The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

slender crabgrass

common crabgrass, crabgrass, digitaire sanguine, hairy crab grass

Habit Plants annual, or short-lived perennials; cespitose, not rhizomatous. Plants annual.
Culms

(10)25-150 cm, erect or decumbent, branching, sometimes rooting at the lower nodes;

nodes 3-6.

20-70(112), often decumbent and rooting at the lower nodes.

Sheaths

keeled, basal sheaths usually with papillose-based hairs, rarely glabrous;

ligules 0.3-1.5 mm;

blades 2-18 cm long, 1-6 mm wide, flat or involute, glabrous, scabrous, or pilose.

keeled, usually sparsely pubescent with papillose-based hairs;

ligules 0.5-2.6 mm;

blades 2-11(14) cm long, 3-8(12) mm wide, usually with papillose-based hairs on both surfaces, sometimes glabrous.

Panicles

with 2-7 spikelike primary branches, these digitate or the rachises to 1 cm;

longest primary branches 20-25 cm, axes triquetrous, not winged, with spikelets in unequally pedicellate groups of 3(-5) on the basal ½ (J.

with 4-13 spikelike primary branches, these subdigitate or on rachises to 6 cm;

primary branches 3-30 cm long, 0.7-1.5 mm wide, flattened and winged, wings more than 1/2 as wide as the midribs, lower and middle portion of the branches bearing spikelets in unequally pedicellate pairs, pedicels not adnate to the branches;

secondary branches rarely present.

Spikelets

1.3-2.8 mm.

homomorphic, 1.7-3.4 mm long, 0.7-1.1 mm wide.

Lower glumes

absent or to 0.1 mm;

upper glumes 1-2 mm long, from 3/4 to almost as long as the spikelets, almost glabrous or sparsely to densely pubescent with clavate to capitate hairs (use 20x magnification), glume apices rounded;

lower lemmas equaling the spikelets, glabrous or glandular-pubescent, 5-7-veined, veins unequally spaced, outer 3 veins on each side closer to each other than the midvein is to the inner lateral veins;

upper lemmas 1.3-2 mm, apiculate, dark brown at maturity;

anthers 0.3-0.6 mm.

0.2-0.4 mm long, veinless;

upper glumes 0.9-2 mm, 1/3 – 1/2 as long as the spikelets, 3-veined, pubescent on the margins;

lower lemmas usually exceeded or equaled by the upper florets, sometimes exceeding them but by no more than 0.2 mm, glabrous, 7-veined, lateral (or all) veins scabrous throughout or smooth on the lower (1/3)1/2 and scabrous distally, 3 middle veins usually widely spaced, remaining veins on each side close together and near the margins;

upper lemmas 1.7-3 mm, yellow or gray, frequently purple-tinged when immature, often becoming brown at maturity;

anthers 0.5-0.9 mm.

Wipff

, pers.

Comm

.).

2n

= 36, 54.

= 36, 28, 34, 54.

Digitaria filiformis

Digitaria sanguinalis

Distribution
from FNA
AL; AR; CT; DC; DE; FL; GA; IA; IL; IN; KS; KY; LA; MA; MD; MI; MO; MS; NC; NH; NJ; NY; OH; OK; PA; RI; SC; TN; TX; VA; VT; WV
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; AZ; CA; CO; CT; DC; DE; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; PR; AB; BC; MB; NS; ON; PE; QC; SK
[WildflowerSearch map]
[BONAP county map]
Discussion

Digitaria filiformis grows throughout the warmer parts of the eastern United States, van filifomis the most widespread of its varieties, extending into Mexico.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Digitaria sanguinalis is a weedy Eurasian species that is now found in waste ground of fields, gardens, and lawns throughout much of the world, including the Flora region.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Lower lemmas glabrous
var. laeviglumis
1. Lower lemmas pubescent.
→ 2
2. Basal leaf sheaths glabrous; cauline blades about 1 mm wide, folded or involute
var. dolichophylla
2. Basal leaf sheaths with papillose-based hairs; cauline blades 1-6 mm wide, flat.
→ 3
3. Spikelets 1.3-1.9 mm long; panicle branches 3-13 cm long; culms 10-80 cm tall
var. filiformis
3. Spikelets 2-2.8 mm long; panicle branches 10-25 cm long; plants 75-150 cm tall
var. villosa
Source FNA vol. 25, p. 364. FNA vol. 25, p. 380.
Parent taxa Poaceae > subfam. Panicoideae > tribe Paniceae > Digitaria Poaceae > subfam. Panicoideae > tribe Paniceae > Digitaria
Sibling taxa
D. abyssinica, D. arenicola, D. bakeri, D. bicornis, D. californica, D. ciliaris, D. cognata, D. didactyla, D. eriantha, D. floridana, D. gracillima, D. hitchcockii, D. horizontalis, D. insularis, D. ischaemum, D. leucocoma, D. longiflora, D. milanjiana, D. nuda, D. patens, D. pauciflora, D. pubiflora, D. sanguinalis, D. serotina, D. setigera, D. simpsonii, D. texana, D. tomentosa, D. velutina, D. violascens
D. abyssinica, D. arenicola, D. bakeri, D. bicornis, D. californica, D. ciliaris, D. cognata, D. didactyla, D. eriantha, D. filiformis, D. floridana, D. gracillima, D. hitchcockii, D. horizontalis, D. insularis, D. ischaemum, D. leucocoma, D. longiflora, D. milanjiana, D. nuda, D. patens, D. pauciflora, D. pubiflora, D. serotina, D. setigera, D. simpsonii, D. texana, D. tomentosa, D. velutina, D. violascens
Subordinate taxa
D. filiformis var. dolichophylla, D. filiformis var. filiformis, D. filiformis var. laeviglumis, D. filiformis var. villosa
Synonyms Syntherisma filiformis Syntherisma sanguinalis
Name authority (L.) Koeler (L.) Scop.
Web links