Echinochloa colona
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Overview
Aperçu
Regulation :
Remarques Réglementation:
Regulation Notes:
- Echinochloa colona is listed as a Harmful Organism by Grenada, Paraguay, and The Republic of Korea (USDA-PCIT 2024).
- Echinochloa colonum is listed as a Harmful Organism by Grenada (USDA-PCIT 2024).
Distribution :
Répartition :
Echinochloa colona is native to Old World tropical and subtropical regions, although the exact origin is not known (POWO 2024). The species is now widespread throughout all tropical and subtropical regions of the world and warm regions of Asia, Africa, Australia, Pacific island nations, North, Central and South America, typically at lower elevations from sea level to 2000 m (Rojas-Sandoval and Acevedo-Rodriguez 2014).
Habitat and Crop Association :
Habitat et Cultures Associées :
Echinochloa colona is a common weed found in gardens, pastures, along waterways, lake and pond margins, wetlands and other moist habitats, in disturbed areas, and along roadsides in warm regions worldwide (Barkworth et al. 2003; DiTomaso and Healy 2007; Rojas-Sandoval and Acevedo-Rodriguez 2014; efloras 2024). In agriculture, E. colona is reported as a weed associated with at least 35 crops in more than 60 countries (Holm et al. 1977). E. colona is often found in Oryza sativa L. (rice) fields (Holm et al. 1977; deWet et al. 1983; Barkworth et al. 2003; DiTomaso and Healy 2007).
Economic Use, cultivation area, and Weed Association :
Utilisation économique, zone de culture et association de mauvaises herbes :
Echinochloa colona is a highly palatable fodder for livestock. In tropical and subtropical regions, the mature plants can be cut up to four times during the wet season or in rice fields whole plants of E. colona are removed and the collected plants are fed to livestock (Rojas-Sandoval and Acevedo-Rodriguez 2014). The grain of some forms of E. colona is reportedly cultivated and used for human consumption, as are young seedlings (Simpson and Ogorazaly 2001; Rojas-Sandoval and Acevedo-Rodriguez 2014; PFAF 2024).
Duration of Life Cycle :
Durée du cycle vital:
Annual
Dispersal Unit Type :
Type d’unité de dispersion :
Spikelet, floret, caryopsis
General Information
RENSEIGNEMENTS GÉNÉRAUX
Echinochloa is a genus of 40 – 50 species found in tropical to warm-temperate wet or damp environments. Many of the species tend to intergrade, are highly variable, and can be difficult to distinguish (Barkworth et al. 2003; DiTomaso and Healy 2003; Mohler et al. 2021).
Reproduction in Echinochloa colona is primarily by seed, however, the plants also have the ability to reproduce vegetatively via stem fragments separated from the mother plant that produce adventitious roots when nodes come in contact with soil (Rojas-Sandoval and Acevedo-Rodriguez 2014). Seeds are dispersed by wind, water, clinging to animals and farm equipment, and as a seed lot contaminant (Rojas-Sandoval and Acevedo-Rodriguez 2014; USDA-ARS 2024). E. colona plants can produce up to 42,000 seeds with a potential to remain viable for about 3 years in waterlogged conditions (Raju and Reddy 1989).
Herbicide resistance has been reported in some populations of E. colona in all Central American countries, Colombia, Venezula, Australia (Rojas-Sandoval and Acevedo-Rodriguez 2014).
