TF, FF, KB, PR,B, C, SA, Z TF, FF, KB, PR, B, Z

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1 Causal agents, susceptible species, symptoms and conditions that favor several common turfgrass diseases a Disease Causal Agent Susceptible Turfgrasses Symptoms/Conditions Favoring Disease Development Large Brown Patch Dollar Spot Pythium Blight (Cottony Blight, Greasy Spot) Leaf Spot/ Melting Out Fairy Ring Rhizoctonia solani, R. zeae, R. oryzae Sclerotinia homoeocarpa TF, FF, KB, PR,B, C, SA, Z TF, FF, KB, PR, B, C, SA, Z Tall fescue-patches 6" to 3' in Diameter; Smoke ring may be visible, as well as lesions on leaf blades; Favored by hot, humid weather and moderate to high N fertility. Bermudagrass + Zoysia- large patches up to 10' in diameter appear at greenup in spring Patches may be 6" in diameter; Favored by low N fertility; White mycelium is often visible in patches early in morning when dew is present; the pathogen produces no spores Pythium spp. TF, PR, B, C, SA, Z White mycelium may be visible on affected plants; Symptoms follow drainage areas; Plants lose turgidity and totally collapse Drechslera spp., Bipolaris spp. (formerly Helminthosporium spp.) Mushroomproducing fungi/ Basidiomycetes TF, PR, B, C, Z TF, FF, KB, PR, B, C, SA, Z One of the most visible symptoms is a dark brown leaf lesion; These fungi may attack leaves, crowns and roots, causing a generalized thinning, browning and melting out Mushrooms and/or fungal puffballs may be associated with rings of dark green turf, dead turf or normal looking turf Gray Leaf Spot TF, PR Turfgrass plants appear blighted; leaf spots may be present on foliage Red Thread Laetisaria fuciformis TF, FF, KB Patches may resemble dollar Spot; Pinkish-red threads (mycelium) are visible at the tips of leaf blades; Often occurs during spring, late summer and fall Rust Puccinia spp., Uromyces spp. TF, FF, KB, PR, B, Z Normally the first symptom noticed is a

2 Slime Mold Not a true fungus TF, FF, KB, PR,B, C, SA, Z Spring Dead Spot- SDS Ophiosphaerella korrae and others yellowing of affected turf; Close examination of leaf blades reveals yellow leaf spots with yellow to orange pustules of rust; Eventually thinning occurs Many small gray, orange, purple, white or yellow pustules are observed on the leaves of turfgrasses, most often in in small patches; Patches often develop very quickly; Slime mold organisms do not infect turf, but can cause leaves to yellow slightly due to their shading effect; Although unsightly, slime molds are not considered harmful to turf B Bleached patches of dead grass 6"- 3' in diameter appear at greenup; Responsible fungi are active in early Fall, although symptoms only appear the following spring a Sources: Martinez, A. and L. Burpee. Turfgrass diseases: quick reference guide. University of Georgia. C and Windham, A. Turfgrass diseases and their control. University of Tennessee Extension. PB ntrol.pdf and Windham. A. Turf Disease. Red Book. University of Tennessee Extension.

