Weed Identification in Pastures, Hayfields, and Sprayfields

This publication is designed to help you identify common weeds found in southeastern North Carolina pastures, hayfields, and sprayfields. It presents descriptions and pictures of some of the most common weeds, and it provides references for other weeds that are not in this publication. Weeds are categorized here as broadleaf, grass, or other, and as warm season or cool season. This publication does not recommend specific chemical control methods because differences in situa- tions, rapidly changing labels, and new products make generalized recommendations impracti- cal. Call your local Extension agent to discuss the best control methods for your farm.

Why Identify Weeds? Cultural control increases the competitive- weed is a plant growing in a place where ness of forage. Fertilizing to improve soil pH and Ayou do not want it to grow. In pastures and fertility maintains grass stands and decreases hayfields, it is impossible to have a “pure” stand weed competition. Once you are sure soil fertility of grass; there will always be plants that volunteer and pH are correct, use the four control methods from the seedbank or from neighboring fields. below in combination to fight weeds. The effec- New volunteer species can mean more and better tiveness of control methods depends on timing. pasture forage, or it can mean losses of forage • Grazing management is one way to control quality and yield. Weeds also have the potential weeds in a pasture situation. This control allows to cause injury or death to livestock if the weed desired plants to become strong and outcompete plants are toxic. Weeds can reduce hay yield and the weeds. Rotational grazing helps to control quality, and they can interfere with hay drying. weeds by giving desired plants the opportunity For these reasons, weed control is very important. to rest and grow undisturbed before being grazed The first step in weed control is identifying again. In rotational grazing systems, animals the weed or weeds you have, which will allow you will often consume weeds they would avoid in to determine whether they need to be controlled. continuous grazing systems. Graze or mow at the Take time to walk through your fields and scout proper height, and do not cut or mow too short. at least 10 to 15 sites in a field. Identify all the • Mechanical control usually involves mow- plants and seedlings at each site. A good time to ing to control weeds. Mowing is usually more assess your fields is between seasons and about effective on broadleaf weeds than grass weeds. 1 week after cutting or grazing. Keep a record of Mowing does have negatives: it increases fuel the weeds you have in each field and when you costs, it may not help with large weeds, and it can start seeing them. This will help you determine spread seeds around, encouraging more weed whether your control program is working. Some growth. If there is no chemical control labeled weeds may take a few years to get under control. for a particular weed or if weeds are too mature, Prevention is any activity that keeps weeds mowing may be your only choice for decreasing from getting into your pasture. Many weeds are competitiveness. Burning, when safe and permit- spread by seeds that are dispersed by hay bales, ted, is another option for control of some weeds plants that reach maturity, livestock movements, in some forages. mowing equipment, wind, water, and wildlife. • Biological control involves the use of natu- Weeds can also be introduced when you plant ral agents such as plants, herbivores, insects, grass seeds that are contaminated with weed and nematodes to suppress weeds. Biological seeds. When you buy seed, make sure you are control is a relatively new area, but progress is getting the best seed for your money. This is why being made in developing and refining biological certified seeds are recommended. control methods. Biological control is usually not Weed Identification in Pastures, Hayfields, and Sprayfields complete and may take several years to become sufficiently effective. • Chemical control is the use of herbicides that kill weeds by inhibit- ing the plant growth process. Select an herbicide based on desired forage species, weed species present, cost, and ease of application. It is very important to apply herbicides at the correct time and rate. Consider spot- spraying weeds. The best time to control weeds postemergence with herbicides is when the weeds have germinated, are young, and are actively growing. This time varies according to whether the weeds in question are cool-season weeds or warm-season weeds. Cool-season weeds: The best time Source: Turfgrass Program, University of Georgia to control with herbicides is from October through December. It is also possible to control cool-season weeds and the reproductive structures (fruits, Cotyledon—A leaf of the embryo from February through April. seeds, flowers) in the second year. of a seed plant that, upon germina- Warm-season weeds: The best Blade—The flat portion of the tion, either remains in the seed or time to control with herbicides is from grass leaf above the sheath. emerges, enlarges, and becomes green. April to mid-July for most species. Bract—A modified or specialized Crown—A region of compressed Always read and follow herbicide leaf. stem tissue from which new shoots label directions, and pay attention to Broadleaf—Plants with flattened are produced, generally found near any grazing and haying restrictions. leaves; dicots, i.e., plants that possess the surface of the soil. The label is the law! two seedling leaves. Leaves are gener- Cultivar—A word derived from ally wider than they are long and have two words, «cultivated variety,» refer- Plant Glossary netlike veins. They can have either ring to any cultivated variety of a ALS-inhibiting herbicides—A round or square stems, and growth particular plant species. class of herbicides that inhibit synthesis can be upright, prostrate, or vining. Dormancy—A period when of branched amino acids in plants by Broadleaf plants can have a taproot, growth and development is temporar- inhibiting acetolactate synthase (ALS). a bulbous root, or fibrous roots. They ily suspended. Alternate—A type of leaf often have showy flowers. Three key Fibrous roots—A root system arrangement characterized by a single indicators help categorize a plant made up of many threadlike members leaf at each node. almost definitively as a broadleaf, of more or less equal length, as in Annual—A plant that germinates, rather than a grass, rush, or sedge: a most grasses. A fibrous root system flowers, and produces seed in one year. square stem, a nonlinear leaf shape, or serves to anchor the plant. Apex—The tip of a leaf or other a nonfibrous root system. Flower—Reproductive structure of plant part. Bunchgrass—A nonspreading some seed-bearing plants, characteris- Auricle—A clawlike appendage grass that lacks rhizomes and stolons. tically having either specialized male projecting from the collar of the leaf Cladodes—Swollen, water-storing or female organs or both male and in a grass plant. stem segments that are not leaves. female organs, such as stamens and a Awn—A fibrous bristle or beard Collar—A narrow band marking pistil, enclosed in an outer envelope of that is an extension of the midrib of the place where the blade and sheath petals and sepals. This structure usu- the large outer bract. of a grass leaf join. A divided collar is ally has showy or colorful parts. Basal—A new plant arising from divided by the midrib, and a continu- Inflorescence—The flowering the base of the stem. ous collar is not divided by the midrib. part of a grass or broadleaf. Biennial—A plant that generally Cool-season plant—A plant that Keeled—A descriptor for a longi- lives two years, forming the vegetative exhibits optimum growth during tudinal prominence on the back of a structures (roots, leaves) in the first year spring and fall months. structure.

