Fall 2020 Promo: GET YOUR SMART LAWN PLAN
How to identify lawn weeds. This lawn weed identification guide
includes images, common and scientific names and descriptions to help
you with weed id.
The guide is divided into three weed groups - broadleaf lawn weeds, grass weeds, and grass-like weeds - and then into sub-groups based on the plant's life cycle.
Photos, names and short descriptions are included in this lawn weed identification guide - just follow the links to the individual weed pages where you will find more images, detailed descriptions for and weed control strategies.
Or...use the site search tool below to find weed information.
Simply type the name of the weed and it will return all of the
information found on this site.
A good Integrated Pest Management plan for controlling lawn weeds starts by identifying the problem weed and then learning about its life cycle. When you understand how the weed grows and reproduces, you will be able to decide the best way to manage it.
The presence of certain weeds are indicators of possible
problems with your lawn. For example, prostrate knotweed grows and
thrives in hard, compacted soils. Other weeds indicate your lawn is too
wet, shady, infertile or thin. Identifying weeds and understanding how
they grow will help you correct any problems with your lawn that
encourage weed invasion.
1. Broadleaf Lawn Weeds
Weeds that are not "grass-like" are referred to as broadleaf weeds. Examples include dandelion, clover, and chickweed.
Annual broadleaf weeds - Have a life cycle that lasts only one growing season. From seed germination to flower blooms to seed.
Perennial Broadleaf Weeds - Produce vegetative structures that allow them to live two or more years - roots or stems that survive the winter.
2. Grassy Lawn Weeds
Grasses such as crabgrass, foxtail and
orchard grass, that create an uneven look to lawns and take resources
from the desirable grass.
Black Medic or Yellow Trefoil Medicago lupulina L
is a low growing annual that resembles clover and is often confused
with it. Easily identified by its yellow flowers and leaf arrangement.
Common Mallow Malva neglecta Wallr.
is often found in new lawns and gardens. And can be troublesome in
gardens because it produces a lot of seeds. Its presence indicates
Prostrate Spurge Euphorbia supina Raf. is a low growing summer annual. The leaves have a red blotch in the center and stems ooze a milky sap when broken.
Yellow Wood Sorrel Oxalis stricta
is commonly called Oxalis. Clover-like leaves, and small yellow
flowers. Seed capsules resemble tiny cucumbers. A vigorous grower that
thrives in fertile, warm and moist soils.
Prostrate Knotweed Polygonum aviculare
is tough weed that grows well in heavily trafficked areas with
compacted soils. The branching stems form a dense mat that can be 2 to 3
feet wide. It has blue-green leaves.
Purslane Portulaca oleracea L.
A prostrate growth habit with fleshy stems and leaves. It is a
vigorous grower in moist, warm, well fertilized soils. It can be
persistent in areas that are damp.
Common chickweed Stellaria media L. is a creeping winter annual with tiny star-like white flowers. It germinates in fall or late winter.
Corn Speedwell Veronica arvensis
is a low-growing weed with tiny blue flowers. It commonly invades thin
turfgrass stands, neglected lawns and newly seeded lawns. Corn
speedwell is one of the most prevalent of the weedy Veronica species.
Broadleaf Plantain Plantago major
Broadleaf Plantains can be found in thin lawns that need to be
fertilized. Characterized by rosettes of rounded leaves and short seed
Canada Thistle Cirsium arvense also called Creeping Thistle, is a noxious weed found throughout the United States and Canada.
Mouse-Ear Chickweed Cerastium vulgatum indicates moist, compacted soils. It spreads by creeping stems and has a dense growth habit that forms patches in lawns.
Ground Ivy Glechoma hederacea L. or Creeping Charlie
is an aggressive lawn weed that is difficult to control when
established in lawns. Its creeping stems will root at the nodes, forming
White Clover Trifolium repens L.
competes aggressively with lawns. It used to be considered an important
part of lawn seed mixtures - many people now consider it a weed.
Annual Bluegrass Poa annua is a winter annual that grows vigorously in moist, cool, shaded conditions and tolerates compacted soils.
Smooth Crabgrass Digitaria ischaemum: Crabgrass is a warm-season annual grass, which means it sprouts from seed in late spring and summer and will die when the first hard frost arrives in the fall.
Hairy Crabgrass Digitaria sanguinalis: Crabgrass thrives on moist sites with plenty of sunlight. It will invade areas where your lawn is thinnest and along edges, curbs and sidewalks.
Bermudagrass or Wire grass Cynodon dactylon is a common weed of lawns, gardens, orchards and landscape beds. A very aggressive warm-season, perennial that is tough to control once it becomes established.
Yellow Nutsedge Cyperus esculentus (often called "Nutgrass") gets its name from its yellow/brown seedheads and the tubers or nutlets
that form at the tips of the rhizomes (spreading underground stems).
The triangular stems grow upright and have glossy leaves that are a
light green or yellow-green color and have a very distinct mid-rib.