Digitaria

Digitus is the Latin word for "finger", and they are distinguished by the long, finger-like inflorescences they produce.

They can be toasted, ground into a flour, made into porridge or fermented to make beer.

The seeds germinate in the late spring and early summer and outcompete the domesticated lawn grasses, expanding outward in a circle up to 30 cm (12 in) in diameter.

In the autumn when the plants die, they leave large voids in the lawn.

The voids then become prime areas for the crabgrass seeds to germinate the following season.

Large crabgrass seedhead 2 - 9 spikelets
Large crabgrass seedhead raceme