Agrostis
Family :
Famille :
Poaceae
Synonym(s) :
Synonyme(s) :
Vilfa Adans. (POWO 2024; USDA-ARS 2024)
Agraulus P. Beauv. (POWO 2024; USDA-ARS 2024)
Agrestis Bubani (POWO 2024; USDA-ARS 2024)
Anomalotis Steud. (POWO 2024; USDA-ARS 2024)
Bromidium Nees & Meyen (POWO 2024; USDA-ARS 2024)
Candollea Steud. (POWO 2024; USDA-ARS 2024)
Chaetopogon Janch. (POWO 2024; USDA-ARS 2024)
Chaeturus Link (POWO 2024)
Decandolia T. Bastard (POWO 2024; USDA-ARS 2024)
Didymochaeta Steud. (POWO 2024; USDA-ARS 2024)
Linkagrostis Romero García et al. (POWO 2024; USDA-ARS 2024)
Neoschischkinia Tzvelev (POWO 2024; USDA-ARS 2024)
Notonema Raf. (POWO 2024; USDA-ARS 2024)
Pentatherum Nábelek (POWO 2024; USDA-ARS 2024)
Senisetum Honda (POWO 2024; USDA-ARS 2024)
Trichodium Michx. (POWO 2024; USDA-ARS 2024)
Common Name(s) :
Nom(s) commun(s) :
Bentgrass
(English) (ALA 2024; USDA-NRCS 2024)
Bents (English) (Watson et al. 1992+)
Blowngrass (English) (Watson et al. 1992+)
Agrostis canina florets
Agrostis canina florets
Agrostis canina floret
Agrostis canina spikelet, floret and caryopsis
Agrostis capillaris L. (colonial bentgrass) florets with basally attached awns. Scale in mm.
Agrostis capillaris L. (colonial bentgrass) spikelets. Scale in mm.
Colonial bentgrass (Agrostis capillaris) spikelet
Agrostis gigantea (redtop) florets. Scale in mm.
Agrostis gigantea (redtop) spikelets. Scale in mm.
Agrostis gigantea (redtop) florets
Agrostis gigantea (redtop) caryopses, embryo and hilum views, far right caryopsis with palea attached. Scale in mm.
Rough hair grass (Agrostis scabra) florets
Creeping bentgrass (Agrostis stolonifera) florets
Creeping bentgrass (Agrostis stolonifera) floret
Creeping bentgrass (Agrostis stolonifera) floret
Creeping bentgrass (Agrostis stolonifera) caryopses
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Overview
Aperçu
Regulation :
Remarques Réglementation:
- USA Federal Noxious Weed Seed List
Regulation Notes:
Agrostis clavata Trin., clavate bent, is listed as a Harmful Organism by Honduras (USDA-PCIT 2024).
Agrostis spp. and Agrostis gigantea Roth are classified as noxious weed seeds or undesirable grass species when found as a contaminant in grass seed marketed for lawn or turf purposes in certain US states (Delaware, Maryland, New Hampshire, New Jersey, Pennsylvania, Virginia, and West Virginia) (USDA-AMS 2024a).
Distribution :
Répartition :
Agrostis is a large, widespread genus found on every continent except Antarctica. The native distributions of the 190 species and 18 recognized hybrids of Agrostis (POWO 2024) are as follows:
• 51 species and 6 hybrids are limited in distribution to Asia.
• 30 species are found only in South America.
• 26 species are found only in Africa (8 spp. from Madagascar only).
• 22 species are found only in North America.
• 18 species are limited in distribution to parts of Oceania.
• 15 species and 1 hybrid are endemic to one small island or small island group in the Pacific, Atlantic, or Indian Oceans or the Mediterranean Sea.
• 4 species and 9 hybrids are limited in distribution to Europe.
• 24 species and 2 hybrids are native to two or more continents, 13 of which have spread beyond their native range.
