HomeWeed Species List

Weed Species List

Below are the species on which we have information. If you would like to search for species by the kind of farming they are an issue in, try our field crop, pasture, vegetable, small fruit, and tree fruit pages. These have a list of useful resources as well as the weeds you are likely to see in those crops.

Grasses

Barnyardgrass (Echinochloa crus-galli)

Barnyard grass, Antonio DiTommaso

Cheat/chess grass (Bromus secalinus)

Leaves of cheatgrass

Crabgrasses (Digitaria spp.)

Large crabgrass. Photo by Antonio DiTommaso.

Fall panicum (Panicum dichtomiflorum)

Fall panicum mature plant on tan brown soil.

Foxtail species (Setaria glauca, S. viridis, and S. faberi)

Giant foxtail. Photo by Antonio DiTommaso of Cornell University.

Italian ryegrass (Lolium multiflorum)

Close up of Italian ryegrass spikelets.

Johnsongrass (Sorghum halepense)

Johnsongrass leaf collar. Photo by Scott Morris of Cornell University.

Orchardgrass (Dactylis glomerata)

Membranous orchardgrass ligule. Photo by Randy Prostack, University of Massachusetts.

Perennial ryegrass (Lolium perenne)

Perennial ryegrass. Photo by Joseph M. DiTomaso of UC-Davis, via Bugwood.org.

Quackgrass (Elytrigia repens)

Quackgrass auricles. Photo by Antonio DiTommaso of Cornell University.

Roughstalk bluegrass (Poa trivialis)

Flower head (panicle type) of roughstalk bluegrass

Switchgrass (Panicum virgatum)

Clump of mature switchgrass plant.

Tall fescue (Schedonorus arundinaceus)

Tall fescue spikelet. Photo by the Ohio State Weed Lab of Ohio State University, via Bugwood.org.

Wirestem muhly (Muhlenbergia fronds)

wirestem muhly. Photo by the Ohio State Weed Laboratory of Ohio State University, via Bugwood.org.

Witchgrass (Panicum capillare)

Witchgrass stem. Photo by Scott Morris of Cornell University.

Woolly cupgrass (Eriochloa villosa)

Woolly cupgrass flowering stem. Photo by Mike Hunter of Cornell Cooperative Extension.

Yellow nutsedge (Cyperus esculentus)

Yellow nutsedge. Photo by Antonio DiTommaso of Cornell University.

Broadleaf Weeds

Bindweeds: Field (Convolvulus arvensis) and hedge (Calystegia sepium)

Hedge vs field bindweed flower identification. Figure from "Weed Identification, Biology and Management", by Alan Watson and Antonio DiTommaso.

Bull thistle (Cirsium vulgare)

Bull thistle flower. Photo by John Cardina of Ohio State University, via Bugwood.org.

Canada goldenrod (Solidago canadensis)

Canada goldenrod. Photo by Charles T. Bryson of USDA Agricultural Research Service via Bugwood.org

Canada thistle (Cirsium arvense)

Fig. 2. Canada thistle seedlings. Photo from "Weed Identification, Biology and Management", by Alan Watson and Antonio DiTommaso.

Common Chickweed (Stellaria media)

Common chickweed flower. Photo by Antonio DiTommaso of Cornell University.

Common lambsquarters (Chenopodium album)

Common lambsquarters. Photo by Antonio DiTommaso of Cornell University.

Common pokeweed (Phytolacca americana)

Common pokeweed. Photo by Antonio DiTommaso of Cornell University.

Common ragweed (Ambrosia artemisiifolia)

Mature common ragweed. Photo courtesy of Cornell Weed Ecology and Management Lab.

Cow parsnip (Heracleum maximum)

Cow parsnip leaf. Photo by Rob Routledge, Sault College, via Bugwood.org

Curly dock (Rumex crispus)

Curly dock. Photo by Antonio DiTommaso.

Dandelion (Taraxacum officinale)

Dandelion flower. Photo by Scott Morris of Cornell University.

Horseweed or marestail (Conyza canadensis)

Horseweed plant. Photo by Antonio DiTommaso of Cornell University.

Field pennycress (Thlaspi arvense)

Field pennycress. Photo by Scott Morris of Cornell University.

Field pepperweed (Lepidium campestre)

Virginia pepperweed flowers and seeds. Photo by the Ohio State University Weed Lab of Ohio State University, via Bugwood.org.

Giant hogweed (Heracleum mantegazzianum)

Giant Hogweed bracts. Photo by Antonio DiTommaso of Cornell University.

Hairy Bittercress (Cardamine hirsuta)

Hairy bittercress. Photo by Scott Morris of Cornell University.

Horsenettle (Solanum carolinense)

Horsenettle. Photo by Antonio DiTommaso of Cornell University.

Japanese Knotweed (Reynoutria japonica)

Japanese knotweed. Photo by Antonio DiTommaso of Cornell University.

Jimsonweed (Datura stramonium)

Jimsonweed plant. Photo by Antonio DiTommaso of Cornell University.

Marsh Yellowcress (Rorippa palustris)

Marsh yellowcress seedpods. Photo by Joseph M. DiTommaso of UC-Davis, via Bugwood.org.

Palmer amaranth (Amaranthus palmeri)

Geometric arrangement of Palmer amaranth leaves.

Poison hemlock (Conium maculatum)

Poison hemlock stem. Photo by Antonio DiTommaso of Cornell University.

Poison Ivy (Toxicodendron radicans)

Poison ivy. Photo by Antonio DiTommaso of Cornell University.

Redroot Pigweed (Amaranthus retroflexus)

Redroot pigweed stem. Photo by Antonio DiTommaso.

Spotted Knapweed (Centaurea maculosa)

Spotted knapweed flower and bract. Photo by Antonio DiTommaso of Cornell University.

Spotted water hemlock (Cicuta maculata)

Spotted waterhemlock. Photo by Karen A. Rawlens, University of Georgia, via Bugwood.org.

Velvetleaf (Abutilon theophrasti)

Velvetleaf seedheads. Photo by Antonio DiTommaso of Cornell University.

Virginia pepperweed (Lepidium virginicum)

Virginia pepperweed flowers Photo by Ohio State Weed Lab of The Ohio State University via Bugwood.org

Wild buckwheat (Polygonum convolvulus)

Wild buckwheat. Photo by Antonio DiTommaso of Cornell University.

Wild carrot (Daucus carota)

Wild carrot. Photo by Antonio DiTommaso of Cornell University.

Wild mustard (Brassica kaber)

Wild mustard. Photo by Antonio DiTommaso of Cornell University.

Wild parsnip (Pastinaca sativa)

Wild parsnip flowers. Photo by John Cardina of the Ohio State University, via Bugwood.org.

Wild radish (Raphanus raphanistrum)

Wild radish flowers Photo by Rebekah D. Wallace of University of Georgia via Bugwood.org

Yellow rocket (Barbarea vulgaris)

Yellow rocket. Photo by Antonio DiTommaso of Cornell University.