Transcript Horticulture Crop Weeds

Horticulture Crop Weeds
CS 414
Weed Science Laboratory
Hairy galinsoga
Galinsoga ciliata
Asteraceae
Summer annual, upright, branching
Pubescent stems & leaves (upper surface of
blades)
Opposite leaves with toothed margins
White flowers – both disk and ray flowers
(toothed) present
Common purslane
Portulaca oleracea
Asteraceae
Summer 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
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
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
Cyperus esculentus
Cyperaceae
Yellow nutsedge
Perennial
Tubers are smooth and singular,
yellow seed head, lance-shaped leaf
Cyperus rotundus
Purple nutsedge
Cyperaceae
Perennial
Leaf abruptly tapers to a point,
broader than YNS
Tubers string together along
rhizome
Virginia copperleaf
Acalypha virginica
Euphorbiaceae
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
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
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
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
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
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, manyseeded berries
Extremely poisonous, ripe berries may be less
(not) poisonous