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| Wire Worm |
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Symptoms:
The wireworm is the larvae of the Click Beetle, a group which the gardener could well do without, the beetle is easily recognised by its narrow, bullet shaped body. The wireworms live in the soil and attack the roots of plants, they have very tough coats and they vary in colour from yellow to a rich brown. They take four or five years to mature, and during this time they feed on decaying matter as well as on the roots of a wide variety of plants. |
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| Japenese Beetle |
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Symptoms:
SymptomsThe adults are skeletonizers, that is, they eat the leaf tissue between the leaf veins but leave the veins behind. Attacked leaves look like lace, which soon withers and dies. The adults will often attack flower buds and fruit. The grubs can kill small seedling plants but most commonly damage turf. The turf first appears off color as if under water stress. Irrigating often masks infestations, but when withdrawn, severe damage soon appears. The turf feels spongy under foot and can be easily pulled back like old carpet to reveal the grubs. Large populations of grubs kill the turf in irregular patches. |
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| European Chafer Larvae |
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Symptoms:
Typical grub damage of thin turf, wilting and death in irregular patches can be found in the fall and early spring.
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| Dollar Spott |
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Symptoms:
The dollar spot fungus survives unfavorable periods as mycelia in infected plants and as stromata on foliage surfaces. Dissemination occurs when infected leaf debris is moved by equipment, people, animals, water, or wind. When the environment favors fungus activity, mycelium from within infected tissue or from stromata colonizes nearby healthy foliage. Under humid conditions, mycelial growth may extend out of the tissue into the air. When this aerial mycelium contacts a moist leaf surface, it may penetrate the leaf and cause an infection.
Disease Management1) Maintain adequate to high nitrogen fertility during the period of dollar spot activity. 2) Water thoroughly (deeply) but as infrequently as possible without causing drought stress. 3) Time irrigation to minimize leaf wetness. Avoid late afternoon and early evening irrigation. 4) Remove dew from turf by poling, dragging, whipping, or mowing. 5) Promote good air circulation over the turf by pruning or removing trees or shrubs and removing other barriers. 6) Temporarily increase mowing height during disease outbreaks. 7) Reduce compaction and thatch with core aeration. 8) Consult specialists for local recommendations of resistant cultivars for overseeding or reseeding areas that are chronically diseased. 9) Many fungicides are effective for control. With repeated use, the dollar spot fungus has become resistant to several chemical groups in some areas. Consult a local specialist for current recommendations. |
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| Army Worm |
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Symptoms:
Cutworms are so named because of their nocternal feeding habit of cutting off plants close to the ground. On golf course greens and tees, black cutworms and fall armyworms graze on the grass blades of short cut turf causing circular or finger-shaped sunken marks. Armyworms feed on grasses any time of the day and are known for their habit of moving and feeding, en masse, from one turfgrass area to another. They commonly eat everything green, leaving only a few stems. Bronzed cutworms occasionally damage cool season turf under the cover of snow. Other species of cutworms are relatively uncommon and their damage is minor. |
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| Bluegrass Billbug |
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Symptoms:
Billbug damage can appear from late June through August. Damage is most severe when summer drought stress is present. Light infestations often produce small dead spots similar to the turf disease, dollar spot. Sometimes the damage appears as irregular mottling or browning in the turf. Heavy infestations can result in complete destruction of the turf by August. The problem with diagnosis of billbug damage is that it resembles a variety of other turf problems. Turf managers confuse billbug damage with drought, disease, and infestations of chinch bugs, greenbugs or white grubs. Billbug damaged turf turns a whitish straw color rather than the yellow caused by greenbugs. Soil under damaged turf is solid, not spongy as in white grub attacks. Billbug damage on golf courses is often confused with drought stress or sprinkler head failure on tee and bunker banks and other sloped areas. To confirm billbug damage, grasp suspected turf and pull upward. If the stems break easily at ground level and the stems are hollowed out or are full of packed sawdust like material, billbugs are the culprit. Examine the plant crown and roots for evidence of further damage and presence of larvae.