.Identification
Identification
-
Spikelet
Size
- Spikelet length*: 2.3 – 3.2 mm (average 2.7 mm); width 1.1 – 2.0 mm (average 1.6 mm).
- Lower (1st) glume length*: 1 – 1.7 mm (average 1.3 mm). Lower glume about one-third to one-half the length of the spikelet.
- Upper (2nd) glume length*: 2.3 – 3.2 mm (average 2.7 mm); width 1.1 – 2.0 mm (average 1.6 mm). Upper glume about equal to length of spikelet.
*Note: minimum and maximum based on a random selection of 20 spikelets in normal range of this species using image measurement protocol (ISMA 2020). CDA-S-22847, CDA-S-22851. Measured by D.J. Lionakis Meyer.
- Spikelet measurements from the literature:
• Spikelet length: 2.0 – 3.0 mm; width: 1.2 – 1.8 (Costea and Tardif 2002).
• Spikelet length: 2.0 – 3.0 mm; width: 1.0 – 1.5 mm (Barkworth et al. 2003; Waters 2011; eFloras 2024).
• Spikelet length: 2.5 – 2.9 mm; width: 1.4 – 1.6 mm (Bojňanský and Fargašová 2007; note incorrectly labeled as ‘floret’ in the text).
Shape
- Spikelet oval, egg-shaped, or nearly round; dorsoventrally compressed, dorsal side arched and ventral side flat (plano-convex, D-shaped in lateral view).
- Lower (1st) glume broadly triangular, the outer corners wrapping around the base of the upper glume.
- Upper (2nd) glume egg-shaped, tipped with a short, sharp point.
Surface Texture
- The glumes thin papery, surface usually covered with soft short hairs.
- Lower (1st) glume 3 or 5-nerved, upper (2nd) glume 5-nerved (Costea and Tardif 2002).
- Nerves of upper (2nd) glume typically with stiff hairs, up to 1 mm long (Costea and Tardif 2002), the hairs usually do not have swollen bases.
- Glumes unawned.
Colour
- Glumes pale green to brownish yellow coloured, sometimes purple tinged.
Other Features
- The spikelet consists of a pair of glumes, one sterile floret, and one fertile floret.
- Disarticulation occurs below the glumes; the spikelet falls as a unit from the plant
Echinochloa colona (jungle rice) spikelet, floret, and caryopsis
-
Sterile (lower) floret
Size
- Sterile lemma length*: 2.2 – 3.2 mm (average 2.6 mm). Sterile lemma nearly equal to length of spikelet.
- Sterile palea nearly equal in length to lemma.
*Note: minimum and maximum based on a random selection of 20 sterile lemmas in normal range of this species using image measurement protocol (ISMA 2020). CDA-S-22847, CDA-S-22851. Measured by D.J. Lionakis Meyer.
Shape
- Sterile lemma egg-shaped, apex tapered to a slight point.
- Sterile palea oblong to oval, 2-keeled.
Surface Texture
- Sterile lemma texture similar to upper glume, thin papery.
- Sterile lemma 7-nerved (Costea and Tardif 2002),
- Surface of sterile lemma usually covered with soft short hairs, hairs on nerves typically short and stiff, up to 1 mm long (Costea and Tardif 2002), the hairs usually do not have swollen bases.
- Sterile palea membranous, keels with short fine hairs.
Colour
- Sterile lemma pale green to brownish yellow coloured, sometimes purple tinged.
- Sterile palea whitish, translucent.
Other Features
- Sterile lemma unawned.
- Lower floret usually sterile, occasionally staminate (Barkworth et al. 2003).
Echinochloa colona (jungle rice) spikelet in 1st glume and sterile floret view. Scale in mm.
-
Floret (fertile)
Size