Species with worldwide distribution include Agrostis capillaris, A. canina L., A. gigantea, A. mertensii Trin., A. scabra Willd., and A. stolonifera L. (POWO 2024). Some species have been found in unusual locations. For example, A. capillaris or A. stolonifera, or both have been introduced well outside their native ranges to several remote islands or island groups including Chatham, Crozet, Easter, Kerguelen, Macquarie, Marion-Prince Edward, Marquesas, New Caledonia, South Georgia, and St. Helena (POWO 2024).
Habitat and Crop Association :
Habitat et Cultures Associées :
The genus Agrostis has both annual and perennial species. Annual species are usually found in warmer climates, as in the Mediterranean and Southern Hemisphere, while perennial species grow primarily in temperate regions and on tropical mountains (Barkworth et al. 2007). Many species of Agrostis are narrow habitat specialists and are endemics (Barkworth et al. 2007; POWO 2024).
Agrostis species can be found in grasslands, light woodlands, forest clearings, in moist meadows, marshes, vernal pools, and boggy areas, along lake, river, and stream shores, in agricultural fields, along roadsides, ditch banks, disturbed areas, and occasionally on sand dunes (Barkworth et al. 2007). Some species prefer shade while others prefer open habitats, and most are sensitive to saline soils (Watson et al. 1992+).
Agrostis canina, A. capillaris, A. castellana Boiss. & Reut., A. gigantea, and A. stolonifera have been widely introduced and are considered weedy pests when found in agricultural crops and pasture lands (Watson et al. 1992+; Macfarlane and Williams 2007).
Economic Use, cultivation area, and Weed Association :
Utilisation économique, zone de culture et association de mauvaises herbes :
Agrostis canina, A. capillaris, and A. stolonifera are used extensively as lawn and turf grasses. A. stolonifera, A. capillaris, and A. gigantea are also grown for fodder (Watson et al. 1992+; Alderson and Sharp 1995).
Duration of Life Cycle :
Durée du cycle vital:
Annual or perennial
Dispersal Unit Type :
Type d’unité de dispersion :
Spikelet, floret, caryopsis
Distribution of Agrostis L. spp. in Canada and the United States (source: USDA-NRCS 2025)
Global distribution of Agrostis L. spp. (source: GBIF 2025)
General Information
RENSEIGNEMENTS GÉNÉRAUX
The number of recognized species of Agrostis varies between 150 – 220 depending on reference consulted (Watson et al. 1992+; Barkworth et al. 2007; efloras 2024; POWO 2024). Most species have limited distribution and are rarely found outside their native range.
Agrostis canina, A. capillaris, and A. stolonifera have undergone extensive breeding programs for turf applications. The plants can be mowed very short to form a dense, shallow rooted, fine textured turf that can tolerate a significant amount of foot traffic, making these species suitable for golf course putting greens, tee boxes, and fairways, bowling greens, tennis and croquet courts, as well as for other sports fields and landscape applications (Watson et al. 1992+; Alderson and Sharp 1995; ALA 2024). Agrostis gigantea is sold commercially for erosion control, as a forage, and for overseeding dormant warm season grasses (Alderson and Sharp 1995).
Many species of Agrostis are prolific seed producers. A. hyemalis (Walter) Britton et al. can produce up to 16,000 seeds per plant (Stevens 1932). Some species also reproduce vegetatively forming new plants at nodes of creeping stolons or rhizomes (Alderson and Sharp 1995; DiTomaso and Healy 2007; ALA 2024).
.Identification
Identification
-
Spikelet
Size
- Spikelet length: (0.8) 1.2 – 4 (7) mm (Watson et al. 1992+; Barkworth et al. 2007).
- Lower (1st) glume usually slightly longer than the upper (2nd) glume, sometimes nearly equal in length (Tutin et al. 1980; Barkworth et al. 2007).
