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agrostide stolonifere, carpet bentgrass, creeping bent, creeping bentgrass, fiorin, redtop, spreading bent

colonial bentgrass, Idaho bent, Idaho bentgrass, Idaho redtop

Habit Plants perennial; stoloniferous, stolons 5-100+ cm, rooting at the nodes, often forming a dense mat, without rhizomes. Plants perennial; cespitose, not rhizomatous or stoloniferous.
Culms

(8)15-60 cm, erect from a geniculate base, sometimes rooting at the lower nodes, with (2)4-7 nodes.

8-40 cm, slender, erect, with 2-5 nodes.

Leaves

mostly cauline;

sheaths smooth;

ligules longer than wide, dorsal surfaces usually scabrous, rarely smooth, apices usually rounded, acute to truncate, erose to lacerate, basal ligules 0.7-4 mm, upper ligules 3-7.5 mm;

blades 2-10 cm long, 2-6 mm wide, flat.

mostly basal;

sheaths usually smooth, sometimes scabridulous, not inflated;

ligules (0.7)1-3.8 mm, dorsal surfaces scabridulous, apices rounded to truncate, rarely acute, erose to lacerate;

blades 1-7 cm long, 0.5-2 mm wide, flat, becoming involute.

Panicles

(3)4-20 cm long, less than 1/2 the length of the culm, 0.5-3(6) cm wide, narrowly contracted, dense, oblong to lanceolate, exserted from the sheaths at maturity, lowest node with 1-7 branches;

branches scabrous, ascending to appressed, except briefly spreading during anthesis, usually some branches at each node spikelet-bearing to the base, lower branches 2-6 cm;

pedicels 0.3-3.3 mm.

3-13 cm long, 1-6(8) cm wide, lanceolate to ovate, diffuse, exserted from the upper sheaths at maturity, lowest node with 1-6(10) branches;

branches scabridulous, fairly stiff, more or less ascending, branching at or above midlength, spikelets not crowded, frequently solitary, lower branches 1-4 cm;

pedicels 0.5-6.4 mm.

Spikelets

lanceolate, green and slightly to strongly suffused with purple.

lanceolate to narrowly ovate, purplish.

Glumes

subequal to unequal, 1.6-3 mm, lanceolate, 1-veined, sometimes scabridulous distally, at least on the midvein, acute to acuminate or apiculate;

callus hairs to 0.5 mm, sparse;

lemmas 1.4-2 mm, opaque to translucent, smooth, 5-veined, veins obscure or prominent distally, apices acute to obtuse, entire or the veins excurrent to about 0.1 mm, usually unawned, rarely with a subapical straight awn to about 1 mm;

paleas 0.7-1.4 mm, veins visible;

anthers 3, 0.9-1.4 mm.

subequal, 1.5-2.5 mm, 1-veined, usually scabrous to scabridulous, upper glumes sometimes smooth, apices acute to acuminate;

callus hairs to 0.3 mm, sparse;

lemmas 1.2-2.2 mm, usually smooth, sometimes scabridulous, translucent to opaque, 5-veined, veins usually prominent at least distally, sometimes obscure, apices acute to obtuse, entire, unawned;

paleas absent, or to 0.2 mm and thin;

anthers 3, 0.3-0.6 mm.

Caryopses

0.9-1.3 mm;

endosperm solid.

1-1.3 mm.

2n

= 28, 35,42.

= 28.

Agrostis stolonifera

Agrostis idahoensis

Distribution
from FNA
AK; AL; AR; AZ; CA; CO; CT; DC; DE; FL; 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; OR; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; HI; AB; BC; MB; NB; NL; NS; NT; ON; PE; QC; SK; Greenland
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; AZ; CA; CO; ID; MT; NM; NV; OR; UT; WA; WY; BC
[WildflowerSearch map]
[BONAP county map]
Discussion

Agrostis stolonifera grows in areas that are often temporarily flooded, such as lakesides, marshes, salt marshes, lawns, and damp fields, as well as moist meadows, forest openings, and along streams. It will also colonize disturbed sites such as ditches, clearcuts, and overgrazed pastures. Its North American range extends from the subarctic into Mexico, mostly at low to middle elevations.

Agrostis stolonifera has been confused with A. gigantea (see previous). It is considered to be Eurasian, but some northern salt marsh and lakeside populations may be native. Agrostis stolonifera is also similar to A. castellana (p. 639); it differs in having longer, acute to truncate ligules that are longer than wide, and in possessing extensive stolons. The names A. palustris Huds. and A. maritima Lam. have been applied to plants with longer stolons; all forms intergrade. A hybrid between A. stolonifera and Polypogon monspeliensis, xAgropogon lutosus (p. 668), has been found in the Flora region. It differs from A. stolonifera in having awned glumes and lemmas. Agrostis stolonifera readily hybridizes with A. vinealis (see below), the hybrids being somewhat intermediate between the two parents.

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

Agrostis idahoensis grows in western North America, from British Columbia to California and New Mexico, in alpine and subalpine meadows along wet seepage areas and bogs, and in wet openings with Sphagnum in coniferous forests. It was recently discovered in Chile and Argentina; it is not known whether it is native or introduced there (Rugolo de Agrasar and Molina 1997). Agrostis idahoensis is often confused with A. mertensii (p. 644) and dwarf forms of A. scabra (p. 646), both of which tend to grow in better-drained habitats.

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

Source FNA vol. 24, p. 641. FNA vol. 24, p. 649.
Parent taxa Poaceae > subfam. Pooideae > tribe Poeae > Agrostis Poaceae > subfam. Pooideae > tribe Poeae > Agrostis
Sibling taxa
A. anadyrensis, A. blasdalei, A. canina, A. capillaris, A. castellana, A. clavata, A. densiflora, A. elliottiana, A. exarata, A. gigantea, A. hallii, A. hendersonii, A. hooveri, A. howellii, A. hyemalis, A. idahoensis, A. mertensii, A. microphylla, A. nebulosa, A. oregonensis, A. pallens, A. perennans, A. rossiae, A. scabra, A. tolucensis, A. variabilis, A. vinealis
A. anadyrensis, A. blasdalei, A. canina, A. capillaris, A. castellana, A. clavata, A. densiflora, A. elliottiana, A. exarata, A. gigantea, A. hallii, A. hendersonii, A. hooveri, A. howellii, A. hyemalis, A. mertensii, A. microphylla, A. nebulosa, A. oregonensis, A. pallens, A. perennans, A. rossiae, A. scabra, A. stolonifera, A. tolucensis, A. variabilis, A. vinealis
Synonyms A. stolonifera var. palustris, A. stolonifera var. compacta, A. palustris, A. maritima, A. alba var. stolonifera, A. alba var. palustris, A. alba forma aristigera A. filiculmis, A. tenuis
Name authority L Nash
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