Corydalis yanhusuo is a plant species in the genus "Corydalis". Acidic soils support such plants as bilberry, climbing corydalis and heath bedstraw. The largest genus is "Corydalis" (with 470 species). English common names include yanhusuo, corydalis, and Asian corydalis. Particularly common here are early bloomers such as the intermediate corydalis and fern-leaved corydalis. Many of the species in "Corydalis" contain alkaloids like canadineand corydaline, which blocks calcium. The caterpillars feed exclusively on "Corydalis" species. Here, the forest floor is spread with anemones, corydalis, scented honeysuckle and moss. The Chinese name for "Corydalis yanhusuo" is "yan hu suo" (). Ceratocapnos claviculata, the climbing corydalis, is a weak scrambling plant in the family Papaveraceae. Corydalis flavula (yellow fumewort, yellow harlequin, fume-root, yellow fumitory; syn. Corydalis nobilis, the Siberian corydalis, is a perennial plant native to Siberia, Xinjiang and Kazakhstan. "Corydalis flavula" is a state threatened plant in Michigan. Chinese traditional medicine used the boiled and dried tubers of "Corydalis yanhusuo" ("yanhusuo"). Climbing corydalis tends to grow on the edges of woodlands and previously wooded sites.