Shape
- Spikelets narrowly teardrop shaped (lanceolate), narrowly oblong or narrowly egg-shaped, laterally compressed, pedicellate.
- Glume tips slightly pointed (acute), sharply pointed (acuminate), or bristle tipped (aristate).
- Glumes keeled in some species, rounded across the back in other species.
Surface Texture
- Glumes usually thin and membranous.
- Glumes usually 1-nerved.
- Glume mid-nerve in many species have short stiff hairs.
- Body of glumes usually smooth and glabrous (e.g., A. capillaris, A. stolonifera), while in some species glumes are covered with short hairs (e.g., A densiflora Vasey, A. microphylla Steud.) (Barkworth et al. 2007).
Colour
- Glumes pale brownish yellow, sometimes green to purple tinged, shiny to dull.
Other Features
- Spikelet composed of two glumes that enclose a single floret.
- Spikelet disarticulation usually occurs above the glumes, or sometimes the pedicel will fracture and the entire spikelet will fall as a unit.
Agrostis capillaris L. (colonial bentgrass) spikelets. Scale in mm.
-
Floret
Size
- Lemma length range from the literature: 0.5 – 4 mm (Barkworth et al. 2007). Examples include:
• A. nebulosa Boiss, & Reut.: lemma 0.5 – 0.8 mm long
• A. hyemalis (Walter) Britton et al.: lemma 0.8 – 1.2 mm long
• A. capillaris: lemma 1.2 – 2.5 mm long
• A. scabra: lemma 1.4 – 2 mm long
• A. hendersonii Hitchc.: lemma 2.5 – 4 mm long
• Palea absent or very short to nearly equal to lemma length.
Shape
- Florets narrowly teardrop shaped (lanceolate) to egg-shaped.
- Lemma tip, rounded (obtuse), squared (truncate), tapering to a point (acute), or toothed (Barkworth et al. 2007).
Surface Texture
- Lemma and palea membranous, translucent to transparent, usually glabrous, some species with short stiff or soft hairs on lemma (A. castellana).
- Lemma 3 – 5 nerved, nerves do not converge at lemma tip.
- Palea nerveless or 2-nerved; not keeled or 2-keeled.
- Callus hairs usually present, short to nearly half the length of lemma.
(Watson et al. 1992+; Barkworth et al. 2007).
Colour
- Floret colour white to pale brownish yellow.
Other Features
- Lemma nerves sometimes extending beyond tip of lemma forming 2 – 5 teeth.
- Lemma awn, if present, the length, shape (straight or bent), and attachment point (basal, mid-lemma, apical) will vary depending on the species or may vary within an inflorescence (e.g., A. canina, A. capillaris, A. castellana) (Barkworth et al. 2007).
- Rachilla usually not visible.
Agrostis canina florets
- Lemma length range from the literature: 0.5 – 4 mm (Barkworth et al. 2007). Examples include:
-
Caryopsis
Size
- Caryopsis length: (0.6) 1 – 1.5 (2) mm (Barkworth et al. 2007).
Shape
- Caryopsis usually oval in outline, slightly dorsal-ventrally compressed, usually longitudinally grooved on hilum side.
- Hilum oval.
Surface Texture
- Caryopsis surface smooth to minutely wrinkled.
Colour
- Caryopsis colour reddish-brown to brown.
Other Features
- Hilum located near base of longitudinal groove.
- Style base tissue remnant may remain attached at caryopsis apex.
Agrostis canina spikelet, floret and caryopsis
-
Embryo
Size
- Embryo is about one-quarter to slightly more than one-third the length of the caryopsis.
Shape
- Embryo shape oval.
Endosperm
- Endosperm can be liquid, semi-liquid, soft, semi-solid, or solid depending on the species (Terrell 1971; Barkworth et al. 2007).
Other Features
- Embryo in lateral position (Martin 1946).
- Scutellum margin well defined, slightly depressed.
