Archive for August 27, 2008

Wednesday, August 27, 2008

The Last of the Thistles

Carlina acaulis growing in Bonnefont Garden.

Since we have received appreciations from so many thistle lovers, I thought I would finish out the series with the carline thistles, the last thistles in our medieval plant collection to bloom. Unlike other thistles, their flowers have a daisy form consisting of a disk with rayed petals. They are dry flowers of the “ever-lasting” type, sometimes described as straw flowers. The carline thistles are plants of poor, dry soils. The U.S.D.A. lists the common carline thistle, Carlina vulgaris, as an invasive weed reported in New York and New Jersey, but no other state, although I have never observed them in either. Has anyone seen it in their locale? (The U.S.D.A. site notes that it is not necessarily the case that a plant is established only in the states indicated by shading on their map. It may well grow elsewhere, but its presence has not been reported to the U.S.D.A.)

The perennial stemless species, Carlina acaulis, native to Europe, strongly resembles the closely related Eurasian biennial Carlina vulgaris, except that the rosette of spiny leaves lies close to the ground, while the common carline thistle has a short stem. The leaves of C. acaulis are also longer than those of C. vulgaris. Read more »