and Central America. It also grows south through western South America to Chile and Argentina. It is not native to Britain or Ireland. In the wild, it grows beside streams in sandy or rocky thickets. It also occurs on damp plains and in fields.

The plant forms a clump of upright or spreading stems. Root suckers can help it form broad, dense thickets. Reference accounts place shrub height around 8–10 feet [2.4–3 metres]. The wider recorded range is 1–13 feet [0.3–4 metres]. In the southern part of its range, trees can reach 20 feet [6 metres]. Its form and leaves can change with the season. This variation once led botanists to give some plants different names.

The leaves grow in an alternate pattern along the stems. Each narrow, lanceolate leaf measures 3–5 inches [8–13 centimetres] long. Fine teeth line the edges, with gaps between them. The upper face is glossy green; the lower face is paler. Some leaves feel sticky to the touch. Young stems are green and sticky, then turn light or golden brown. Their centres contain a large amount of pith. Older bark is grey-brown, with shallow ridges and reddish grooves. Narrow, raised leaf scars mark the twigs.

Male and female flowers grow on separate plants. Small white flower heads can appear through most of the year. They gather at stem tips or cluster where leaves join stems. Each head measures about half an inch [1.3 centimetres] across. Insects pollinate the flowers, and bees and butterflies visit for nectar. The fruit is a small achene with long white hairs. Plants can produce many fruits, which wind carries away.

Seep willow grows as an ornamental and ground cover. People also use it in projects that hold soil in place. It prefers climates with little frost. It can withstand brief cold spells of 14–23°F [-10 to -5°C]. The supplied species account reports no known hazards. People collect it for local medicine and food during shortages. That account does not establish safe portions or edible parts.