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The Virtual WeedPatch
id.html
seedheadID.html
Weed Identification: Seedhead & Flowers
Weed identification using flowers and seedhead characteristics is often
the easiest way to learn for new students. Unfortunately, by the time the
time plants flower and set seed, the ball game is over: they have competed
too long in a crop and yield losses have already occurred.
Proceed through each of the weed species below:
Composite (Compositae) Family
dandelion (Taraxacum officinale) Perennial
common cocklebur (Xanthium strumarium)
Summer annual
Ragweed species-group:
-giant ragweed (Ambrosia tri
-common ragweed (Ambrosia artimeisiifolia) Summer annual
Thistle species-group:
-Canada thistle (Circium arvense) Perennial
-biennial thistles:
--musk thistle
--bull thistle (Circium vulgare) biennial
Dogbane (A ) Family
hemp dogbane
Grass (Graminaceae; Poaceae) Family
quackgrass (Elytrigia repens ) Perennial
barnyardgrass
woolly cupgrass (Eriochloa villosa) summer annual
Foxtail species-group:
-bristly foxtail (Setaria verticillata) summer annual
-green foxtail (Setaria viridis) Summer annual
-giant foxtail (Setaria faberi) Summer annual
-knotroot foxtail (Setaria geniculata) summer annual
-yellow foxtail (Setaria glauca) Summer annual
Panicum species-group:
-fall panicum
-witchgrass
-wild proso millet (Panicum mileaceum) Summer annual
Crabgrass species-group:
-large crabgrass (Digitaria sanguinalis) Summer annual
-smooth crabgrass (Digitaria ischaemum) Summer annual
Sorghum species-group:
-johnsongrass
-shattercane
-sorghum-almum
Lambsquarters (Chenopodiaceae) Family
common lambsquarters (Chenopodium album) Summer annual
Mallow (Malvaceae) Family
velvetleaf (Abutilon theophrasti) Summer annual
Milkweed (Asclepiadaceae) Family
Mustard (Cruciferea) Family
field pennycress (Thlaspi arvense) Winter
annual
shepard's purse (Capsella bursa-pastoris)
Annual/Winter annual
wild mustard (Sinapis arvensis) annual/winter
annual
Nightshade ( ) Family
jimsonweed
Pigweed (Amaranthaceae) Family
pigweed species-group
-redroot pigweed
-smooth pigweed
-Powell pigweed
-spiny pigweed
-tumble pigweed
-tall waterhemp
-common waterhemp
-Palmer amaranth
-prostrate pigweed
Smartweed (Polygoneaceae) Family
Knotweed species-group:
erect knotweed (Polygonum erectum) summer annual
prostrate knotweed (Polygonum aviculare) Summer annual
Smartweed species-group:
-Pennsylvania smartweed (Polygonum pensylvanicum) summer annual
-ladysthumb (Polygonum persicaria) summer annual
