Horticulture Crop Weeds

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Horticulture Crop Weeds

• CS 414
• Weed Science Laboratory

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Hairy galinsoga Galinsoga ciliata Asteraceae Summe
r annual, upright, branching Pubescent stems
leaves (upper surface of blades) Opposite leaves
with toothed margins White flowers both disk
and ray flowers (toothed) present
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Common purslane Portulaca oleracea Asteraceae Summ
er annual, prostrate Rounded leaf apex Fleshy
leaf blade Yellow flowers in leaf axils open in
sun Similar in appearance to P. pilosa note
flower color, apex, and leaf shape
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Common Name pink purslane Family Asteraceae
Genus Portulaca Species pilosa  Summer
annual
leaves are thick and fleshy, arranged
alternately on the stem, and have a prostrate
growth habit pointed apex
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Annual sedge Cyperus compressus Cyperaceae Summer
annual Many stems develop in a dense clump Leaf
blades narrow compared to PNS or YNS Flower
spikelets flattened NO tubers or rhizomes
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Cyperus esculentus Cyperaceae Yellow
nutsedge Perennial Tubers are smooth and
singular, yellow seed head, lance-shaped leaf
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Cyperus rotundus Purple nutsedge Cyperaceae Perenn
ial Leaf abruptly tapers to a point, broader than
YNS Tubers string together along rhizome
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Virginia copperleaf Acalypha virginica Euphorbiace
ae Erect, branching summer annual Rounded
cotyledons have notched apex, glabrous First true
leaves opposite, later leaves alternate,
lanceolate Flowers green, in clusters yield a
3-lobed seed pod
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Common Name carpetweed Family Molluginaceae
Genus Mollugo Species verticillata summer
annual
Carpetweed has whorls of leaves at each stem
node in addition to the circular, light green,
mat-like growth
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Common Name large crabgrass Family
Poaceae Genus Digitaria Species
sanguinalis Summer annual

• densely hairy leaf and sheath
• roots at the stem nodes, smooth crabgrass does
  not
• large, jagged membranous ligule

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Common Name goosegrass Family Poaceae Genus
Eleusine Species indica Summer annual

• Flattened stems with a white center
• ligule fringed, uneven, and membranous
• Leaves folded in the bud

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Datura stramonium Jimsonweed Solanaceae Summer
annual Distinct midvein in cotyledons Bur-like
fruit contains many seeds Large white
flowers Leaves with lobed margins Stems become
woody with age All parts extremely poisonous
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Eastern black nightshade Solanum
ptycanthum Solanaceae Erect summer annual Taproot
with lateral branches Hypocotyls covered w/small
hairs Cotyledons green on upper portion of blade,
purple to maroon on lower surface Star shaped
flowers yield small, green, many-seeded
berries Extremely poisonous, ripe berries may be
less (not) poisonous