This is the only native on this page. It is a bushy, low, spreading plant with many beautiful, bright yellow flowers, each about 1 cm across with 5 to many stamens. In all the plants of this genus, 2 of the 5 sepals are narrower than the others. In this particular species, the 2 outer sepals are linear, while the 3 inner ones are wide and pointed. Stems are slender and rush-like, but all bear small, linear to narrowly lanceolate leaves. Photo #3 by CJH.
There is another variety (var. vulgare), not shown, which is very similar. However, it is taller (30–45 cm), with more flowers per stem (4–18) and longer outer sepals. It is found at higher elevations (50–1200 m).