Wildflowers at Kowloon Reservoir. Bidens pilosa / White-flowered Spanish Needle: there are three main varieties. The first is the commonly seen railway beggar-ticks (*Bidens pilosa* L. var. *radiata* Sch.), which features robust stems and much larger flower heads. Another variety is called small-flowered Spanish needle (*Bidens pilosa* L. var. *minor* (Blume) Sherff), where the entire flower appears small, especially its ray florets, and can often be found along roadsides in central and southern regions as a well-known folk herb. The third variety is the typical Spanish needle (*Bidens pilosa* L.), characterized by having only yellow disc florets without any white ray florets, giving the entire flower a yellow appearance.