3 A description of several common summer annual grassy weeds Common name Genus species Description Barnyardgrass Echinochloa crusgalli Bunch-type plant with a panicle seedhead, which is often purple in color; The base of the leaf sheath may have a purple color as well; Leaves are rolled in the bud, and do not have a ligule; Often found in areas of the landscape that are poorly drained Crabgrass, smooth Digitaria ischaemum Prostrate growth habit; Leaves and sheaths have no hairs and unlike large crabgrass, stems do not root at the nodes; Seedhead is composed of 2-6 spikes at the top of stems with spikelets in two rows along each spike Crabgrass, large Digitaria sanguinalis Plants grow in clumps; Stems are flat, may appear purplish and are usually branched at the base; Leaves are also flat, and rolled in the bud; Leaves are longer and narrower than those of smooth crabgrass; easily distinguished from smooth crabgrass, long stiff hairs are visible on the sheath and on the upper and lower leaf surfaces Crowfootgrass Dactyloctenium aegyptium Bunch-type plant that roots at the lower nodes; Rolled leaves have hairs along the outer margins near the base and a membranous ligule; Seedhead has spikelets arranged on fingers that radiate outward in the shape of a crow's foot. Grows well in sandy soils Goosegrass Eleusine indica Bunch-type plant that thrives in poorly drained and compacted soils; Stems are flattened and most often originate from a central point forming a mat-like rosette; Leaf blades are smooth and may have sparse hairs near the base; Seedhead has spikelets arranged in rows on fingers and are arranged in a herringbone pattern much like a zipper Foxtail, giant Setaria faberi Bunch-type growth habit; Seedhead is a bristly panicle resembling a fox's tail; Seedheads droop as plants mature; Hairs on the uppermost leaf surfaces set giant foxtail apart from green and yellow foxtails Foxtail, green Setaria viridis Leaf blades often reach 12 in length and 5 mm - 15 mm in width and unlike both giant and yellow foxtails, are hairless or only sparsely hairy; Leaf sheathes are closed and lack hairs except along the margins; The ligule is short and fringed with hairs ~2 mm long Foxtail, yellow Setaria glauca Similar in appearance to giant foxtail except that it has a smaller seedhead that does not droop; Has a hairy ligule and hairs along leaf margins; The seedhead is thicker and has shorter bristles than that of giant foxtail Japanese stiltgrass Microstegium vimineum Well adapted in wet soils and shade; Pale green leaves alternate along a branched stalk and may have

4 a pale strip of hair along the midrib that can be slightly off-centered; Leaf tip is pointed; Stems may turn purplish-red in late summer and fall Stinkgrass Eragrostis cilianensis Bunch-type growth habit; Underside of leaves is glossy; Tufts of pubescence are visible on each side of the sheath at the collar; Foliage emits a distinctive odor when cut A description of several common summer annual broadleaf weeds Common name Genus species Description Black medic Medicago lupulina Leaves are alternate and have three leaflets; Leaflets are wedge shaped and serrated near the tip; Pinnate venation is prominent; Center leaflet is attached to a separate petiole; Bright yellow flowers mature into tightly coiled black seedpods Common lespedeza Kummerowia striata Dark green with trifoliate leaves; Often found growing in dry soils; Several wide spreading branches grow out of a single, semi-woody taproot; Leaves are arranged alternately; Leaflets are elliptical, have smooth margins, and a short spur at the tip; Leaves also have a prominent mid-vein and several parallel veins oriented nearly perpendicular to the mid-vein; Pink to purple flowers bloom in late summer Common purslane Portulaca oleracea Plants reach a height of ~6 and may form mats ~2 or more across; Leaves are oval in outline, smooth, shiny, succulent and may be arranged opposite or alternately on round, reddish stems that radiate out from the center like spokes of a wheel; Flowers are ~3/8 across with 5 yellow petals; One plant is capable of producing more than 200,000 seeds Eclipta Eclipta prostrata Sometimes referred to as False Daisy ; Commonly found growing in moist, open and disturbed sites; Leaves are opposite and lanceolate, with widely spaced teeth along the margins; Stems are thick, succulent and red in color Prostrate knotweed Polygonum aviculare A low-growing plant with dull blue-green leaves arranged alternately, and joined to the stem by a sheathing membrane, or ocrea; Flowers are small and white and are present throughout summer. Prostrate knotweed is often the first summer annual weed to germinate in spring Prostrate spurge Euphorbia supina Leaves are oppositely arranged, small and may have a reddish-brown mark or enlarged spot on the upper surface; Stems of mature plants often appear red and contain a white, milky substance; Flowers are very small and may be pink or white

