Perennial Broadleaf Weeds

Text adapted from Turfgrass Pest Management Manual: A Guide to Major Turfgrass Pests and Turfgrass
North Carolina Cooperative Extension Service

Perennial broadleaf turf weeds are capable of living more than 2 years. They are primarily spread by seeds, which are produced in the spring or early summer. Many are capable of vegetative reproduction which makes them difficult to control. Dandelion and dock have fleshy taproots. Ground ivy and white clover have creeping stems which root at the nodes. India mockstrawberry has stolons and wild garlic has underground bulbs. These perennial broadleaf turfgrass weeds may be considered as cool-season perennials. Some actively grow during the summer in the western part of the state; for example, dandelion and plantains, while they are less active in the east. They thrive in weak, thin turf, golf fairways and roughs, home lawns, playfields and industrial grounds. White clover may be found under close mowing conditions on golf greens.

Weed Management Practices

Proper turf maintenance is also the key to perennial broadleaf weed control. Maintaining soil phosphorus at medium levels and nitrogen at the proper level for the desired turfgrass reduces the competitive ability of white clover in turf. Development of ground ivy and India mockstrawberry is encouraged by shady, moist areas. Therefore, improving surface drainage, aerating when needed and watering infrequently will help reduce encroachment of these two weeds.
Spray broadleaf weeds with an appropriate postemergence herbicide in March or April depending upon the location within the state. Select the herbicide according to the weeds to be controlled and the tolerance of the turfgrass. For example, bentgrass and hybrid bermudagrasses are less tolerant to 2,4-D than bluegrass, fescue and common bermudagrass. A product containing two or three broadleaf herbicides may need to be selected if several different weeds are present. Some perennial broadleaf weeds may require a second application 4 to 6 weeks after the first. Dandelion and white clover may also be effectively controlled with fall applications. Centipedegrass is sensitive to 2,4-D products. When spraying centipedegrass, reduce the recommended rate for other grasses in half and repeat in 4 weeks for increased safety.

Blackseed Plantain [Plantago rugelli Dene.]

Blackseed plantain is a fibrous-rooted perennial with smooth lower leaves that are oval to elliptical in shape, and purplish at the base of the leaf stalk. Leaf blades are often 1 to 3 inches wide and 3 to 6 inches in length. Leaf margins may be wavy with five prominent veins. The rosette of leaves may lie close to the ground, crowding out desirable grasses. Flowers are arranged along more than half of the stem.

Buckhorn Plantain [Plantago lanceolata L.]

Buckhorn plantain is a very common fibrousrooted perennial weed found in poorly managed turfgrasses. The leaves are basal, long, narrow and pointed with several prominent parallel veins. Flowers are arranged in a dense terminal spike on a long, hairy, leafless stem. As it blooms, the stamens are exerted from the spike.

Broadleaf Dock [Rumex obtusifolius L.]

Broadleaf dock is a taprooted perennial similar to curly dock, but the leaves are broader and may be somewhat oval in outline with a heart-shaped base. They are often 3 to 4 inches wide and 6 to 10 inches long and produced mostly basal. Flowers are produced in clusters at the ends of the stems. They are green, turning reddish-brown at maturity. The three sepals covering the shiny brown seed have toothed edges.

Curly Dock [Rumex crispus L.]

Curly dock is a perennial with a thick taproot. Leaves grow mostly at the base of the plant and are lance-shaped with wavy or curly margins. Leaf blades are 6 to 8 inches long and 1 to 2 inches wide. The green leaves may be tinged with reddish purple. Curly dock seldom produces seed in maintained turf. When the plants grow unchecked, small greenish flowers are produced in clusters at the top of the main stems. Flowers become reddish-brown at maturity. The shiny reddish-brown triangular seed is surrounded by three sepals.

Dichondra [Dichondra repens Michx.]

Dichondra is a perennial; spreading by slender creeping stems that root at the nodes. It forms mats not over 1/2 to 3 inches tall. The kidney-shaped to neatly circular leaves grow alternate to each other, sometimes appearing whirled on the stems. The white to greenish small flowers are borne in clusters in the leaf axils below the level of the leaf. It is cultivated as a ground cover and used in some states.