- Fertile lemma length*: 2.0 – 2.6 mm (average 2.3 mm); width 1.1 – 2.0 mm (average 1.4 mm).
- Palea nearly equal in length to lemma.
*Note: minimum and maximum based on a random selection of 20 fertile florets in normal range of this species using image measurement protocol (ISMA 2020). CDA-S-22847, CDA-S-22851. Measured by D.J. Lionakis Meyer.
- Measurements from the literature:
• Fertile lemma length: 2.6 – 2.9 mm (Barkworth et al. 2003).
• Fertile lemma length: 2 – 3 mm (Walters 2011).
• Fertile lemma length: 2.1 – 2.5 mm; width 1.2 – 1.4 mm (Bojňanský and Fargašová 2007; incorrectly labeled as ‘caryopses’ in text).
Shape
- Fertile floret dorsoventrally compressed, dorsal side arched and ventral side flat (plano-convex, D-shaped in lateral view).
- Fertile lemma oval to egg-shaped; margins in-rolled over margin of palea.
- Tip tapered to a broad point, at maturity the tip appears shriveled or laterally pinched.
- Fertile palea flat, oval to egg-shaped.
Surface Texture
- Fertile lemma and palea hardened, glabrous, longitudinally striate.
- Tip of fertile lemma thinner, membranous, and shriveled at maturity
- Fertile lemma 5-nerved.
Colour
- Fertile lemma and palea glossy yellowish-brown to grayish-brown coloured, often dark speckled, nerves may be light yellowish-brown.
Echinochloa colona (jungle rice) florets, palea view
-
Caryopsis
Size
- Caryopsis length: 1.2 – 1.6 mm; width: 1.0 – 1.3 mm (North American specimens, Barkworth et al. 2003; Walters 2011)
- Caryopsis length: (0.7) 0.9 – 1.2 mm; width: 0.7 – 1.1 mm (European specimens, Costea and Tardif 2002).
Shape
- Caryopsis round to egg-shaped, dorsoventrally compressed.
Surface Texture
- Caryopsis surface smooth to wrinkled, longitudinally striate, glabrous.
Colour
- Caryopsis body and embryo area light yellow to whitish in colour.
- Hilum reddish brown.
Other Features
- Hilum nearly round.
Echinochloa colona (jungle rice) spikelet, floret, and caryopsis
-
Embryo
Size
- Embryo three-fifths to four-fifths the length of the caryopsis (North American specimens, Barkworth et al. 2003).
- Embryo two-fifths to one-half the length of the caryopsis (European specimens, Costea and Tardif 2002).
Shape
- Embryo oval.
Endosperm
- Endosperm solid (Terrell 1977).
Other Features
- Embryo in lateral position (Maritn 1946).
Echinochloa colona (jungle rice) spikelet, floret, and caryopsis
Identification Tips
CONSEILS POUR L’IDENTIFICATION
Echinochloa colona is in the Paniceae tribe of Poaceae (Barkworth et al. 2003).
- The natural dispersal unit is a spikelet that has one sterile and one fertile floret.
- The spikelet is egg-shaped or teardrop-shaped in outline and D-shaped in profile view.
- The thin papery glumes are unequal in size.
- The lower (1st) glume is somewhat triangular, wraps around the upper (2nd) glume, and is less than half as long as the spikelet.
- The upper (2nd) glume is as long as the spikelet and may have short or long stiff hairs on the nerves.
- The lemma of the sterile floret looks similar in size and texture to the upper glume.
- The sterile lemma is not awned.
- The palea of the sterile floret is membranous and translucent.
- The lemma and palea of the fertile floret are hard, smooth, and shiny.
- The tip of the fertile lemma appears pinched and withered.

