''Digitaria'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of plants in the grass family native to tropical and warm temperate regions but can occur in tropical, subtropical, and cooler temperate regions as well. Common names include crabgrass, finger-grass, and fonio. They are slender

monocotyledon Monocotyledons (), commonly referred to as monocots, ( Lilianae '' sensu'' Chase & Reveal) are flowering plants whose seeds contain only one embryonic leaf, or cotyledon. A monocot taxon has been in use for several decades, but with various ranks ...

ous annual and perennial lawn, pasture, and forage plants; some are often considered lawn pests. ''Digitus'' is the

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

word for "finger", and they are distinguished by the long, finger-like

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

s they produce. Large-crabgrass-11258-seedhead2

Uses

The seeds are edible, most notably those of fonio ('' Digitaria exilis'' and '' Digitaria iburua''), ''

Digitaria sanguinalis ''Digitaria sanguinalis'' is a species of Poaceae, grass known by several common names, including hairy crabgrass, hairy finger-grass, large crabgrass, crab finger grass, purple crabgrass. It is one of the better-known species of the genus ''Digi ...

'', as well as '' Digitaria compacta''. They can be toasted, ground into a

flour Flour is a powder made by Mill (grinding), grinding raw grains, List of root vegetables, roots, beans, Nut (fruit), nuts, or seeds. Flours are used to make many different foods. Cereal flour, particularly wheat flour, is the main ingredie ...

, made into

porridge Porridge is a food made by heating, soaking or boiling ground, crushed or chopped starchy plants, typically grain, in milk or water. It is often cooked or served with added flavourings such as sugar, honey, fruit, or syrup to make a sweet cereal ...

or fermented to make

beer Beer is an alcoholic beverage produced by the brewing and fermentation of starches from cereal grain—most commonly malted barley, although wheat, maize (corn), rice, and oats are also used. The grain is mashed to convert starch in the ...

. Fonio has been widely used as a

staple crop A staple food, food staple, or simply staple, is a food that is eaten often and in such quantities that it constitutes a dominant portion of a standard diet for an individual or a population group, supplying a large fraction of energy needs an ...

in parts of

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

. It also has decent nutrient qualities as a

forage Forage is a plant material (mainly plant leaves and stems) eaten by grazing livestock. Historically, the term ''forage'' has meant only plants eaten by the animals directly as pasture, crop residue, or immature cereal crops, but it is also used m ...

for cattle.

Lawns

The prevalent species of ''Digitaria'' in

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

are large crabgrass (''D. sanguinalis''), sometimes known as hairy crabgrass; and smooth crabgrass (''D. ischaemum''). These species often become problem

weed A weed is a plant considered undesirable in a particular situation, growing where it conflicts with human preferences, needs, or goals.Harlan, J. R., & deWet, J. M. (1965). Some thoughts about weeds. ''Economic botany'', ''19''(1), 16-24. Pla ...

s in lawns and gardens, growing especially well in thin lawns that are watered lightly, under-fertilized, and poorly drained. They are annual plants, and one plant is capable of producing 150,000 seeds per season. The seeds germinate in the late spring and early summer and outcompete the domesticated lawn grasses, expanding outward in a circle up to 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.

Biological control Biological control or biocontrol is a method of controlling pests, whether pest animals such as insects and mites, weeds, or pathogens affecting animals or plants by using other organisms. It relies on predation, parasitism, herbivory, or o ...

is preferable over

herbicide Herbicides (, ), also commonly known as weed killers, are substances used to control undesired plants, also known as weeds.EPA. February 201Pesticides Industry. Sales and Usage 2006 and 2007: Market Estimates. Summary in press releasMain page f ...

use on lawns, as crabgrass emergence is not the cause of poor lawn health but a symptom, and it will return annually if the lawn is not restored with fertilization and proper watering. Crabgrass is quickly outcompeted by healthy lawn grass because, as an annual plant, crabgrass dies off in autumn and needs open conditions for its germination the following spring.

Selected species

*'' Digitaria ammophila'' (Benth.) Hughes – silky umbrella grass *'' Digitaria bicornis'' (Lam.) Roemer & J.A.Schultes ex Loud. – Asian crabgrass *'' Digitaria brownii'' (Roem. & Schult.) Hughes – cotton panic grass *'' Digitaria californica'' (Benth.) Henrard – Arizona cottontop *'' Digitaria ciliaris'' (Retz.) Koeler – summer grass, southern crabgrass *''

Digitaria cognata ''Digitaria cognata'' is a species of grass known by the common names fall witchgrass,''Digitaria cogna ...

'' (Schult.) Pilg. – fall witchgrass, Carolina crabgrass, mountain hairgrass *'' Digitaria compacta'' (Roth ex Roem. & Schult.) Veldkamp *'' Digitaria cruciata'' (Nees) A. Camus *'' Digitaria ctenantha'' (F.Muell.) Hughes – comb finger grass *'' Digitaria didactyla'' Willd. – Queensland blue couch *'' Digitaria divaricatissima var. macractinia'' (Benth.) Heather L.Stewart & N.G.Walsh *'' Digitaria eriantha'' Steud. – pangolagrass, Smuts finger grass, woolly finger grass *'' Digitaria exilis'' (Kippist) Stapf – white fonio *'' Digitaria filiformis'' (L.) Koeler – slender crabgrass *'' Digitaria gracillima'' (Scribn.) Fernald – longleaf crabgrass *'' Digitaria horizontalis'' Willd. – Jamaican crabgrass *'' Digitaria iburua'' Stapf – Black fonio *'' Digitaria insularis'' (L.) Fedde – sourgrass *'' Digitaria ischaemum'' (Schreb.) Schreb. ex Muhl. – smooth crabgrass, small crabgrass, smooth finger grass *'' Digitaria longiflora'' (Retz.) Pers. – Indian crabgrass *'' Digitaria milanjiana'' (Rendle) Stapf – Madagascar crabgrass *'' Digitaria nuda'' Schumacher – naked crabgrass *'' Digitaria pauciflora'' Hitchc. – twospike crabgrass *'' Digitaria platycarpha'' (Trin.) Stapf *'' Digitaria petelotii'' Henrard *'' Digitaria radicosa'' (C.Presl) Miq. – trailing crabgrass *''

'' (L.) Scop. – hairy crabgrass, large crabgrass *'' Digitaria seriata'' Stapf – Sandveld fingergrass *'' Digitaria setigera'' Roth ex Roemer & J.A.Schultes – East Indian crabgrass *'' Digitaria serotina'' (Walt.) Michx. – dwarf crabgrass *'' Digitaria stenotaphrodes'' (Nees ex Steud.) Stapf *'' Digitaria texana'' A.S.Hitchc. – Texas crabgrass *'' Digitaria velutina'' (Forssk.) P.Beauv – velvet crabgrass *'' Digitaria villosa'' (Walt.) Pers. – shaggy crabgrass *'' Digitaria violascens'' Link – violet crabgrass

References

External links

* * {{Authority control Digitaria Poaceae genera Cereals