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| Chinch Bug |
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Symptoms:
Chinch bug damage is usually first detected when irregular patches of turf begin to turn yellow then straw colored. The straw colored areas may be completely dead. These patches continue to enlarge in spite of watering. Apparently, feeding by chinch bugs blocks the water and food conducting vessels of grass stems. By blocking the water, the leaves wither as in drought and the manufactured food doesn't reach the roots and the plant dies. Damage is especially severe during hot, dry weather from June into September and is often mistaken for drought dormancy.
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| Cut Worm |
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Symptoms:
Cutworms are so named because of their nocternal feeding habit of cutting off plants close to the ground. On golf course greens and tees, black cutworms and fall armyworms graze on the grass blades of short cut turf causing circular or finger-shaped sunken marks. Armyworms feed on grasses any time of the day and are known for their habit of moving and feeding, en masse, from one turfgrass area to another. They commonly eat everything green, leaving only a few stems. Bronzed cutworms occasionally damage cool season turf under the cover of snow. Other species of cutworms are relatively uncommon and their damage is minor. |
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| Fairy Ring |
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Symptoms:
Whether fairy rings are initiated by the proliferation of a bit of fungus mycelium or by the germination of a basidiospore produced in the basidiocarp is not known. In any case, the fungus begins active growth at a point in soil or thatch and grows radically outward. The initial appearance of fairy rings is usually a small ring or a cluster of basidiocarps (mushrooms or puffballs). The diameter of the ring may enlarge annually by a few inches (centimeters) or more than 1.45 ft. (as much as 0.5 m). The fungus lives by decomposing organic litter in thatch or soil. The fungus may grow deeply in soil, with a dense, white, threadlike network of mycelium penetrating downward to depths of 8 in. (20 cm) or more. As a fairy ring fungus grows outward radically, older mycelium in the interior portion of the ring dies and releases nitrogen as it decomposes organic matter in thatch or soil, creating the possiblility for an inner ring of stimulated grass. In type 2 rings, the inner and outer zones of stimulation coincide because the dead zone is absent. The zone of inhibition contains grass plants that may be dormant or dead as a result of insufficient soil moisture. It is most likely that rings of droughted plants occur because of an extensive buildup of fungus mycelium, which renders soil hydrophobic and prevents water from infiltering. Other possible explanations for inhibited growth or plant death include the following: 1) nitrogen may accumulate at lethal concentrations of ammonia; 2) the fungus may produce toxic levels of hydrogen cyanide; 3) roots may be directly infected by the fungus (i.e., a pathogenic process); or 4) weakened grass plants may be killed by other pathogens or environmental stresses.
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| Leaf Spot |
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Symptoms:
The pathogens survive adverse periods as conidia and as dormant mycelium in infected leaves and plant litter. Spores are produced and are disseminated to leaves during warm, humid weather. Spore germination and infection processes lead to new leaf spots, whereupon new crops of spores may be produced. Prolonged periods of leaf wetness during warm weather are required for the occurrence of Cercospora leaf spots. |
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| Nerotic Ring Spot |
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Symptoms:
The pathogen is believed to survive unfavorable periods as sclerotia or mycelia in plant debris. Although little is known about the development ofLeptosphaeria korrae in soil, it attains maximum growth (3-6 mm per day) on potato-dextrose agar at 68-82 degrees fahrenheit (20-28 degrees celsius) and is inhibited at temperatures above 86 degrees fahrenheit (30 degrees celsius) or below 50 degrees fahrenheit (10 degrees celsius). Symptoms can occur throughout the growing season during cool, wet weather but generally appear in late spring and early autumn. Patches often fade with advent of warmer temperatures in the summer, but frequently reappear in some regions in response to heat and drought stress. Infection centers develop again in early autumn and may persist through the winter and early spring. Recovery is slow, and severly infected plants are easily removed from the turf because of the extensive rotting of roots, crowns, and rhizomes. Infected sod and mechanical equipment may spread the disease. Conditions that favor necrotic ring spot are similar to those that favor take-all-patch. The growth of L. korrae is more tolerant of soil moisture extremes than Kentucky bluegrass, drought stress may play a more important role in the development of necrotic ring spot than in take-all or summer patch. Necrotic ring spot can occur over a wide range of soil pH ( young turf are also damaged. |
