Digitaria

From Freepedia

(Redirected from Crabgrass)

Digitaria

Scientific classification

Kingdom:	Plantae
Division:	Magnoliophyta
Class:	Liliopsida
Order:	Poales
Family:	Poaceae
Subfamily:	Panicoideae
Genus:	Digitaria Haller

Species

See text

Digitaria is a genus of about 300 species of grass (family Poaceae) native to tropical and warm temperate regions. Common names include crabgrass, finger-grass, and fonio. They are slender monocotyledonous annual and perennial lawn, pasture, and forage plants; some are often considered lawn pests. Digitus is the Latin word for "finger", and they are distinguished by the long, finger-like inflorescences they produce.

All crabgrasses have similar growth habits and flowering structures, but species are separated by minor differences in the flower structures and leaf pubescence. They typically have spreading stems with wide flat leaf blades that lay on the ground with the tips ascending. The inflorescence is a panicle in which the spike-like branches are arranged in digitate fashion. The spikelets are arranged in two rows on an angled or winged rachis. Each spikelet has two florets, only one of which is fertile. The first bracts at the base of the spikelets are either very minute or absent (Cholewa & Bell).

Crabgrass seed has a long germination period; if conditions are right, it can germinate throughout the growing season. Crabgrasses occur in tropical, subtropical, and temperate regions of both hemispheres.

The most commonly known species of Digitaria are Large Crabgrass (D. sanguinalis) and Smooth Crabgrass (D. ischaemum), which are often considered problem weeds. First, they are annual plants, and one plant is capable of producing 150,000 seeds per season. The plants invade lawns during the spring and summer and then leave large voids in the fall and winter when they die off. Second, crabgrass has an ungainly texture that often interrupts the uniformity of a lawn. In vegetable gardens, crabgrass can quickly out-compete desirable plants, causing considerable yield reductions.

Still, despite their weediness, crabgrasses do have a few redeeming qualities. The seeds, most notably those of fonio, can be toasted and ground into a flour, which can be used to make porridge or fermented to make beer. It also has decent nutrient qualities as a forage for cattle.