Comprehensive DescriptionRead full entry
General: Rose Family (Rosaceae). Pacific silverweed is a low-growing perennial native herb which spreads by creeping stolons. It often forms dense tangles. The pinnately compound and alternate leaves are all basal, glossy green, with silver undersides. The leaflets are deeply notched and toothes, 3-50 cm long, with 5-10 leaflets per side. The leaves dry out and become brown in the winter, but remain intact. The buttercup-like yellow flowers have 5 petals, 5 sepals, and have many stamens and pistils. Pacific silverweed flowers form singly at the nodes of the stolons. The petals are 7-20 mm long. The 2 mm fruits are oval, flattened, and dark red-brown.
Distribution: For current distribution, please consult the Plant Profile page for this species on the PLANTS Web site. It is found in the Pacific Northwest and New England into Labrador and Newfoundland. It is found at elevations below 150 m throughout coastal North America and Asia.
Habitat: Pacific silverweed typically occurs in high tidal marshes, at or above the mean high water, where it is often associated with tufted hairgrass (Deschampsia caespitosa) and Lyngby sedge (Carex. lyngbyei). It can also be found in nontidal freshwater meadows and marshes. In these situations, it is often associated with creeping buttercup (Ranunculus repens), several species of grasses and sedges, and the invasive reed canarygrass (Phalaris arundinacea).