Barnyardgrass
This summer annual germinates from seeds from late winter or early spring throughout summer.
Crabgrass
A summer annual, crabgrass has a stiff and papery ligule, with no auricles.
Fall Panicum
An annual grass, fall panicum likes moist land — along streams, ponds and irrigation ditches.
Field Sandbur
This summer annual grassy weed will continue to grow until the first hard frost or freeze occurs in fall.
Giant Foxtail
A clump-forming summer annual, giant foxtail is found especially on fertile soil.
Goosegrass
Found most often in compacted areas, this annual produces seed even when closely mowed.
Johnsongrass
A perennial, this grass reproduces from underground stems and seeds.
Purple Nutsedge
This aggressive perennial has triangular three-sided unbranched flower stems and grass-like leaves.
Quackgrass
A perennial, quackgrass thrives on different soil types and under saline and alkaline conditions.
Texas Panicum
A spreading summer annual, this weed can have an erect growth habit or grow close to the ground.
Wild Proso Millet
This annual seedling resembles volunteer corn but has narrower leaves that are more hairy.
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Bindweed, Field
This perennial spreads from roots and seed. Seed leaves are nearly square with a shallow notch at the tip.
Bindweed, Hedge
Flowers on this perennial have two leafy bracts at the base; leaves are triangular.
Burcucumber
This summer annual's climbing vine resembles cucumber plants in early growth stages.
Cocklebur
A coarse, bushy summer annual, cocklebur invade pastures and other moist areas.
Hemp dogbane
Small flowers appear in dense heads on this perennial, followed later by slender, pointed pods.
Jerusalem artichoke
A perennial with rough branching stems, Jerusalem artichoke is from the sunflower family.
Jimsonweed
This annual prefers to grow in warm areas and is poisonous.
Kochia
The seedlings of this annual have thick, dull green leaves above and magenta ones underneath.
Lambsquarter
This summer annual produces early leaves that are dull bluish green above and often purple below.
Milkweed, Common
The leaves on this perennial can become 4-10 in. long and sometimes have red veins.
Milkweed, Honeyvine
The perennial's slender, twining stems may reach to 10 ft. in length. Leaves are heart-shaped.
Morningglory, Ivyleaf
A summer annual, ivyleaf morningglory has three-lobed leaves and large flowers.
Morningglory, Pitted
This annual's vines have heart-shaped leaves that taper with funnel-shaped white flowers.
Pigweed, Prostrate
An annual, prostrate pigweed tends to spread in multiple directions from a taproot system.
Pigweed, Redroot
A summer annual, this weed has leaves with wavy margins and hairs along the veins of lower surfaces.
Pigweed, Smooth
An annual, smooth pigweed has a pink or red taproot and green to reddish stem.
Prickly Lettuce
An annual or biennial weed, prickly lettuce has prickly leaves with a milky sap.
Puncture Vine
An annual, puncture vine grows on disturbed earth, weedy fields and roadsides.
Ragweed, Common
The leaves on this summer annual are hairy on the upper surface and margin.
Spiny Sowthistle
An annual, spiny sowthistle has bluish-green leaves and stems that produce a milky sap when cut.
Thistle, Canada
A perennial by rhizomes, Canada thistle has hairy young leaves; leaf margins are wavy with spines.