Agrostis gigantea (redtop) caryopses, embryo and hilum views, far right caryopsis with palea attached. Scale in mm.
Identification Tips
CONSEILS POUR L’IDENTIFICATION
- Spikelets, florets, and caryopses of Agrostis spp. are generally smaller than many other grass genera.
- Glumes are thin and membranous, nearly equal in length, exceeding the length of the floret.
- Lemma and palea very thin and membranous, translucent or nearly transparent.
- With a few exceptions, palea is usually much shorter than the lemma or is absent.
- Rachilla does not extend beyond the base of the floret.
- Lemma awn, when present, may be attached in various locations on the lemma. Use caution when using awn character for species identification.
- Spikelet disarticulates above the glumes.
Agrostis canina spikelet, floret and caryopsis
Additional Botany Information
AUTRES RENSEIGNEMENTS BOTANIQUES
Flowers/Inflorescence
- Inflorescence a panicle, shape may range from dense, narrow and cylindrical to open and diffuse.
- Inflorescence branches usually arranged in whorls around the main axis, usually very thin and flexible, short and erect to very long and spreading.
- Spikelets 1-flowered, pedicellate, pedicel 0.3 – 15 mm long.
- Anthers usually 3; 0.1 – 2 mm long.
- Styles 2, separate to the base, white.
In species with awned lemmas, the shape of the awn and attachment position can vary within an inflorescence. When this happens:
- Awns in the upper portion of the inflorescence tend to be longer, bent (geniculate) and attached at the base or in the lower half of the lemma.
- Awns in in the middle portion of the inflorescence may be shorter, may be straight or bent and attached in the upper half of the lemma.
- Awns in the bottom portion of the inflorescence may be reduced to a short bristle attached at or near the tip of the lemma.
- Not all florets within an inflorescence may have awns.
- Use caution when relying on awn characters for species identification.
Description based on Watson et al. (1992+); Barkworth et al. (2007).
Vegetative Features
- Plants are usually tufted, sometimes rhizomatous or stoloniferous, stems (3) 5 – 100 (120) cm tall, usually erect, sometimes growing horizontally along the ground with upturned tips.
- Leaf sheaths margins open, usually smooth and glabrous, sometimes covered with short stiff hairs, rarely hairy.
- Auricles absent.
- Ligules membranous, 1 – 6 mm long, tip blunt, rounded, or tapered to a point.
- Mature leaf blades flat, folded, or in-rolled, narrow, 0.2 – 10 mm wide, usually smooth and glabrous, upper surface somewhat ridged.
- Root system is fibrous.
Description based on Watson et al. (1992+); Barkworth et al. (2007); DiTomaso and Healy (2007); WFO (2024).
Similar Species
ESPÈCES SEMBLABLES
Similar species are based on a study of seed morphology of various species, and those with similar dispersal units are identified. The study is limited by physical specimen and literature availability at the time of examination, and possibly impacted by the subjectivity of the authors based on their knowledge and experience. Providing similar species information for seed identification is to make users aware of similarities that could possibly result in misidentification.
Selected similar species of Agrostis
Spikelets, florets, and caryopses of Agrostis species can have similar characteristics making them difficult to distinguish to species level. Examination of these structures under 20X magnification or greater will show details that may aid in determining species common in seed trade.
