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, many- seeded berries Extremely poisonous, ripe berries may be less (not) poisonous