Echinochloa colona (jungle rice) spikelet, floret, and caryopsis










Additional Botany Information
AUTRES RENSEIGNEMENTS BOTANIQUES
Flowers/Inflorescence
- The inflorescence of Echinochloa colona is a panicle, up to 15 cm long, with several simple branches, 1- 3 cm long, pointed upwards, slightly spreading or pressed against the main axis, spaced up to 1 cm apart near the base of the inflorescence and more crowded towards the top (DiTomaso and Healy 2007; Rojas-Sandoval and Acevedo-Rodriguez 2014).
- Spikelets are tightly spaced and arranged in four rows along one side of the branch (DiTomaso and Healy 2007; Rojas-Sandoval and Acevedo-Rodriguez 2014).
- Branch axes are glabrous or sparsely hairy, hairs up to 2.5 mm long and with swollen bases (Barkworth et al. 2003).
Vegetative Features
- Echinochloa colona plants have a shallow, fibrous root system (Rojas-Sandoval and Acevedo-Rodriguez 2014).
- Stems 10 – 70 cm long, clumping or spreading, erect or lying on the ground, often rooting at the lower nodes (Barkworth et al. 2003; Rojas-Sandoval and Acevedo-Rodriguez 2014).
- Lower stem nodes may have appressed hairs; upper nodes are glabrous (Barkworth et al. 2003).
- Leaf sheaths are keeled, without ligules and auricles (Rojas-Sandoval and Acevedo-Rodriguez 2014).
- Collar and auricle regions glabrous (DiTomaso and Healy 2007).
- Leaf blades up to 22 cm long and 8 mm wide, flat, the upper surface is usually glabrous (DiTomaso and Healy 2007).
- The leaf sheaths and blades light green, often with purplish transverse stripes or may lack stripes and are purple tinged (DiTomaso and Healy 2007).
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.
In the genus Echinochloa, most of the important measurable characters overlap somewhat among species (Costea and Tardif 2002). Only the characters considered most useful are described below for separating dispersal units of some similar species from E. colona.
Echinochloa crus-galli (L.) P. Beauv.
[Panicum crus-galli L. (USDA-ARS 2024)
Barnyardgrass (AOSA 2024; Walters 2011; USDA-NRCS 2024)
Barnyard grass (Barkworth et al. 2003; USDA-ARS 2024)
- The glumes and sterile floret lemma of E. crus-galli are papery and the nerves typically have stiff, spike-like hairs, whereas in E. colona the glumes and sterile floret lemma are very thin and papery, covered with short soft hairs, and the hairs along the nerves are long and stiff but not thick and spine-like.
- The sterile floret lemma of E. crus-galli is usually awned, and if present, the awn can be up to 50 mm long. The sterile floret lemma of E. colona is awnless.
- In E. crus-galli fertile lemma, the transition from hard, shiny body to withered tip has a line of tiny hairs marking the transition, whereas the transition area in E. colona lacks the line of hairs.
- The caryopses of E. crus-galli are usually larger (1.2 – 2.4 mm long, 1 – 1.8 mm wide) compared to those of E. colona that are generally smaller in size (1.2 – 1.6 mm long, 1.0 – 1.3 mm wide) (Barkworth et al. 2003).
- The caryopses of E. crus-galli are brownish-red or brownish-grey coloured, whereas the caryopses of E. colona are yellowish or whitish coloured (Costea and Tardif 2002; Barkworth et al. 2003).
Echinochloa esculenta (A. Braun) H. Schol
[Panicum esculentum A. Braun); E. crus-galli (L.) P. Beauv. subsp. utilis (Ohwi & Yabuno) T. Koyama; E. utilis Ohwi & Yabuno (Yabuno 1962; USDA-ARS 2024)]
Japanese barnyard grass (Scholz 1992)
Japanese millet (Wiersema and Léon 1999; Barkworth et al. 2003; USDA-ARS 2024; USDA-NRCS 2024)
- The spikelets of E. esculenta are larger (3 – 4 mm long, 2 – 2.5 mm wide; Barkworth et al. 2003) than those of E. colona (2.3 – 3.2 mm, 1.1 – 2.0 mm wide).
- The spikelets of E. esculenta are usually dark brownish to purplish at maturity (Hoste and Verloove 2022), while those of E. colona are pale green to brownish yellow coloured, and sometimes purple tinged.
- The sterile floret lemma may be awned in E. esculenta, although awned spikelets are rare (Hoste and Verloove 2022), while the sterile lemma in E. colona is unawned.
- The caryopses in E. esculenta are longer (1.2 – 2.3 mm) and brown coloured (Barkworth et al. 2003), whereas the caryopses in E. colona are shorter (1.2 – 1.6 mm; Barkworth et al. 2003) and light yellow to whitish in coloured.
- E. esculenta is a cultivated species believed to have been originally derived from E. crus-galli about 4000 years ago in Japan (Yabuno 1962; deWet et al. 1983). It is used for cereal grain, fodder, and birdseed (deWet et al. 1983; Barkworth et al. 2003).
Echinochloa frumentacea Link
Siberian millet (Barkworth et al. 2003)
White panic (Barkworth et al. 2003)
- Spikelets of E. frumentacea are generally larger (3 – 3.5 mm long; Barkworth et al. 2003) than those of E. colona (usually 3 mm or less; Costea and Tardif 2002; Barkworth et al. 2003; eFloras 2024).
- Although the caryopses of E. frumentacea and E. colona are both yellowish to whitish coloured, caryopses of E. frumentacea are larger (1.7 – 2.2 mm long, 1.6 – 1.8 mm wide; Barkworth et al. 2003) than E. colona (0.9 – 1.6 mm long, 0.7 – 1.3 mm wide; Costea and Tardif 2002; Barkworth et al. 2003).
- E. frumentacea is believed to have been originally derived from E. colona in India, and possibly Africa (Yabuno 1962; deWet et al. 1983; Barkworth et al. 2003). This cultivated species is grown for cereal grain, fodder, beer brewing, and for birdseed (Barkworth et al. 2003).
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Cliquez pour sélectionner les espèces

Echinochloa crus-galli

Echinochloa esculenta

Echinochloa frumentacea
Comparison Window
Fenêtre de comparaison
MAIN SPECIES
ESPÈCES PRINCIPALES
Echinochloa colona