5 Purslane Portulaca oleracea Leaves are thick, fleshy, and wedge-shaped and arranged alternately on round, purplish-red stems. Yellow flowers bloom from mid-summer to early fall; Prolific seed producer Ragweed Ambrosia artemisiifolia Hairy stems range in color from green to light-pinkishred; Lance-shaped leaves can reach 6 in length and 4" in width, and are usually wider at the base than the tip; Older leaves are relatively hairless, while the underside of young leaves often have hairs; One or more 1-4 cylindrical spikes of small (1/8 long), green flowers form atop erect stems; Flowers later turn yellowish green or brown; Fine, yellow pollen is produced during late summer and early fall A description of several common winter annual weedy grasses Common name Genus species Description Annual bluegrass Poa annua Resembles Kentucky bluegrass however, does not form rhizomes; Leaves have a boat shape tip and often have a wrinkled section near the middle of the blade; Short, open, panicle seedheads are visible each spring Annual ryegrass Lolium multiflorum Upright, bunch-type growth habit; Plants are often purplish-red at the base; Leaves have prominent veins on the upper surface and are glossy on the underside Cheatgrass Bromus tectorum Also referred to as drooping brome since the slender, light-green stems often droop at the tips; Plants have narrow leaves, a fine feathery appearance and may reach 30 in height; When drought stressed, plants may appear purple before turning brown; Sharp spikelets easily cling to clothing; appears on the noxious weeds list of many states Little barley Hordeum pusillum Mature plants can reach a height of ~2 and resemble barley or wheat; Leaf blades are flat, from 2mm 5 mm wide and may be either smooth or rough A description of several common winter annual broadleaf weeds Common name Genus species Description Carolina geranium Geranium carolinianum Leaves have from 5-7 deep lobes; Each lobe is again lobed and bluntly toothed; Flowers range from white to lavender and are suspended 2 or more together on stalks from the upper nodes; Fruits have a conspicuous crane-like beak ~½ long Common chickweed Stellaria media Smooth, oval or elliptic, light green leaves from ½ - 1¼ long are arranged oppositely on prostrate stems; Stems have hairs in vertical rows; Flowers lone or in small clusters at the ends of stems; Flowers, often in clusters, consist of five, lobed white petals

6 Corn speedwell Veronica arvensis Leaves and stems are covered with very soft, fine hairs; Leaves are arranged oppositely on thin, lightgreen, stems that most often branch near the base of the plant; Lower leaves are rounded and toothed; Upper leaves are smaller and pointed; Individual flowers ~1/8 across range in color from blue to blueviolet and have four petal-like lobes Cutleaf evening primrose Oenothera laciniata Plants often grow upright however stems may recline and creep along the soil surface; Leaves are hairy, alternate, toothed and lobed; Yellow flowers at times appear to have a pinkish tinge; Mature plants produce long, curved seed pods Field madder Sherardia arvensis Plants have 4-6 whorled leaves at nodes, square stems and small (3-4 mm long) pinkish to purple flowers that clustered at the end of stems; Leaves are hairy, lanceolate to elliptic in outline and taper to a distinct tip Hairy bittercress Cardamine hirsuta Plants form a rosette of basal leaves ~8" in diameter; Basal leaves are up to 4" long and ¾" wide; Leaves have 5-9 leaflets and a long petiole; A light-green flowering stalk may develop from the center of a rosette; Flowers < ¼ across have four white petals; Eventually, flowers are replaced by light-green to purplish, narrow and cylindrical seedpods up to 1" long Hairy buttercup Ranunculus sardous Plants are hairy and have upright single stems or multiple stems that branch from the base; Stems are hollow; Lobed leaves are alternate and densely hairy on both upper and lower surfaces; Flowers are bright yellow and have five petals Henbit Lamium amplexicaule Plants have square, branched and sparsely hairy stems capable of rooting from lower nodes; Flowers have five lobes, are reddish-purple and are attached in upper leaf axils; Seeds are produced in hard, nutlike fruit (mericarp) Large hop clover Trifolium campestre Plants have hairy, red stems and trifoliate leaves similar to those of white clover (Trifolium repens); Each of the three leaflets has prominent veins and serrated edges from the middle portion of the blade to the tip; Bright yellow flowers are produced in loose clusters Lawn burweed Soliva sessilis Plants have many branches and often produce spinetipped burs in leaf axils; Seed is contained within the hooked burs; Leaves are opposite, sparsely hairy and twice divided into narrow lobes or segments Musk thistle Carduus nutans Also referred to as nodding thistle; Plants form a rosette, are branched and have spiny leaves and

