Stemless carline thistle

Carlina acaulis (stemless carline thistle, silver thistle) is a strikingly low-growing perennial in the daisy family (Asteraceae), forming a flat basal rosette of stiff, deeply pinnatilobate leaves with strongly spiny-toothed margins, the rosette reaching about 20 cm in diameter. True to its name, the plant is essentially stemless: a single large solitary flower head sits at the centre of the rosette directly on the ground (or, in subspecies caulescens, on a very short stem). The head can reach 7–15 cm across and is surrounded by many spreading rows of dry, papery, silvery-white to straw-yellow inner involucral bracts that simulate ray florets, encircling a broad disc of tubular yellowish-brown to pinkish florets that bloom from July to September. The fruit is a hairy achene topped with a feathery pappus. Native to the mountain meadows, chalk grasslands, and dry stony pastures of central and southern European Alpine and sub-Alpine regions from lowland valleys up to about 2,800 m, the flower head famously closes in damp weather.