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| Barnyard |
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Symptoms:
Barnyardgrass is a summer annual which has tillers which lie flat and form secondary roots resulting in a mat formation. The leaves of barnyardgrass are rolled in the bud and contain neither a ligule nor auricles; the sheath is open but compressed. The mid-vein is thick and keeled; roots are fibrous.Barnyardgrass spreads by seed which germinate in late spring and early summer. The seedhead is a coarsely branched green to purplish panicle with spiked awns.Barnyardgrass is found throughout North America and Mexico
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| Bermuda |
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Symptoms:
Bermudagrass is creeping perennial warm-season (C-4) turfgrass. Bermudagrass spreads by both rhizomes and stolons. Bermudagrass is grown as a fine turf throughout the transition zone and in the South. The ligule consists of a fringe of hair. Auricles are absent. The leaves of bermudagrass are folded in the bud, and the sheath is strongly compressed. The leaf is short, approximately 1/8 inch wide with rough edges. The roots of bermudagrass are deep and fibrous allowing it to be highly drought tolerant. The stolons root at the nodes forming a thick dense mat. The seedhead of Bermudagrass consists of 3 - 7 finger-like spikes. Seedheads are present during the summer months. Common bermudagrass can spread by seed, but hybrid varieties only spread by vegetative means.
Bermudagrass is found on open sunny areas. Bermudagrass does not grow in the shade. It can be found in turf, landscapes and in most cultural crops. Bermudagrass is very tolerant of low mowing, and can be found on both dry and wet soils.
Bermudagrass thrives in southern areas of the United States, south into the tropics. It can also be found in northern sections of the transition zone. |
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| Black Medic |
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Symptoms:
Black medic is normally a summer annual, but can act as a perennial in some conditions . It has a tap root, and spreads low to the ground, but it does not root from nodes on the stems. Black medic is more active on soils low in nitrogen fertility. The leaf is similar to clover and other legumes, having three leaflets. Black medic's center leaflet is on a separate petiole. The flower of black medic is a compressed cluster of bright yellow flowers in the shape of a globular spike on short branches. The seed pod will turn black at maturity. Black medic produces viable seed under normal mowing conditions.
Black medic is found throughout the continental United States |
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| Bristly Mallow |
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Symptoms:
Bristly mallow is a creeping perennial with shiny, light green leaves which alternate on the stem. Bristly mallow will root at nodes along the under side of the stems which appear as knobs. The leaves are similar to Venice mallow, but have more lobes on the leaf: six to seven versus three to five on Venice mallow. The margin of the leaves is toothed. Bristly mallow has a deep strong tap root. The flower of bristly mallow is an orange-red in color and appears in late spring to early summer. The flower is cup shaped and is located in the junction of the stem and leaf. Bristly mallow spreads by seed and by stoloniferous stems.
Bristly mallow is found in the lower Piedmont and coastal plain region of the Southeast, from Virginia to Florida. It can also be found in the gulf states west to Texas.
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| Broadleaf Plantain |
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Symptoms:
Broadleaf plantain is a shallow mostly fibrous rooted perennial. The leaves which develop in a rosette are large oval shaped with predominant veins. Broadleaf plantain is similar to several other plantain species, but does not have the purple color at the petiole of the leaves. The main growth period for broadleaf plantain is from June through September. The seed head is described as a rat-tail like seed head with flowers along the upper half of the seed head. Broadleaf plantain spreads by both seed and shoots from the roots.
Broadleaf plantain is found throughout all of the United States. |
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| Buckhorn |
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Symptoms:
Buckhorn plantain is a slender fibrous rooted perennial. The leaves develop in a basal rosette. They are long slender leafs approximately one inch across. The leaves have distinctive parallel venation. The main growth period for buckhorn plantain is from June through September. The seed heads are cylindrical spikes found at the tip of erect, leafless stalks which are 4 - 12 inches long. The stalks can be hard to cut with mowers. Buckhorn plantain spreads by seeds and shoots from the roots. Buckhorn is found throughout the entire continental United States.