7 stems, ranging from 1½ - 6 tall; Leaves tend to clasp the stem, are deeply lobed, alternate, have a light green mid vein and have very spiny edges; A single, round flower head composed of hundreds of tiny reddish-purple flowers is formed at the ends of stems and may produce ~1,200 seeds Purple deadnettle Lamium purpureum Plants have square stems and pubescent, triangular to heart-shaped leaves that are opposite and may reach 2 long and across; The lower 1/3 rd of each stem of a mature plant often has no leaves; Each pair of leaves is rotated 90 from those directly above or below; Younger leaves appear purple, before becoming dull green as they mature; Upper surfaces of leaves have a network of indented veins, creating a wrinkly appearance; Purple to pinkish-purple flowers form in whorls in the axils of upper leaves; Flowers are slightly hairy outside and have a ring of hairs inside Redstem filaree Erodium cicutarium Plants form a basal rosette with hairy leaves; Individual leaves are arranged on reddish stems directly across from one another and have 3-9 deeply lobed, lance-shaped leaflets; Leaflets range from 1¼ - 8 in length; Flowers with 5 bright pink to purple petals are suspended on relatively long flower stalks (pedicels) and are clustered; Fruit resembles a bird's beak and is ~½ - ¾ long Shepherd s purse Capsella bursapastoris Plants form flat basal rosettes; Rosette leaves are hairy, vary in shape, have edges that are almost smooth or deeply lobed, and may reach 4 in length; Flower stems may be single or branched with sparse, alternate leaves that are reduced in size compared to those of the rosette; Flowers have 4 white to pinkish petals; Flowers are replaced by flat, heart or triangular-shaped pods for which the plant is named Sun spurge Euphorbia helioscopia Like other members of the spurge family, stems exude a milky sap when cut; Leaves are oppositely arranged along the stem, are wider at the apex than the base and have no petioles; Leaves attached to upper stems appear whorled and occur in groups of 2 or 3; Reddish stems may be sparsely hairy; Flowers are inconspicuous and light green to pale yellow in color; Seeds are borne inside 3-parted capsules w/ a single, dark-brown seed per capsule Virginia pepperweed Lepidium virginicum Plants initially form basal rosettes with taproots and lobed leaves; Like shepherd s purse, plants eventually produce flowering stems; Rosette leaves do not usually survive once flowering stems form; Leaves attached directly to the flowering stem are often

8 lance-like in outline; Inconspicuous flowers with 4 greenish white petals are produced at the stem tips in a dense inflorescence giving mature plants a 'bottlebrush' appearance A description of several common perennial grassy weeds Common name Genus species Description Dallisgrass Paspalum dilatatum Coarse-textured plants have a bunch-type growth habit although they do produce short rhizomes; Leaves are hairless except for long white hairs in the collar region; Leaf blades range from ~4-12 long and ~1/5-3/5 wide; Ligules are membranous and tall; Leaf sheaths often turn purplish-red at the base as plants mature; Seedheads have 3-5 finger-like spikes branching from the center; An individual spike is usually 2-4 long and contains 4 rows of spikelets each covered with black silky hairs Nimblewill Muhlenbergia schreberi Plants have stolons, resemble bermudagrass and often form thick, poorly rooted mats in shady or sunny areas of the landscape; Leaf blades are relatively short, ranging from ~¾ - 3 long, and except for a few hairs near the ligule, nearly hairless; The ligule is very short, membranous and has distinctive teeth along the top; At times, leaf sheaths and stems appear purplish-red; Slender, panicle seedheads may reach 6 in length Orchardgrass Dactylis glomerata Plants have a bunch-type growth habit; Blue-green leaf blades have a prominent mid-rib on the underside; The leaf sheath is flattened and the ligule is membranous, long and pointed; The panicle seedhead is green and densely clustered with fanshaped spikelets Quackgrass Agropyron repens Dull, blue- or sliver-green, rhizomatous plant with clasping auricles like those of annual ryegrass (Lolium multiflorum) that often forms mats or patches; Has been shown to be allelopathic- releasing chemicals that inhibit the growth of other plant species; Stems often bend out and up from the base of the plant; Leaves may reach 12 in length and have a longitudinal twist; Ligules are membranous and short; Lower leaf sheath is often hairy, while the upper sheath is most often smooth; Seedhead is a narrow spike ~2-8 long with several individual spikelets arranged in 2 rows along the stem A description of several common perennial broadleaf weeds, rushes and sedges Common name Genus species Description

