Differences in types and functions.

1. Type differences. Lepidium is a common and drought-tolerant weed in North America. It belongs to the dicotyledonous poppy order. Lepidium is a plant of the genus Lepidium in the Brassicaceae family. The two plant species are different.

2. Function difference. North American Lepidium affects the normal growth of crops and is a weed. Lepidium has diuretic, cough-relieving and phlegm-reducing effects. The two functions are different.