2 Weed Identification in Pastures, Hayfields, and Sprayfields

Lateral—On the side. and act as a protective covering of the Leaf—An extension of a plant’s Broadleaf Plant Structure inner parts in the bud. stem that is primarily the plant’s food- Sheath—The portion of a leaf base making organ in photosynthesis. surrounding the stem of a grass. Can Leaf axil—The location where the be open, closed, or split with overlap- petiole attaches to the stem. ping margins, depending on the spe- Leaflet—One of the segments of cies of grass. a compound leaf. Spike—One type of seedhead Legume—A plant that belongs of grass, at the end of the stem, not to the family Leguminosae (or branched. Fabaceae). Legumes live in a symbi- Sprig—A rhizome or stolon of a otic relationship with bacteria that grass, harvested and transplanted to reside in structures on their roots establish a pasture or hayfield. called nodules. These bacteria are able Stem—The stalk of a plant that to take nitrogen from the air, which Source: Center for Turfgrass Envi- supports a leaf, flower, or fruit. exists in a form that plants cannot ronmental Research and Education, Stolon—An aboveground creep- use, and convert it into compounds NC State University ing stem capable of producing roots that plants can use. and tillers at the nodes. Ligule—A membranelike tis- normally being the first organ to grow. Summer annual—A plant that sue or row of delicate hairs typically It grows downward into the soil and germinates, flowers, and produces seed found in grasses at the junction of the produces lateral secondary roots that in one year and that exhibits optimum leaf sheath and blade. emerge at right angles behind the root growth during summer months. Lobe—A rounded portion of a tip. Sometimes it persists and thickens Surfactant—An additive typically leaf. to form a taproot. used with herbicides. The main types Midvein—The vein in the center Prostrate—A low-growing of surfactants are cationic, anioinic, of a leaf. growth pattern, parallel to and hug- and nonionic. The most commonly Node—A joint in a stem, rhizome, ging the ground. May form new roots used type is nonionic. or stolon. at the nodes. Taproot—A main root that grows Opposite—A type of leaf arrange- Raceme—A type of seedhead straight down from the stem and gives ment in which the leaves grow in pairs consisting of spikelets attached along off small lateral roots. on opposite sides of the stem but at the end of the stem or attached at one Tiller—An emerging grass plant the same height on the stem. point at the end of the stem. shoot. Palmate—Descriptor for veins Rhizome—An underground Translucent—Permitting the pas- that originate from the base of the leaf creeping stem capable of producing sage of light. and radiate out toward the outer edges roots and tillers at the nodes. Trifoliate—Typically consisting of the leaf (in the shape of a palm). Rosette—A plant that has a of three leaflets. Clover is an example Panicle—A type of seedhead with cluster of leaves that grow in a circle of a trifoliate plant. multiple seeding branches around the at ground level. The plant will most Tuber—An underground stem stem. Sometimes roughly triangular likely also have one upright stem form attached to the root system and stor- in shape. in the center of the rosette late in the ing carbohydrates. Parallel—Descriptor for veins growing season. Venation—The appearance of that begin at the base of the leaf and Secondary root—A root arising veins in a leaf; either pinnate, palmate, run lengthwise along the whole leaf. from a primary root. or parallel. Peduncle—A stalk bearing a Sedge—A plant very closely Vernation—The arrangement of flower, flower cluster, or fruit. resembling a grass. Can be distin- an immature leaf in the bud shoot; Perennial—A plant that generally guished from grasses by the solidly either rolled or folded. lives longer than two years. triangular stem section. Warm-season plant—A plant Petiole—The stalk of a leaf that Seedhead—The dry fruit contain- that exhibits optimum growth during attaches the blade to the stem. ing seeds. They can be open-panicle summer months. Pinnate—Descriptor for veins that types, compact spikes, or racemes. Winter annual—A plant that do not appear to begin or end in one Sepal—A modified leaf that is establishes from seed, grows, sets seed, place but rather form a net of veins. part of the outermost of the four and dies in one growing season, begin- Primary root—A root that origi- groups of flower parts. The sepals of a ning with germination in the fall and nates in the seed as part of the embryo, flower are collectively called the calyx dying in the spring or summer.