9 Canada thistle Cirsium arvense Plants produce lobed leaves that are alternately arranged in basal rosettes and have extensive rhizomes; Indentations in leaves creating lobes become triangular as plants mature; Upper leaf surface is darker green than that of the lower leaf surface; Although leaves have very stiff spines, stems are spineless, unlike those of bull thistle (Cirsium vulgare)and musk thistle (Cirsium nutans); Flowers are ~½ in length and width, pink and bristly Chickory Cichorium intybus Plants are erect, produce a taproot and form a basal rosette of lobed leaves; Unlike lobes on dandelion leaves that point toward the center of the rosette, the lobes on chicory leaves point away from the center of the rosette; Leaves on stems are hairy, basal leaves are not; Basal leaves usually die once flowers appear; Flowers range from blue to purple in color; Flowers have florets and are ~1-1½ across Curly dock Rumex crispus Plants have a taproot and initially form a rosette of lance-shaped leaves; Leaves of mature plants are alternate to one another along the stem, hairless, ~6 8 long and have curled or wavy edges; Some leaves may have a purplish-red tinge; Stems are most often unbranched below each flower head Dwarf cinquefoil Potentilla canadensis Plants range from 2-6 tall and often produce stolons up to 20 long; Leaves attached to long petioles have five wedge-shaped leaflets ~1½ in length; Margins of leaflets are toothed from the middle to the tip; Stems are covered with dense silvery hairs; Flowers are ~½ across and have 5 small yellow petals Dandelion Taraxacum officinale Lobed leaves, often purple at the base, emerge from the crown forming a rosette; Leaf lobes point back toward the center of the plant; Single bright yellow flowers suspended atop an upright flower stalk produce a sphere of whitish fruits with brown, parachute-like seeds; Leaves and flower stalks exude a milky white sap when broken Globe sedge Cyperus globulosus Plants have densely tufted triangular stems, short rhizomes and round seedheads comprised of several spikelets; Each spikelet consists of a stalk with a terminal cluster of seeds Green and Falsegreen kyllinga Kyllinga spp. Green (Kyllinga brevifolia) and false-green kyllinga (Kyllinga gracillima) are very similar in appearance, have a strong network of mat-forming rhizomes and produce green, globe-like seedheads ~3/8 in diameter and tan-colored seeds; Seedhead development is day-length dependent such that green

