Black-Grass: What you need to know
Black-grass thrives on heavy land, particularly where drainage is poor. On light land it is a problem on wetter areas. About 80% of seeds germinates in the autumn. Hot, dry summers see strong early autumn-germination; cool wet autumns see increased dormancy and delayed germination. Increasingly a major problem throughout England and worsening through herbicide resistance.
Description
Tall erect annual. Compact flower spike 3 - 13 cm; narrow and pointed, often tinted purple. Seedling leaf sheath often purple.
Black-Grass Ligule
Medium: 2.5 mm. Blunt and finely serrated.
Auricles: Absent.
Leaf blade: Bluish-green, short, flat and hairless. Usually rough with well-defined keel and usually rolled.
What does black-grass look like?
Black-grass ligule
Black-grass young plant
Black-grass flower head. Photo © Nigel Cattlin/FLPA