3 Weed Identification in Pastures, Hayfields, and Sprayfields

Warm-Season Broadleaf Weeds are small, thread-like, numerous, branch tips. It is a rapid-growing and located alternately on the stem. weed with high water use and is very Alligatorweed is a perennial weed Basal stem leaves are usually absent competitive in most situations. that is a mat-forming member of at flowering. The entire plant has a the Amaranth family. It is a serious strong odor and is bitter to the taste Mare’s tail, or horseweed, is an aquatic weed problem in the North and toxic to livestock. annual weed. It is an erect weed that Carolina coastal plain and is becom- can reach 6 feet when mature. Leaves ing a major pest in pastures and row Dogfennel is a perennial weed. will be 3 to 4 inches long at the base crops in low-lying areas. Alligatorweed It can grow more than 6 feet tall. and will taper off toward the top of stems are distinctly jointed and hol- The leaves are divided into very fine, the plant. The mature plant will flower low except at the nodes. The stems are somewhat indistinct segments. The out later in the summer and will have light green in color, with faint darker stems are hairy, especially when white or pink flowers. green parallel lines extending from young, but leaves are always hair- one node to the base of the next. Roots less. The stems are soft and easily Pigweed and amaranth are annual are produced at the nodes. Terrestrial broken when young, but they become weeds. There are approximately 60 infestations produce two types of rhi- very tough and woody as the plant species, with foliage ranging from zomes: purplish, horizontal rhizomes ages. When crushed, the leaves and purple and red to gold. They have an that resemble stems with very short stems have a very distinct odor that is extended period of germination, rapid internodes, and fleshy, white, rootlike slightly sour and musty. growth, and high rates of seed pro- rhizomes. Terrestrial stems usually are duction. They can become resistant pithy or even solid, rather than hollow. Horsenettle is a perennial plant to ALS-inhibiting herbicides if used Leaves are oval to lance-shaped, have from rhizomes with obvious spines on continuously. They have red stems a prominent midrib, and are arranged the leaves. The plant can reach 3 feet and egg-shaped, wavy-margined, opposite along the stem. Small, clover- in height. Leaves are elliptic-oblong alternate leaves and can reach 6½ feet like, white flowers are borne on short to oval, alternate, petioled, 2½ to 4½ in height. Stems and leaves may or stalks attached in the leaf axils near inches long, and covered on both may not be hairy. They have a shallow the end of the stems. Flowering occurs surfaces with hairs. Stems are angled taproot that is often reddish in color. from late April through October. at the nodes, become woody with age, They have small, green, flowers that Reproduction is vegetative by fragmen- and have prickles and hairs. Flowers are not noticeable and that are pro- tation because very few seeds form. occur in clusters and are star-shaped, duced in dense, compact panicles that with five white to violet petals and are approximately ¾ inch wide and Bitter sneezeweed is an upright, a yellow center. The fruit is a berry, from 2 to 8 inches in length. These branching annual weed that reaches green when immature, turning yellow weeds are often confused with lambs- 10 to 20 inches tall. It has a strong and wrinkled with maturity. The plant quarter. Pigweed can be very toxic if taproot and a purple stem. The weed’s is capable of poisoning livestock if eaten in large quantities because of water requirement is low, ideal expo- eaten in sufficient quantity; however, the potential nitrate accumulation. sure is full sun, and it reproduces consumption rarely occurs due to the Spiny amaranth and redroot pigweed by seed. A member of the Sunflower prickly stems and leaves. are the two most common types that family, the plant has two varieties thrive in disturbed soils. that are identical except for the flower Lambsquarter is an annual weed Spiny amaranth has pairs of color: one is completely yellow, and that grows upright, 1 to 4 feet tall, spines at the base of the leaf petiole the other is yellow with a red-brown with many branches. The leaves have and the central stem. The spines of center. The flowers are noticeable in a wavy or coarsely toothed mar- spiny amaranth help to distinguish it the late spring or summer and are gin with a soft gray or white mealy from all other closely related pig- located at the end of each branch. coating on young leaves and on the weed species. Redroot pigweed has Each bloom has about eight cleft ray undersides of mature leaves. The dense, compact terminal panicles and flowers with three lobes, often bend- flowers are unremarkable gray-green relatively tall plants with alternately ing downward at maturity. Leaves in dense clusters in leaf axils and arranged leaves.