10 kyllinga flowers during all warm months and false green kyllinga only flowers during late summer; Leaves are narrow and range from ~1-5 or more in height; Flower stalks are triangular in cross section and from ~2-8 inches long; A group of 3 leaves radiates out from the flower stalk just below each seedhead; Each of the spikelets within each flower is capable of producing a viable seed; A mature plant may produce >100 flowers and up to 5,000 seeds annually Ground ivy Glechoma hederacea Low-growing, creeping plants have square stems and kidney-shaped leaves with scalloped margins; Stolons may be >3 long; Leaves are arranged opposite from one another along the stem, have a rough upper surface and very prominent veins, and omit a minty scent when crushed or mown; Clusters of up to 3 tubular, blue-to-purple flowers ~½ long develop from leaf axils; The corolla of each flower is narrow at the base and flares outward like a trumpet into spreading lobes; Upper and lower lobes are notched and larger than the 2 side lobes Healall Prunella vulgaris Like ground ivy, healall is a member of the mint family and has square stems; In turfs, plants sprawl and usually form upright flower clusters from leaf axils; Leaves may reach a length of 4, have relatively long petioles, are oblong in outline and are arranged opposite from one another along the stem; Although young stems are covered with stiff hairs, mature stems lack hairs; Plants do not omit an odor when crushed; Roots are shallow, fibrous and form from stem nodes. Flowers have 5 bluish-purple or white petals < ½ long that join together forming a 2-lipped tube; Each tube consists of a rounded upper lip and a 3-lobed lower lip; Fruits are pods containing 4 brown nutlets that are triangular in cross-section Indian mock strawberry Moneywort Duchesnea indica Lysimachia nummularia Plants resembling strawberry spread by way of stolons; The surface of stolons is covered with dense hairs; Leaves ~¾ - 1¾" long and ½ - 1¼ wide have three leaflets with toothed margins; Single yellow flowers are suspended atop long petioles; Each flower is ~¾" across and has 5 yellow petals and 5 green sepals; Plants produce what is referred to as accessory or false fruit in which some of the flesh is derived from exterior tissue adjacent to but not from the ovary Mat-forming plants with smooth, branching and hairless light-green stolons capable of growing up to 2 long; Leaves are oval or coin-shaped in outline,

11 Mouse-ear chickweed Cerastium vulgatum opposite and from ¼ - 1½ long; Single yellow flowers with 5 petals are suspended on pedicels that arise from leaf axils Mat-forming plants spread aggressively by way of hairy stems up to ~20 long that root at the nodes; Although similar in shape to common chickweed (Stellaria media), leaves range from greyish-green to dark-green in color and are densely hairy on the upper surface; Veins on the lower leaf surface are also hairy; Flowers are inconspicuous, produced in clusters and have 5 deeply divided white petals; Cylindrical, capsule-like fruits ~¼ long contain several very small, reddish-brown seeds Nutsedge, purple Cyrerus rotundus Plants are shiny, dark green and spread rapidly, producing chains of rhizomes and tubers; There are often 2-6 or more tubers per chain; Leaves are arranged in sets of 3 from the base, v-shaped in crosssection and have blunt or rounded tips; Flowering stems are triangular in cross-section; Flower heads are a cluster of dark-reddish to purplish-brown spikes arising from a common center; Some spikes are suspended on stalks of unequal length; Plants rarely produce seed in TN Nutsedge, yellow Cyperus esculentus Plants spread by way of rhizomes that produce a single, terminal, tan-to-brown-colored tuber; Mature plants have shiny, light- to medium-green leaves and much longer stems than those of purple nutsedge (Cyperus rotundus); Leaves are thick, stiff, v-shaped in cross-section and arranged in sets of three from the base; Leaf tips are pointed; Flower heads are borne on triangular stems and contain clustered strawcolored to golden brown spikelets with many flowers capable of producing oblong and single-seeded fruits Path rush Juncus tenuis Plants are most often densely tufted and have light to medium green, slender, smooth and unbranched upright or ascending stems; Leaves are located at or near the base of each stem, and ~1 mm wide and up to up to 10 long; Leaf blades are medium green, flat and smooth with slightly rolled margins; A branching inflorescence ~½ - 3 across is suspended atop each flowering stem; Inflorescences have one or more flower clusters containing 10 or fewer flowers; Flowers have 3 lance-shaped and scaly petals; Petals change from light green to tan as flowers mature; Very small egg- or lance-shaped bractlets are visible at the base of each mature flower