Echinochloa colona
Poaceae
Echinochloa colona (jungle rice) florets, palea view
MAIN SPECIES
ESPÈCES PRINCIPALES
Echinochloa colona

Echinochloa colona
Poaceae
Echinochloa colona (jungle rice) florets, lemma view
MAIN SPECIES
ESPÈCES PRINCIPALES
Echinochloa colona

Echinochloa colona
Poaceae
Echinochloa colona (jungle rice) spikelet, floret, and caryopsis
MAIN SPECIES
ESPÈCES PRINCIPALES
Echinochloa colona

Echinochloa colona
Poaceae
Echinochloa colona (jungle rice) spikelet, floret, and caryopsis
MAIN SPECIES
ESPÈCES PRINCIPALES
Echinochloa colona

Echinochloa colona
Poaceae
Echinochloa colona (jungle rice) spikelet in 2nd glume view. Scale in mm.
MAIN SPECIES
ESPÈCES PRINCIPALES
Echinochloa colona

Echinochloa colona
Poaceae
Echinochloa colona (jungle rice) spikelet in 1st glume and sterile floret view. Scale in mm.
MAIN SPECIES
ESPÈCES PRINCIPALES
Echinochloa colona

Echinochloa colona
Poaceae
Echinochloa colona (jungle rice) fertile floret in palea view. Membranous palea of the sterile floret attached. Scale in mm.
MAIN SPECIES
ESPÈCES PRINCIPALES
Echinochloa colona

Echinochloa colona
Poaceae
Echinochloa colona (jungle rice) fertile floret in lemma view. Scale in mm.
MAIN SPECIES
ESPÈCES PRINCIPALES
Echinochloa colona

Echinochloa colona
Poaceae
Echinochloa colona (jungle rice) caryopsis in embryo view. Scale in mm.
MAIN SPECIES
ESPÈCES PRINCIPALES
Echinochloa colona

Echinochloa colona
Poaceae
Echinochloa colona (jungle rice) caryopsis in hilum view. Scale in mm.
SIMILAR SPECIES
ESPÈCES SEMBLABLES
Echinochloa crus-galli

Echinochloa crus-galli
Poaceae
Echinochloa crus-galli (barnyard grass) florets
SIMILAR SPECIES
ESPÈCES SEMBLABLES
Echinochloa crus-galli

Echinochloa crus-galli
Poaceae
Echinochloa crus-galli (barnyard grass) spikelet, floret, and caryopsis
SIMILAR SPECIES
ESPÈCES SEMBLABLES
Echinochloa crus-galli

Echinochloa crus-galli
Poaceae
Echinochloa crus-galli (barnyard grass) spikelet, floret, and caryopsis
SIMILAR SPECIES
ESPÈCES SEMBLABLES
Echinochloa crus-galli

Echinochloa crus-galli
Poaceae
Echinochloa crus-galli (barnyardgrass) fertile floret in palea view. Note the folded palea tip. Scale in mm.
SIMILAR SPECIES
ESPÈCES SEMBLABLES
Echinochloa crus-galli

Echinochloa crus-galli
Poaceae
Echinochloa crus-galli (barnyard grass) spikelets and partial spikelets showing lemmas
SIMILAR SPECIES
ESPÈCES SEMBLABLES
Echinochloa crus-galli

Echinochloa crus-galli
Poaceae
Echinochloa crus-galli (barnyard grass) spikelet
SIMILAR SPECIES
ESPÈCES SEMBLABLES
Echinochloa crus-galli

Echinochloa crus-galli
Poaceae
Echinochloa crus-galli (barnyard grass) spikelet
SIMILAR SPECIES
ESPÈCES SEMBLABLES
Echinochloa crus-galli