4 Weed Identification in Pastures, Hayfields, and Sprayfields

Alligatorweed Bitter sneezeweed

Spiny amaranth

Lambsquarter

Dogfennel Spiny amaranth seedhead

Lambsquarter seedhead

Redroot pigweed Mare’s tail or horseweed

Horsenettle Redroot pigweed seedhead

5 Weed Identification in Pastures, Hayfields, and Sprayfields

Warm-Season Broadleaf Weeds yellow flowers. Showy crotalaria of each leaf petiole. The cotyledons of (continued) can produce fruit pods that are 1 to arrowleaf sida are essentially identical 2 inches in length and take on the to those of prickly sida; however, the Pokeweed is a perennial weed that appearance of an inflated cylindrical first true leaf of arrowleaf sida is widest can grow from 1 to 10 feet tall. It has pod. The fruit turns brown to black above the middle and tapers toward single alternate leaves with points at when mature, and the seeds within the leaf base. the end and crinkled edges. The stems the fruit often become unattached, are often pink or red. The flowers are resulting in a “rattlebox” sound when Woolly mullein is a biennial weed. greenish white, in long clusters at the shaken. Seeds are considered mildly The first year, it produces a rosette; the ends of the stems. The flowers develop toxic and can cause problems if con- next year, it produces a stalk with yel- into dark purple berries. Pokeweed sumed in large quantities. low flowers. It is a hairy plant that can usually grows along fence lines. grow to 6 feet or more in height. It has Sicklepod is an annual weed with small, yellow flowers that are densely Ragweed is an upright annual erect, nearly hairless stems, reach- grouped on a tall stem that protrudes weed with single leaflets that are deeply ing 1 to 6 feet in height. It is a plant from a large rosette of leaves. It prefers lobed, with hairs on the upper and with yellow flowers; long, narrow seed well-lit, disturbed soils, where it can lower surfaces. Leaves can grow to 2 or pods; and multidivided leaves, with appear soon after the ground receives more inches wide. It has a taproot with the terminal pair of leaflets being the light, germinating from long-lived many hairs. Flowers are not noticeable. largest. The fruit is a long pod, and the seeds that persist in the soil seed Ragweed emerges in the spring, often seed is inside. Sicklepod has a taproot. bank. It is intolerant of shade from in cultivated areas, but is also found The leaflets are also photosensitive. other plants and unable to survive till- in pastures and along roadsides and The leaflets fold upward by flexible ing. It also hosts many insects, some ditches. It prefers heavier soils. petioles at night or on cloudy days. of which can be harmful to other The pods are green and turn brown plants. Although individual plants are Showy crotalaria is an annual as the seeds mature. Sicklepod plants easy to remove by hand, populations weed/legume with relatively showy and seeds are potentially toxic. are difficult to eliminate permanently. yellow flowers and distinctive seed- pods. The stout, erect stem reaches 6 Sida species, also known as iron- Warm-Season Grass Weeds feet in height and is green or purplish weed, are erect annual weeds com- in color. Stems become waxy and monly found late in the season. The Bahiagrass is a commonly found somewhat angled with age. Leaves are two main species are prickly sida and perennial grass that spreads by rhi- alternate, approximately 2 to 6 inches arrowleaf sida. Sida species stems grow zomes and is easily recognized by its long, widest at the apex and tapering 8 to 20 inches long. They have yellow characteristic Y-shaped black seed- to the base. Leaves are without hairs flowers with five petals that can be soli- head. This fast-growing invasive grass on the upper surface and covered tary or in clusters. Both species seed- forms a dense, low-growing sod, with with hairs on the lower surface. Once lings have two heart-shaped cotyledons small, narrow leaves. Bahiagrass can mature, it will produce large, bright, and small spines that occur at the base be used as a forage grass.

6 Weed Identification in Pastures, Hayfields, and Sprayfields

Ragweed Pokeweed Woolly mullein

Showy crotalaria Pokeweed fruit

Woolly mullein seedhead

Showy crotalaria flowers

Prickly sida

Bahiagrass Sicklepod

Prickly sida Sicklepod wildflowers Bahiagrass seedhead

7 Weed Identification in Pastures, Hayfields, and Sprayfields

Warm-Season Grass Weeds Broomsedge is also called Virginia by its seedhead, which has hairy (continued) bluestem or broomstraw. Broomsedge spikelets in four rows on three to is a perennial grass that forms clumps. eight alternate branches. It has short, Barnyardgrass is an annual with It often goes unnoticed until it thick rhizomes. Rank seedheads in thick stems that may reach 5 feet in matures into a reddish-brown clump late summer can be infected with an height. Barnyardgrass is one of the of broomlike stems. The plant sends ergot-like fungus, turning them gray few grass weeds in which ligules are up slender stems that can reach 3 to black and sappy. Cattle eating a sig- absent. Leaves are without hairs or feet tall in late summer. The stems nificant amount of the infected seed- auricles. The leaf sheaths are often produce numerous white, windborne heads can develop an illness called tinted red or maroon at the base. seeds. It grows on nutrient-poor soils dallisgrass staggers, which is serious The leaves are smooth and rolled in and is especially tolerant of low pH but not usually fatal. Dallisgrass can the shoot. Leaves range from 4 to and low levels of nitrogen and phos- be used as a forage grass. 20 inches in length and may be 0.2 phorous. In the springtime, the grass to 1.2 inches wide. Leaves have a produces clumps of curly, boot-top- Fall panicum is an annual grass distinct white midvein that becomes tall blades, but the fodder provided is with large, round, smooth sheaths keeled toward the basal portions of short lived. Broomsedge’s ability to that are often bent at the nodes. This the leaf. A few short hairs may occur produce allelopathic chemicals sup- weed may reach 7 feet in height. A at the leaf bases. presses the germination and growth primary identifying characteristic of competitive species. In effect, it is the “zigzagged” growth pattern Broadleaf signalgrass is a spread- makes its own natural weed-killers. it takes on due to bending at the ing annual often found growing nodes. There are hairs on the lower along the ground with tips ascend- Crabgrass is an annual grass with leaf surface. The leaves are rolled in ing. Stems are bent at the nodes, and seedlings that sprout quickly, form- the shoot and are 4 to 20 inches long, the plant may also root at the nodes ing a clump with extensive roots. and auricles are absent. The ligule is that touch the ground. The plant Large crabgrass seedlings are pale a fringe of hairs reaching 0.08 to 0.1 may reach 3 feet in height. The leaf green and covered with coarse hairs. inch in length and is often fused at sheaths and blades are often maroon- It has a membranous ligule and no the base. Leaf blades have an obvious tinged. The leaf blades are 1½ to 6 auricles, with young leaves rolled in midvein and are smooth above but inches long and 0.2 to 0.6 inches the bud. Plants form open clumps up sometimes slightly hairy near the leaf wide; they are wider at the base and to 2 feet tall. Once established, it is tip or leaf base. Nodes along the stem taper toward the tip. Signalgrass has difficult to weed out because it roots are usually swollen and bent in dif- a narrow, membranous ligule 0.02 to at the nodes. Smooth crabgrass can be ferent directions, which contributes 0.04 inches long, fringed with hairs. distinguished from large crabgrass by to the rather unusual growth habit of The roots are fibrous. The seed- its shorter, wider leaf, blackish-brown this weed. It has a fibrous root system heads are racemes, each with two to bract, and lack of hairs. Both are with stems that are capable of root- three «branches.» The spikelets are highly palatable, good-quality forages. ing at the nodes. The seedhead is a somewhat flattened in appearance. wide, spreading panicle that devel- The plant is most identifiable by the Dallisgrass is a perennial grass ops a purplish tint when mature. short, wide leaves, rooting nodes, often mistaken for crabgrass species. Individual spikelets are yellow and flattened spikelets, and lack of hairs The leaf appearance is very similar to approximately 0.1 inch long by 0.08 on the leaf blades. crabgrass. It can be readily identified inch wide.

