Annual vernal grass

Anthoxanthum aristatum is a small, tufted annual grass of the Poaceae family, typically only 10 to 40 centimetres tall, with slender, geniculately ascending culms branching at the base and arising from a shallow, fibrous root system. The flat, narrowly linear, light green leaf blades are 2 to 8 centimetres long and 2 to 5 millimetres wide, with a short, blunt membranous ligule about 1 to 3 millimetres long and smooth, slightly inflated sheaths. The inflorescence is a slender, narrowly ovoid to oblong, somewhat lobed and interrupted spike-like panicle 1 to 4 centimetres long, with crowded, lustrous, pale green to yellowish spikelets each about 6 to 9 millimetres long. Each spikelet contains a single fertile floret subtended by two sterile lemmas that bear conspicuous geniculate, dorsally inserted brown awns 4 to 9 millimetres long protruding from the spike, with the upper glume distinctly longer than the lower. When dried the plant exudes the strong, sweet, vanilla-like scent of coumarin. Native to the western Mediterranean, it is naturalised widely as a weed of sandy, acidic arable and waste ground.