Guide to managing Bull Thistle, which grows as a rosette (ground-hugging form) in the first year, and then sends up stems and flowers in the second year, growing to 6 feet tall.
Donaldson, S., Hanson Mazet, W.
2010,
A Northern Nevada Homeowner’s Guide to Identifying and Managing Bull Thistle,
Extension | University of Nevada, Reno FS-10-19