8 Weed Identification in Pastures, Hayfields, and Sprayfields

Dallisgrass

Barnyardgrass Broomsedge

Dallisgrass seedhead

Barnyardgrass seedhead

Broomsedge

Fall panicum

Broadleaf signalgrass

Crabgrass

Broadleaf signalgrass seedhead Crabgrass seedhead Fall panicum seedhead

9 Weed Identification in Pastures, Hayfields, and Sprayfields

Foxtail is a name for three differ- rusty red near the base. Panicles are a bur. It has a membranous ligule ent species of annuals. All are very large, loosely branched, purplish, that has little hairs on the top of it similar grasses and can mainly be and hairy. Spikelets occur in pairs and a flattened stem. Field sandbur differentiated when mature. Foxtail is or threes, and each has an obvious is found mostly on sandy soils. It a clump-forming grass with a seed- awn. Seeds are reddish brown and is troublesome mainly because the head that resembles a fox’s tail. Giant nearly ⅛ inch long. The roots are green or brown spiny burs can cause foxtail has characteristic foxtail-like fibrous. Rhizomes are found close discomfort to livestock. The burs are seedheads that droop when mature to the soil surface and are stout with dispersed when they cling to ani- and leaves with many hairs on the purple spots and scales at the nodes. mals, people, clothing, or equipment. upper leaf surface. Giant foxtail is Johnsongrass can be poisonous to The stems may be erect or spreading, generally larger and has a nodding livestock after it becomes wilted are often bent near the base, and are seedhead, unlike the other foxtails. from frost or new growth following a highly branched. They grow from 6 Yellow foxtail has a characteristic drought or cutting. During hot, dry inches to 1½ feet tall and appear flat foxtail-like seedhead that appears weather, johnsongrass can contain in cross-section. The plant’s leaves yellow when mature; its leaves have enough prussic acid to kill livestock are flat (folded when budding). The long, silky hairs at the base only. if eaten in any quantity. It can cause leaves usually have a raised midvein Green foxtail has a characteristic death from nitrate poisoning. and few or no hairs. The base of foxtail-like seedhead and leaves with each leaf forms a sheath that extends no hairs. Vaseygrass is a medium-large down the stem. The point where the perennial grass. The stems are tufted leaf base joins the sheath is often Goosegrass is an annual grass and grow to 7 feet tall. The leaf blades lighter in color and hairy. The plant that requires moisture and light for are long and narrow, up to 2 feet has a shallow, fibrous root system germination. Goosegrass has a pros- long, and ½ inch wide. The leaves are that emerges from the plant base. It trate growth habit and is often white smooth, with long hairs at the base. reproduces through seed only and in the center with a wagon-wheel-like The sheath is hairy at the base of the competes poorly with other plants. appearance. It does not root at the plant. Vaseygrass has a prominent nodes, but it grows well in compacted membranous ligule. Nutsedge (yellow and purple) soils. Leaf sheaths are flattened, is sometimes incorrectly called nut smooth, and distinctly white to silver Warm-Season Other Weeds grass, but it is a sedge. Sedges can be at the base. Goosegrass has a fibrous distinguished from grasses by the root system. The seedhead is com- Common lespedeza is a mat- stem. Sedges always have a three- posed of two to thirteen spikes each forming, wiry-stemmed, prostrate, sided or triangular stem. Yellow that are 1½ to 6 inches long and 0.1 freely branched annual broadleaf nutsedge is native to North America to 0.3 inch wide, growing in clus- weed. It has dark, green, trifoliate and is a fairly cold-tolerant sedge. ters at the top of stems. Two rows of (arranged in threes) leaves with three Purple nutsedge is a native of India flattened spikelets occur along each oblong, smooth leaflets. The leaflets and is more commonly a problem in spike. Each spikelet contains three to have parallel veins nearly at right warm-season grasses. Both species six light brown to black seeds that are angles to a prominent midvein. The are perennials that produce tubers on 0.04 to 0.08 inch long. Plants often leaves have smooth edges and a short underground rhizomes. The two spe- appear compressed to the soil as if spur at the tip of each leaflet. It also cies can be distinguished by the color they have been repeatedly stepped has a semiwoody taproot and grows of the seedheads and location of the on. The distinctive white center of close to the ground. It flowers in late tubers on the rhizomes. Yellow nut- goosegrass distinguishes it from summer with pink to purple flowers. sedge has a yellowish-tan seedhead, most other grass weeds. Single flowers are found in leaf axils whereas purple nutsedge has a red- on most of the nodes of the main purple seedhead. In yellow nutsedge, Johnsongrass is an aggressive stems. Lespedeza can be used as a the tubers only grow on the ends of perennial grass that spreads by forage crop. rhizomes, while purple nutsedge will rhizomes and seeds. It is a very tall, grow tubers in a chain connected by coarse grass with stout rhizomes. Field sandbur, or sandspur, is rhizomes. Yellow nutsedge has tubers It grows in dense clumps and can an annual weed. Sandburs are a of a chestnut (tan) color, and purple reach 8 feet in height. The leaves are lighter shade of green than most nutsedge has hairy tubers of a char- smooth, 6 to 20 inches long, and other grass weeds. The leaves are coal (black) color. Purple nutsedge is have a prominent white midvein. rough. The roots require careful generally more difficult to control, so The stems are smooth and pink to handling because the seed is actually positive identification is important.