Echinochloa crus-galli
Poaceae
Echinochloa crus-galli (barnyard grass) partial spikelet showing lemma
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Besoin d’aide pour l’identification?
Reference(s)
Référence(s)
Association of Official Seed Analysts (AOSA). 2024. Rules for Testing Seeds, Vol. 3: Uniform Classification of Weed and Crop Seeds. Association of Official Seed Analysts, Wichita, Kansas.
Barkworth, M. E. Capels, K. M., Long, S., and Piep, M. B. 2003. Flora of North America, Vo. 25 Magnoliophyta: Commelinidae (in part): Poaceae, part 2. Oxford University Press.
Bojňanský, V. and Fargašová, A. 2007. Atlas of Seeds and Fruits of Central and East-European Flora: The Carpathian Mountains Region. Springer, Dordrecht, The Netherlands.
Boulos, L. and el-Hadidi, M. N. 1984. The Weed Flora of Egypt. The American University in Cairo Press.
Costea, M. and Tardif, F.J. 2002. Taxonomy of the most common weedy European Echinochloa species (Poaceae: Panicoideae) with special emphasis on characters of the lemma and caryopsis. Sida 20(2):525-548.
de Wet, J.M.J., Prasada Rao, K.E., Mengesha, M.H. and Brink, D. E. 1983. Domestication of sawa millet (Echinochloa colona). Economic Botany 37(3): 283–291 (1983). https://doi.org/10.1007/BF02858883
DiTomaso, J. M. and Healy, E. A. 2007. Weeds of California and Other Western States. Vol. 2: Geraniaceae – Zygophyllaceae. Agriculture and Natural Resources Publication 3488. University of California, Oakland, CA.
eFloras. 2024. Flora of China. Echinochloa colona (L.) Link. http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=242319661 Accessed September 13, 2024.
Holm, L. G., Plucknett, D. L., Pancho, J. B., Herberger, J. P. 1977. The World’s Worst Weeds: Distribution and Biology. The University Press of Hawaii, Honolulu, HI.
Hoste, I. and Verloove, F. 2022. Taxonomy of the weed species of the genus Echinochloa (Poaceae, Paniceae) in Southwestern Europe: Exploring the confused current state of affairs. PhytoKeys 197:1–31. https://phytokeys.pensoft.net/article/79499/
Martin, A. C. 1946. The comparative internal morphology of seeds. The American Midland Naturalist 36(3):513-660.
Mohler, C. L., Teasdale, J. R., and DiTommaso, A. 2021. Manage Weeds on Your Farm: A Guide to Ecological Strategies. Sustainable Agriculture Research & Education Handbook 16. https://www.sare.org/wp-content/uploads/Manage-Weeds-on-Your-Farm.pdf
Plants For A Future (PFAF). 2024. Echinochloa colona (L.) Link. Online database. https://pfaf.org/User/Plant.aspx?LatinName=Echinochloa+colona Accessed September 16, 2024.
Plants of the World Online (POWO). 2024. Facilitated by the Royal Botanic Gardens, Kew. https://www.plantsoftheworldonline.org/ Accessed September 13, 2024.
Raju, R. A., Reddy, M. N. 1989. Control of jungle rice in the Godavari delta. Indian Farming 39(2):30-31.
Rehm, S. (ed.) 1994. Multilingual Dictionary of Agronomic Plants. Springer Science & Business Media.
Rojas‐Sandoval, J. and Acevedo‐Rodríguez, P. 2014. Echinochloa colona (junglerice). CABI Compendium. https://doi.org/10.1079/cabicompendium.20368 Accessed September 16, 2024.
Simpson, B. B. and Ogorazaly, M. C. 2001. Economic Botany: Plants in Our World. 3rd Ed. McGraw-Hill.
Terrell, E. E. 1971. Survey of occurrences of liquid or soft endosperm in grass genera. Bull. Torr. Botan. Club 98(5):264-268.
United States Department of Agriculture-Agricultural Research Service-National Plant Germplasm System (USDA-ARS). 2024. Germplasm Resources Information Network (GRIN Taxonomy). National Germplasm Resources Laboratory, Beltsville, Maryland.
https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomydetail?id=316659 Accessed September 13, 2024.
United States Department of Agriculture-Natural Resource Conservation Service (USDA-NRCS). 2024. The PLANTS Database. National Plant Data Team, Greensboro, NC USA, http://plants.usda.gov Accessed September 23, 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 September 16, 2024.
Walters, D.S. 2011. Identification Tool to Weed Disseminules of California Central Valley Table Grape Production Areas. USDA APHIS PPQ CPHST Identification Technology Program, Fort Collins, CO. http://idtools.org/id/table_grape/weed-tool/ Accessed September 16, 2024.