| Agrostis canina | Agrostis capillaris | Agrostis gigantea | Agrostis stolonifera |
| Velvet bent,
Velvet bent grass |
Colonial bentgrass | Redtop | Creeping bentgrass |
| Floret 1 – 1.6 mm long; 0.3 – 0.5 mm wide* | Floret 1.3 – 1.9 mm long; 0.4 – 0.5 mm wide* | Floret 1.8 – 2.3 mm long; 0.4 – 0.5 mm wide* | Floret 1.5 – 1.9 mm long; 0.4 – 0.6 mm wide* |
| Lemma whitish to light brownish yellow coloured, dull
|
Lemma light greyish coloured, dull to shiny | Lemma light to dark gold coloured, shiny | Lemma light to dark gold coloured, sometimes silvery, shiny‡ |
| Lemma 5-nerved, nerves with short stiff hairs‡ | Lemma 3 (5)-nerved † | Lemma 3 – 5 nerved, prominent or obscure† | Lemma 5-nerved, obscure or prominent near tip†
|
| Palea absent or about 0.2 mm† | Palea 0.6 – 0.8 mm long*
Palea usually shorter than caryopsis, tip V-notched, rounded, or truncate‡ |
Palea 0.8 – 1.5 mm long*
Palea 2-nerved; tip truncate to shallowly V-notched‡ |
Palea 0.7 – 1.4 mm long†
Palea wide and shoulder-like near apex and tapering abruptly to a minutely notched or rounded tip‡ |
| Callus hairs short, up to 0.1 mm long† | Callus glabrous or with hairs up to 0.3 mm long* | Callus hairs sparse, up to 0.5 mm long† | Callus hairs to 0.5 mm long† |
| Awn up to 5 mm long, attached in lower half of lemma, bent (geniculate), rarely without awn, awned and unawned lemmas may be mixed within a panicle† | Awn rare. When present, length 1.9 – 3.1 mm*, straight or bent (geniculate), attached in lower half of lemma | Awn usually unawned, rarely with straight awn 0.4- 1.5 (3) mm long, attached near the lemma base to near the apex† | Awn usually unawned, rarely with straight, subapical awn, up to 1 mm long† |
| Caryopsis 0.7 – 1.1 mm long; 0.3 – 0.5 mm wide*
Endosperm soft‡ |
Caryopsis 0.8 – 1.1 mm long; 0.3 – 0.4 mm wide*
Endosperm soft‡ |
Caryopsis 0.9 – 1.3 mm long; 0.4 – 0.5 mm wide*
Endosperm solid‡ |
Caryopsis 0.8 – 1.3 mm long; 0.3 – 0.4 mm wide*
Endosperm solid‡ |
*Note: minimum and maximum based on a random selection of spikelets, florets, and caryopses in normal range of this species using image measurement protocol (ISMA 2020).
†Note: measurements from Barkworth et al. 2007.
‡Note: from Musil 1963.
Other similar species
Apera spica-venti (L.) P. Beauv.
Common windgrass
Florets of A. spica-venti are similar in shape to that of Agrostis spp. and the florets are similar in size (1.6 – 3.1 mm long, 0.3 – 0.6 mm wide; Neudorf et al. 2022+). A. spica-venti can be distinguished from most species of Agrostis by the short stiff hairs on the upper one-half to two-thirds or the lemma, the awn attached near the lemma tip can be up to 12 mm long, and the rachilla is thin and wire-like, about 0.5 mm long (Neudorf et al. 2022+).
Gastridium phleoides (Nees & Meyen) C. E. Hubb.
[Gastridium ventricosum auct. non (Gouan) Schinz & Thell.]
Eastern nitgrass
Florets of G. phleoides are similar in size to Agrostis spp. (1 – 1.5 mm long) and the lemma and palea are semi-transparent (Barkworth et al. 2007). G. phleoides can be distinguished from Agrostis by the general floret shape being oval, the lemma is densely pubescent, the palea is nearly as long as the lemma, the rachilla is about one-half the length of palea, and the awn (when present) attached just below the lemma tip is 3 – 6 mm long, straight to slightly bent and longitudinally twisted (Barkworth et al. 2007).