10 Weed Identification in Pastures, Hayfields, and Sprayfields

Johnsongrass

Foxtail Field sandbur or sandspur

Johnsongrass seedhead

Field sandbur or sandspur Foxtail seedheads—giant, green seedheads and yellow

Vaseygrass seedhead

Nutsedge Goosegrass Common lespedeza

Goosegrass seedheads Common lespedeza Nutsedge seedheads

11 Weed Identification in Pastures, Hayfields, and Sprayfields

Warm-Season Other Weeds invade a field or pasture in one grow- Curly dock is a perennial weed. (continued) ing season. Bulbous buttercup can be Curly dock has a deep taproot, a basal distinguished by the bulbous swelling rosette of wavy-margined leaves, and Prickly pear is a low-growing cac- at the base of the stems. Both species an unbranched stem that may reach 5 tus with showy yellow flowers and pads have deeply lobed leaves and produce feet in height. Lower rosette leaves are that have many individual prickles yellow flowers with (usually) 5 petals. petioled, lack hairs, are alternately consisting of tufts of needlelike spines. arranged on the stem, and are dark It is a perennial cactus that is native to Carolina geranium is an annual green with wavy mar­gins. The stem most of the United States. Prickly pear weed that initially forms a basal leaves are arranged alternately along has many pads (called cladodes) with rosette, with subsequent stem elon- the stem and have a membranous tufts of needlelike spines. The prickly gation and branching as the plant sheath that encircles the stem (ocrea) pear has no true leaves present. It has matures. The stems are erect, freely and becomes progressively smaller up a thick rootstock. Pads are able to root branching near the base to grow 28 the flowering stalk. The leaves become and aid in the spread of this species. inches tall. The stems are usually pink reddish-purple with age. As the plant Each pad is a stem that is succulent to red in color and densely hairy. It matures, effective control becomes and thick, containing many individual has divided leaves and distinctive more difficult as the taproot develops. spines. Upon closer examination, it “crane’s bill” fruit. The whitish-pink becomes apparent that some of the to purple flower color of Carolina Dandelion: Carolina false, com- spines (less than ½ inch long) actually geranium helps distinguish it from mon, and cat’s ear are three species consist of many very small “needles” similar geranium species. of dandelion. Carolina false dande- that can very easily stick in skin, cloth- lion is a winter annual or biennial ing, fur, etc. Pads also contain some Chickweed is a low-growing weed, whereas common and cat’s ear spines that are approximately 1 inch annual. The leaves, which range from dandelions are perennials. The hairy long that do not divide in this manner. ½ inch to 1¼ inches in length, are light leaves of Carolina false dandelion are Pads that become detached from the green in color and smooth or possibly deeply lobed and form a basal rosette parent plant have the ability to root hairy toward the base and on the peti- with a taproot. The flower stalk can and form new plants in almost any oles. Common chickweed has oppo- have many branches that end with location. The fruit is a cone-shaped sitely arranged small oval or elliptic flowers, unlike common and cat’s ear capsule that is widest at the top, taper- leaves and stems with rows of hairs. dandelion. Cat’s ear dandelion leaves ing to the base. Individual fruits are Mouseear chickweed is very similar in are densely hairy, and the lobes of the fleshy and grow to approximately 1 to appearance and growth habit, but this leaves are more rounded than other 1½ inches long, turning red to maroon species is densely covered with hairs, dandelions. Common dandelion can with maturity. The flowers are bright unlike common chickweed. be distinguished from cat’s ear dande- yellow in color, 2 to 3 inches wide, and lion because young leaves of common sometimes have a reddish center. Cudweed is an annual or bien- dandelion are hairless. nial weed. In general, the cudweeds Cool-Season Broadleaf Weeds have basal rosettes, and the leaves and Henbit is an annual with square seedheads are covered in distinct, fine, stems and pink-purple flowers, reach- Buttercup is an annual or peren- white, woolly fibers. Some cudweeds ing 16 inches in height. The leaves are nial broadleaf weed. There are two only have this hair on the undersides opposite, reach 5 inches in length, species common to North Carolina. of the leaves; other cudweeds have and are circular to heart-shaped, with Bulbous buttercup is common from this hair on all surfaces. Cudweeds hairs on the upper leaf surfaces and the piedmont east through out the overwinter as small basal rosettes, along the veins of the lower surface. coastal plain while hairy buttercup is but in the spring they usually grow The leaf margins have rounded teeth. predominate from the piedmont west an upright stem. The leaves are egg- The lower leaves occur on petioles, into the mountains. Both are com- shaped, and the plant has a taproot. while the upper leaves are without mon pasture weeds. They are annu- The fruit bears bristly, white, tuftlike petioles (sessile). als which reproduce by seed and can projections that are shed at maturity.