12 Plantain, broadleaf Plantago major Plants have a rosette of waxy leaves with 5-7 parallel veins and elliptic in outline; Leaves are from 2-7 long, broad, lance- or egg-shaped and may be sparsely hairy; Roots are fibrous and most often shallow; Flower heads grow upright often reaching a height of ~8 and consist of slender, leafless spikes of inconspicuous and densely clustered flowers; Fruits are egg-shaped capsules ~1/10 1/5 long and contain 5 16 tiny, dull, orange to black seeds Plantain, buckhorn Plantago lanceolata Plants form a simple or branched taproot and a rosette of narrow, pointed leaves ~3 10 long that are shaped like a football; Leaves often have short hairs and leaf veins are parallel; Lower leaf surface is often ribbed; Flower stalks grow upright and if unmown may reach a height of ~2½. Flower heads resemble those of broadleaf plantain (Plantago major) however are shorter, most often ranging from 4/5 3 in height; Flowers are eventually replaced with egg-shaped capsules ~1/6 long containing 1 2 oblong and brown seeds Red sorrel Rumex acetosella Although the first few leaves appear egg-shaped, young plants quickly begin forming a rosette of distinct, arrow-shaped leaves ~1 3 long; Mature plants have rhizomes and at least 1 slender stem that grows upright from the crown, often reaching a height of more than 1 ; Leaves at or near the base of the plant are hairless, from 4/5 4 long and are arranged alternate to one another along the stem; Upper leaves may be linear or lance shaped and have a petiole; Flowers are clustered along a branching flower stem and change from yellowish green to reddish in color as they mature; Three-sided, eggshaped fruits ~1/17 long containing a single seed eventually replace flowers Star-of-Bethlehem Thymeleaf speedwell Ornithogalum umbellatum Veronica serpyllifolia Plants develop from energy-rich, oval-shaped bulbs and from a distance may be confused with wild garlic (Allium vineale) or wild onion (Allium canadense); Leaves ~4-12 long are shiny, dark green, hollow, and have a conspicuous white mid-rib; Star-shaped flowers with 6 white to purple petals develop on long leafless stalks; Plants spread laterally from one year to the next by way of bulblets around the parent bulb Plants are small and mat-forming by way of stolons; Stems are usually covered with very fine hairs; Leaves range from ¾ - 1½ long are oval, roundish or football-shaped, mostly hairless with smooth or finetoothed margins; Upper leaves are alternate while lower leaves are opposite; White to pale blue flowers

13 Virginia buttonweed with 4 petals are clustered; One petal is much smaller than the other 3; Flowers produce seed capsules that are broader than they are tall containing many small seeds Diodia virginiana A mat-forming plant with dark green leaves ~1¼ - 2½ long and ~½ - 1 wide arranged opposite and directly connected across the stem by a membrane; Stems root at the nodes and are occasionally hairy; Small, star-shaped flowers with 4 white petals are located in the axils of leaves; Each fruit consists of a small, hairy capsule with 2 seeds inside; A virus often causes leaves to become mottled and yellowish in color during late summer White clover Trifolium repens Plants have trifoliate leaves; Each of the 3 leaflets are oval-to-elliptic in outline and often have a white watermark partially encircling the base; Leaf margins have small serrations; White to pinkish white flowers are arranged in round heads atop flower stalks Wild garlic Allium vineale Plants have hollow, cylindrical leaves that develop from a basal bulb covered in a membrane; They have a distinctive garlic odor when mowed or crushed; In addition to a basal bulb, mature plants form offset bulblets adjacent to the basal bulb that are flat on one side Wild onion Allium canadense Plants are very similar in overall appearance to those of wild garlic but leaves are flat in shape and are not hollow; A fibrous coat forms around the central bulb and there are no offset bulblets Wild / Common blue violet Viola papilionacea Plants are usually 2-5 tall, rhizomatous, have heart shaped leaves that may cup inwards forming a funnellike shape and usually grow in clumps; Leaves are hairless and have rounded teeth along their margins; Flowers consist of 5 deep-blue-violet petals and are suspended on stalks with no leaves; Fruit is a capsule ranging from ~10 mm - 12 mm long Yellow woodsorrel Achilla millefolium Plants are rhizomatous and have trifoliate, slightly folded and heart-shaped leaves on top of long petioles; Leaves are arranged alternately along the stem and leaf margins are smooth but fringed with hairs; Stems range in color from green to pink