The Musk Thistle is another European introduction. It is somewhat dependent on a specific habitat, since it requires a calcareous (lime-rich) soil. Pittsylvania County has several outcrops of limestone sites in the northwestern quarter of the county. Some geologists believe these sites were hydrothermal in origin; that is, the result of pre-existing rocks' being altered by extremely hot water and pressure. Some notions are that the water may have been of magmatic origin.
When heading north from Museville on VA 626 and crossing the Canada Bridge over the Pigg River, musk thistles are soon found nearby. After a steep climb the road descends alongside the entrance to the old PawPaw Plantation, once owned by the friendly and fascinating Rison brothers. Musk thistles abound on this farm in localized limestone soils. Although a pesky weed in pastures, its unusual form and rose-colored flowers rarely go unnoticed. Viewed from certain angles, the flowering head of this species appears bent over — hence, the other name, “nodding thistle.”