12 Weed Identification in Pastures, Hayfields, and Sprayfields

Curly dock rosette Prickly pear Cudweed

Buttercup, hairy Cudweed seedhead False dandelion

Carolina geranium

Henbit

Common chickweed Henbit Curly dock

13 Weed Identification in Pastures, Hayfields, and Sprayfields

Cool-Season Broadleaf Weeds reaching heights from 6 to 18 inches. Wild mustard is an annual weed (continued) A sheath surrounds the stem like a with characteristic yellow mustard collar until it turns brown and shat- flowers. The cotyledons are kidney- Oldfield toadflax is also known as ters with age. Leaves grow alternately shaped to heart-shaped. The first true common, blue, or purple toadflax. The along the stem. Lower leaves are long leaves are alternate, hairy, and ellip- plant can flower from early spring to and spade-shaped with no lobes. tic in outline, and they have wavy late fall, depending on growing condi- Middle leaves are short and usually margins. It has a taproot in combina- tions. The small blue flowers have three have a lateral lobe near the leaf base. tion with a fibrous root system. The lobes and basal spurs. The leaves are Upper leaves are small with no lobes leaves are alternate and egg-shaped small, bright green, and linear. Small or stalks. Flowers are clustered at the to ovate in outline. The lower leaves clumps of leaves will form in early stem top. Female flowers are greenish, occur as a rosette, are petiolated, spring, and the blue flowers will appear and male flowers are yellow to red. and are unevenly lobed with toothed on long green stems shortly thereafter. margins. Upper leaves become pro- Virginia pepperweed is an annual gressively smaller up the stem, are Plantains: blackseed, broadleaf, weed that develops as a basal rosette not lobed, and either clasp the stem and buckhorn are perennial weeds initially, eventually producing flow- or have short petioles. The stems that reproduce by seeds and roots. ering stems that have a bottle-brush are erect and are branched toward They form a spreading or upright basal appearance. Rosette leaves lack hairs, the top of the plant, and they usu- rosette of narrowly oval leaves that are oval in outline, and are lobed ally have hairs at least at the base of grow above a long, sturdy taproot with along both sides of the leaf. Rosette the plant. The flowers are produced lateral branches. The leaves of buck- leaves do not usually persist once in clusters at the ends of branches. horn plantain are longer and narrower flowering stems are produced. The Individual flowers have four yellow than those of the other plantain spe- stems are erect and branched, and petals and are approximately ¾ inch cies; they are also dark green, are some- they reach 20 inches in height. The wide. The fruit is a dry and elongated times twisted and curled, and grow plant has a taproot. Individual flow- with two valves that fall away, leaving up to 1½ inches wide and 8 inches ers consist of four white or greenish a central partition. long. The inflorescence of buckhorn white petals. The fruits are flattened plantain resembles a bullet. Broadleaf and have a winged structure around Cool-Season Grass Weeds and blackseed plantain can be distin- the exterior. guished by the leaf petioles: blackseed Annual bluegrass (or Poa annua) petioles are usually red-tinged at the Wild garlic and wild onion are is a clump-forming annual grass that base, while broadleaf plantain petioles perennial weeds that grow from tolerates close mowing; otherwise, usually are not. Plantains form many bulbs. Wild garlic tends to persist it may reach 11 inches in height. It small flowers that are tightly clustered later in the growing season than wild is primarily a weed of lawns and at the ends of long stems. onion. Wild garlic sets a flowering turfgrass, but it does grow in pas- stem that can have leaves growing off tures. The leaves are light green. The Red sorrel is a perennial weed. It of it up to half its height, with a veg- leaf blades are ½ inch to 5 inches reproduces by triangular seeds and etative bud (bulbil) in the inflores- long, 0.04 to 0.2 inches wide, and extensive, shallow, horizontal roots. cence instead of flowers. Wild onion folded in the bud; they lack hairs on It has arrow-shaped leaves; a slender, leaves grow from the base of the bulb. either surface. Leaves have a distinc- wiry stem with sheathed nodes; and Wild garlic is often confused with tive boat-shaped tip. The ligule is a red to rust-brown color. Cotyledons wild onion, but the two may be easily slightly pointed and membranous. are oblong and dull green. Seedlings distinguished after a closer exami- Leaf sheaths are somewhat com- resemble a rosette, made up of many nation of the leaf cross-section. The pressed and flattened, without hairs. leaves whose shape changes with age leaves of wild garlic are hollow and The seedhead is an open panicle that from egg- to spade- to arrow-shaped. round, while those of wild onion are is ¾ inch to 2½ inches long. It has a Flowering stems are slender and erect, flatter and more solid. fibrous root system.

