Origin:
Native to Europe and now widespread in the United States.
Biology:
A summer annual grass weed, found in virtually any situation – row crops, orchards, pastures, roadsides, landscape, turf. Seeds germinate from very early spring throughout the summer months, and plants mature from late spring through the summer into early fall. Lower joints of the stems also tend to extend roots where they touch the ground, and the plants will spread laterally in this manner.
Identification:
One of two principal species of crabgrass, Large Crabgrass may be distinguished from Smooth Crabgrass by its larger, hairy leaves. Mature plants may be prostrate or upright, depending on the growing condition. In regularly mowed turf they adapt with lower stems. Stems may be as long as 28 inches, and are branched at the base. Stems tend to be thin and weak. Leaves are light green and up to about 7 inches long. The edges of the leaf blades are covered with fairly long hairs. The flower head is arranged umbrella-like, consisting of from 3 to 11 slender branches that may be up to 4 inches long. The branches arise from separate but very close points at the end of the stem, or a few may arise from the same point. Flowers are arranged on one side of each branch.
Characteristicts Important to Control:
Germination once soil temperatures have risen sufficiently. In the west generally this is by the first of March.