Click to select species
Cliquez pour sélectionner les espèces
Agrostis canina
Agrostis capillaris
Agrostis gigantea
Agrostis scabra
Agrostis stolonifera
Comparison Window
Fenêtre de comparaison
MAIN SPECIES
ESPÈCES PRINCIPALES
Agrostis
Agrostis
Poaceae
Agrostis canina florets
MAIN SPECIES
ESPÈCES PRINCIPALES
Agrostis
Agrostis
Poaceae
Agrostis canina floret
MAIN SPECIES
ESPÈCES PRINCIPALES
Agrostis
Agrostis
Poaceae
Agrostis canina spikelet, floret and caryopsis
MAIN SPECIES
ESPÈCES PRINCIPALES
Agrostis
Agrostis
Poaceae
Agrostis capillaris L. (colonial bentgrass) florets with basally attached awns. Scale in mm.
MAIN SPECIES
ESPÈCES PRINCIPALES
Agrostis
Agrostis
Poaceae
Agrostis capillaris L. (colonial bentgrass) spikelets. Scale in mm.
MAIN SPECIES
ESPÈCES PRINCIPALES
Agrostis
Agrostis
Poaceae
Colonial bentgrass (Agrostis capillaris) spikelet
MAIN SPECIES
ESPÈCES PRINCIPALES
Agrostis
Agrostis
Poaceae
Agrostis gigantea (redtop) florets. Scale in mm.
MAIN SPECIES
ESPÈCES PRINCIPALES
Agrostis
Agrostis
Poaceae
Agrostis gigantea (redtop) spikelets. Scale in mm.
MAIN SPECIES
ESPÈCES PRINCIPALES
Agrostis
Agrostis
Poaceae
Agrostis gigantea (redtop) florets
MAIN SPECIES
ESPÈCES PRINCIPALES
Agrostis
Agrostis
Poaceae
Agrostis gigantea (redtop) caryopses, embryo and hilum views, far right caryopsis with palea attached. Scale in mm.
MAIN SPECIES
ESPÈCES PRINCIPALES
Agrostis
Agrostis
Poaceae
Rough hair grass (Agrostis scabra) florets
MAIN SPECIES
ESPÈCES PRINCIPALES
Agrostis
Agrostis
Poaceae
Creeping bentgrass (Agrostis stolonifera) florets
MAIN SPECIES
ESPÈCES PRINCIPALES
Agrostis
Agrostis
Poaceae
Creeping bentgrass (Agrostis stolonifera) floret
MAIN SPECIES
ESPÈCES PRINCIPALES
Agrostis
Agrostis
Poaceae
Creeping bentgrass (Agrostis stolonifera) floret
MAIN SPECIES
ESPÈCES PRINCIPALES
Agrostis
Agrostis
Poaceae
Creeping bentgrass (Agrostis stolonifera) caryopses
SIMILAR SPECIES
ESPÈCES SEMBLABLES
Agrostis canina
Agrostis canina
Poaceae
Agrostis canina florets
SIMILAR SPECIES
ESPÈCES SEMBLABLES
Agrostis canina
Agrostis canina
Poaceae
Agrostis canina floret
SIMILAR SPECIES
ESPÈCES SEMBLABLES
Agrostis canina
Agrostis canina
Poaceae
Agrostis canina floret
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Reference(s)
Référence(s)
Alderson, J. and Sharp, W. C. 1995. Grass Varieties in the United States. U.S.D.A. Agric. Handbook 170, rev. ed. CRC Press.
Atlas of Living Australia (ALA). 2024. Agrostis L., bentgrasses https://bie.ala.org.au/species/https://id.biodiversity.org.au/node/apni/8414492 Accessed November 11, 2024.
Association of Official Seed Analysts (AOSA). 2024. Rules for Testing Seeds: Volume 3, Uniform Classification of Weed and Crop Seeds. Association of Official Seed Analysts, Wichita, Kansas, USA.
Association of Official Seed Analysts and Society of Commercial Seed Technologists (AOSA/SCST). 2024. Seed Identification List, Version 2.0. Consolidated Exam Committee. https://analyzeseeds.com/committees/consolidated-exam-committee/ Accessed November 11, 2024.