14 Weed Identification in Pastures, Hayfields, and Sprayfields

Broadleaf plantain

Wild garlic or onion

Oldfield toadflax Wild garlic

Red sorrel

Buckhorn plantain Wild mustard

Annual bluegrass (Poa annua) Buckhorn plantain seedheads Virginia pepperweed

15 Weed Identification in Pastures, Hayfields, and Sprayfields

Cool-Season Grass Weeds a spike seedhead with seeds alternat- Yellow hop clover is an annual (continued) ing from side to side along the stem. or biennial weed. The leaflets are Italian ryegrass can be distinguished toothed from midblade to tip. It Little barley is a short annual from perennial ryegrass by some can be distinguished by the sessile grass that resembles barley or wheat slight differences: Italian ryegrass has (not stalked) attachment of central when mature. Little barley rarely long, clasping auricles at the nodes, leaflets. It has peduncles that are reaches more than 2 feet in height whereas perennial ryegrass has short, stout, stiff, straight, and often shorter and may occur as a weed of pastures, nonclasping auricles. Perennial rye- than subtending leaves. It has no hayfields, and roadsides. Little barley grass typically has 7 to 9 seeds on the stolon or rhizome; it has upright, stems range from 4 to 24 inches in seedhead, whereas Italian ryegrass hairy, branched stems. The flowers height. It has a bluish-green color. The will have 9 to 15 seeds or more. Also, are bright yellow, with 20 to 30 in stems turn brown in the spring once Italian ryegrass will have an awn on loose clusters on long stalks attached the plant has matured. Leaf sheaths the tips of the seeds, whereas peren- at leaf axils. The flowers turn brown are round and usually do not have nial ryegrass does not. Ryegrass is and fall back when mature. hairs, but they may occasionally have often used for a winter cover crop, hairs present. The sheath also has grazing, or hay. Resources split, overlapping, and translucent North Carolina State University (hyaline) margins. Seedheads consist Other Cool-Season Weeds TurfFiles—www.turffiles.ncsu.edu of flattened spikes that turn tan to Virginia Tech University Weed brown when mature. The seedheads Hairy vetch is an annual or Identification Guide—www.ppws. look like other small-grain seedheads. perennial herb in the pea fam- vt.edu/weedindex.htm Each spikelet contains awns that may ily. It has a climbing stem that can University of Georgia Turf Weed range from 0.08 to 0.5 inch in length. reach 6½ feet. The whole plant has a Management—http://commodities. white-woolly appearance because of caes.uga.edu/turfgrass/georgiaturf/ Ryegrass is a grass that has two its long, soft hairs. It has a shallow WeedMngt/index.html species. There is a perennial rye- taproot system with strong lateral grass, and there are several cultivars branches. It has 10 to 20 purple to Acknowledgments of Italian ryegrass that are annuals. blue flowers. Elongated, flattened Thanks to North Carolina State Italian ryegrass often volunteers from pods contain two to eight rounded University’s Weed Science program seed. Both can be commonly found in seeds ranging in color from dark and Virginia Tech University’s Weed pastures and cultivated areas as well brown to grey-black. Hairy vetch Science program for the use of pic- as roadsides and ditches. Both have grows best in dry, sandy soils. tures and definitions.

16 Weed Identification in Pastures, Hayfields, and Sprayfields

Little barley Yellow hop clover

Hairy vetch

Italian ryegrass seedhead Hairy vetch

17 Weed Identification in Pastures, Hayfields, and Sprayfields

Prepared by

Becky Spearman, Bladen County Livestock Extension Agent Michelle Shooter, Robeson County Livestock Extension Agent Tiffanee Conrad-Acuña, Richmond County Livestock Extension Agent Dan Wells, Harnett County Livestock Extension Agent Randy Wood, Hoke and Scotland Counties Livestock Extension Agent North Carolina Cooperative Extension Service

Published by NORTH CAROLINA COOPERATIVE EXTENSION SERVICE

Distributed in furtherance of the acts of Congress of May 8 and June 30, 1914. North Carolina State University and North Carolina A&T State University commit themselves to positive action to secure equal opportunity regardless of race, color, creed, national origin, religion, sex, age, or disability. In addition, the two Universities welcome all persons without regard to sexual orientation. North Carolina State University, North Carolina A&T State University, U.S. Department of Agriculture, and local governments cooperating.

6/13—VB/BW 13-CALS-3254 AG-764W NC STATE UNIVERSITY

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