Bidens bipinnata is named for its three compound leaves or pinnate leaves. Its stem is nearly cylindrical, slightly quadrangular, and its petiole has extremely narrow wings. Its leaves are usually strip-shaped or strip-shaped lanceolate, and its leaf edge has coarse serrations. Its fruit is 3-4.5mm long and 1.5mm-2mm wide, belonging to achene. It is more common in roadside and riverside wetland, the whole plant of herbs can be used as medicine, with the effect of detoxification and anti-inflammatory
This kind of Bidens is different from Bidens pinnatifida. Its leaves are not divided and needle shaped. It is named for its willow like shape. Its leaf edge also has sparse serrations, the stem is nearly cylindrical, and the fruit is achene, which is narrow wedge-shaped, with four edges, 5-6.5mm long, larger than the fruit of Bidens bipinnata. Similarly, it can also be used as herbal medicine, has the effect of detoxification and stasis.
The stem of Bidens bipinnata is obtuse and quadrangular, and the lower part has trifid or undivided leaflets, and the middle part has pinnate compound leaves. The elliptic leaflets grow on both sides, and the top leaflets are elliptical, trifid or undivided. The fruit is also achene, black, 7-13 mm long. Its special feature is that it has white ligulate flowers, 5-8mm in length and 3.5-5mm in width. It can also be used as medicine, which is different from other two kinds of Bidens.
To sum up, as a common Chinese medicine, Bidens bipinnata is mainly divided into three kinds: Bidens pinnatifida, Bidens lanceolata and Bidens bipinnata. They have their own morphological characteristics as well as common points. I hope you can identify the species of Bidens when you meet Bidens in your life after you have made the above points clear