Barkworth, M. E., Capels, K.M., Long, S., and Piep, M. B. (eds.) 2007. Flora of North America, Vol. 24 Magnoliophyta: Commelinidae (in part): Poaceae, part 1. Oxford University Press, New York, NY.
DiTomaso, J. M. and Healy, E. A. 2007. Weeds of California and Other Western States. Volume 2 – Geraniaceae – Zygophyllaceae. Publication 3488. University of California.
International Seed Morphology Association (ISMA). 2020. Method for seed size measurement. Version 1.0. ISMA Publication Guide. https://www.idseed.org/authors/details/method_for_seed_size_meaurement.html
Macfarlane, T. D. and Williams, A. R. 2007. Agrostis castellana (Poaceae) mis-identified as A. capillaris var. aristata in Western Australia. Nuytsia 16(2):472.
Martin, A. C. 1946. The comparative internal morphology of seeds. The American Midland Naturalist 36(3):513-660.
Musil, A. F. 1963. Identification of Crop and Weed Seeds. Agriculture Handbook No. 219. U. S. Department of Agriculture, Agricultural Marketing Service, Washington D.C.
Neudorf, J., Meyer, D. J. L., Salzl, A., Wang, R., Castro, K., Entwistle, K. 2022+. Apera spica-venti (L.) P. Beauv. International Seed Morphology Association. https://seedidguide.idseed.org/fact_sheets/apera-spica-venti/?tab=1 Accessed December 5, 2024.
Plants of the World Online (POWO). 2024. Facilitated by the Royal Botanic Gardens, Kew. http://www.plantsoftheworldonline.org/ Accessed November 11, 2024.
Stevens, O. A. 1932. The number and weight of seeds produced by weeds. Am. J. of Bot. 19:784-794.
Terrell, E. E. 1971. Survey of occurrences of liquid or soft endosperm in grass genera. Bull. Torr. Botan. Club 98(5):264-268.
Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. and Webb, D. A. (eds.). 1980. Flora Europaea, Volume 5: Alismataceae to Orchidaceae (Monocotyledones). Cambridge University Press.
United States Department of Agriculture-Agricultural Marketing Service (USDA-AMS). 2024a. State Noxious-Weed Seed Requirements Recognized in the Administration of the Federal Seed Act. https://www.ams.usda.gov/sites/default/files/media/StateNoxiousWeedsSeedList.pdf Accessed November 11, 2024.
United States Department of Agriculture-Agricultural Marketing Service (USDA-AMS). 2024b. Federal Seed Act Regulations. https://www.ecfr.gov/current/title-7/subtitle-B/chapter-I/subchapter-K/part-201 Accessed November 11, 2024.
United States Department of Agriculture-Agricultural Research Services (USDA-ARS). 2024. Germplasm Resources Information Network (GRIN), https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomysearch Accessed November 11, 2024.
United States Department of Agriculture-Natural Resources Conservation Service (USDA-NRCS). 2024. The PLANTS Database. National Plant Data Team, Greensboro, NC USA. https://plants.usda.gov/home Accessed November 11, 2024.
United States Department of Agriculture-Phytosanitary Certificate Issuance and Tracking System (USDA-PCIT). 2024. https://pcit.aphis.usda.gov/PExD/faces/ViewPExD.jsf Accessed November 11, 2024.
Watson, L., Macfarlane, T. D., and Dallwitz, M. J. 1992+. The grass genera of the world: descriptions, illustrations, identification, and information retrieval; including synonyms, morphology, anatomy, physiology, phytochemistry, cytology, classification, pathogens, world and local distribution, and references. https://www.delta-intkey.com/grass/www/agrostis.htm Accessed November 11, 2024.
Wiersema, J. H. and León, B. 1999. World Economic Plants: A Standard Reference. CRC Press, Boca Raton, FL.
World Flora Online (WFO). 2024. Agrostis L. http://www.worldfloraonline.org/taxon/wfo-4000000996 Accessed November 16, 2024.