Dandelion [Taraxacum officinale Wiggers]

Dandelion is a hardy perennial with a thick, fleshy taproot and without a stem. Leaves grow in a rosette from the crown. They are long, narrow, irregularly lobed and lanced shaped. The lobed tips are often opposite each other and pointing towards the crown. Leaves are often purple at the base and emit a milky latex when broken. The deep golden yellow flowers are borne in heads on long hollow stalks. Blossoms soon mature into spherical clusters of whitish fruits, like a white puffball, composed of parachute-like seeds. Seeds are carried by the wind.

Ground Ivy [Glechoma hederacea L.]

Ground ivy is a perennial with creeping stems which root at the node. It forms dense patches and thrives in the sun and shade. The leaves are round, scalloped along the margin, heavily veined and rough on the upper surface. They are borne opposite each other on square-shaped stems. Funnel-shaped blue to violet flowers are found in clusters in leaf axils and occur in the spring.

India Mockstrawberry [Duchesnia indica (Andr.) Focke]

India mockstrawberry is a perennial, spreading by hairy stolons (runners). Leaves are alternate and trifoliate. Leaflets are toothed, hairy, with long hairy petioles with leaf-like stipules. Single flowers with five yellow petals are borne on long stalks from the leaf axils. The fruit is red and fleshy and similar in appearance to the commercial strawberry though smaller and tasteless.

Mosses (Bryum, Ceratodon, Hypnum, or Polytrichum spp.)

Mosses are branched, thread-like primitive forms of plant life that form a thick green mat at the soil surface. They are very competitive in cool, moist, shaded locations such as the north side of buildings and wooded areas. Low fertility, poorly drained soils, high soil acidity, poor watering practices, soil compaction or a combination of these factors that add up to thin weak, turf favors moss development. Spiking, coring or raking may be necessary for removal prior to chemical treatment.

Virginia Buttonweed [Diodia virginiana L.]

Virginia buttonweed is a herbacious perennial with prostrate or spreading branches. The stems are longitudinally ridged especially below the nodes with hairs along the ridges. The leaves are opposite without petioles and rough along the margins. The leaves are slightly thickened, green on the upper surface and light green on the lower surface with both surfaces smooth and slightly folded. The leaves of Virginia buttonweed often take on a mottled yellow mosaic look. The white flowers sometimes have pink streaks in the center and are borne in the leaf axil. Petals are united into a tube. The fruit, bearing four membranous sepals at the tip, is produced in leaf axils.

White Clover [Trifolium repens L.]

White clover is a perennial with creeping stems rooting at some nodes. Leaves have three leaflets with a long erect petiole that is surrounded at the base by a membranous sheath. Leaves are widely ovate with usually a white crescent-shaped mark near the base of the upper surface of each leaflet. The flowering heads are borne on long stalks arising from the stems and usually above the leaves. The flower cluster may be 1/2 to 1 1/2 inches in diameter. The petals are white or occasionally tinged with pink.

Wild Garlic [Allium vineale L.]

Wild garlic is a perennial plant having an odor of garlic which develops from a basal bulb covered by membranous coat. At maturity the bulb is covered with small yellowish bulbs, flattened on one side which readily split apart. Leaves are hollow and round. The greenish pink to purplish flowers are borne in clusters at the stem tip and are often mixed among small greenish aerial bulblets.

Yellow Woodsorrel, Common [Oxalis dillenii Jacq. ]

Common yellow woodsorrel is a herbaceous perennial supported by a shallow taproot and sometimes has very short stolons. Stems are hairy and 4 to 10 inches tall. Leaves are alternate and divided into three leaflets. The leaflets are heart-shaped and partly folded. Two to nine flowers are formed together with each being bright yellow with five petals about 3/8 inch long. The fruit is a narrow capsule 1/2 to 1 inch long. The supporting stalk bends just below the cap" sure. It blooms primarily during March to April.