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| Canadian Thistle |
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Symptoms:
Canada thistle is a 2 to 5 foot (0.6 to 1.5 meters) tall forb with deep, wide spreading, horizontal roots. The grooved, slender stems branch only at the top and are slightly hairy when young, becoming covered with hair as the plant grows. The oblong, tapering, sessile leaves are deeply divided, with prickly margins. Leaves are green on both sides with a smooth or slightly downy lower surface. Numerous small, compact (3/4 inch or 1.9 cm. diameter), rose-purple or white flowers appear on upper stems from June to September. Seeds are small (3/16 inch or 0.5 cm long), light brown, smooth and slightly tapered, with a tuft of tan hair loosely attached to the tip.
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| Carpet Weed |
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Symptoms:
Carpetweed is a summer annual with smooth prostrate branching stems forming circular mats. The leaves are light green in color, lanceolate in shape, being widest in the middle of the leaf and narrow at the tip and base. The leaves form in whorls containing 3 - 8 leaves. The flowers are white, contain five petals, and form clusters of two to five flowers. The clusters of flowers are formed in leaf axils. Carpetweed spreads by seed.Carpetweed is found throughout most the North America.
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| Chick Weed / Mouse Ear |
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Symptoms:
Mouseear chickweed is a winter perennial. The leaves are opposite, oblong and covered with hair. Mouseear chickweed grows prostrate but will have several upright stems, and can tolerate close mowing. Mouseear chickweed has a fibrous root system. The flowers of mouseear chickweed are white and contain 5 petals which are notched at the tip. Mouseear chickweed spreads by seed, but can root at the nodes.
Mouseear chickweed is found throughout United States into southern Canada.
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| White Clover |
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Symptoms:
White clover, found throughout the United States, is a shallow rooted winter perennial legume which spreads by stolons or above ground runners. The plant takes root from the stolons at nodes along the stems when they come in contact with the soil. The white clover plant has compound leaves divided into three leaflets which are all joined at a central point and originate at the nodes along the stems. Leaves may contain a white 'watermark'. White clover is adapted to many soils but tends to grow best in soils that are moist and low in nitrogen. The flowers are an aggregate of 20 - 40 individual flowers. They are white in color, although some have a slight pink tint. White clover flowers from May through September.
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| Crabgrass |
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Symptoms:
Crabgrass is a summer annual that germinates when soil temperatures reach a consistent 55 degrees F and is generally killed at the first frost. Crabgrass leaves are rolled in the bud; the first leaf appears short, wide and blunt-tipped. The ligule is tall and membranous with jagged edges, and the auricles are absent. The collar is broad with long hairs. Crabgrass is light green in color, coarse bladed and will root at the nodes when they touch the ground. A single crabgrass plant can produce up to 700 tillers. It is a bunch type grass.The inflorescence is a panicle of branches, with spikelets in two rows. A crabgrass plant can produce 150,000 seeds. Crabgrass needs warm soils and sunlight to germinate.
Crabgrass is found throughout the United States.
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| Speedwell |
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Symptoms:
Corn Speedwell is a winter annual that germinates in mid-fall. Speedwells have a short tap root to fibrous root systems and branching upright stems. The lower leaves are near round with toothed margins. The upper leaves are more pointed. The plant is covered with fine hairs. Corn Speedwell flowers are small and white to blue in color. The flowers are found in the leaf axis and the seed develops into a distinctive heart shape. Corn Speedwell is distributed throughout the United States.
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| Creeping Woodsorrel |
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Symptoms:
Creeping Woodsorrel is similar to yellow woodsorrel (Oxalis stricta), but is a creeping summer perennial. The leaves of Creeping Woodsorrel are deeply lobed, heart shaped, and may be green to reddish purple. Creeping Woodsorrel contains a slender taproot, and roots at nodes along slightly hairy stems. The flowers of oxalis corniculata are yellow, contain 5 petals, and form in clusters of 1 - 5 at the end of slender stems. Creeping Woodsorrel spreads by seeds. Creeping Woodsorrel is found in eastern North America, to North Dakota and Colorado.
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| Dandelion |
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Symptoms:
Dandelion is a winter perennial. The dandelion has thick fleshy tap root which often branches. New plants come from the root and root segments. Leaves form in a rosette, are deeply lobed, with the lobes pointing toward the base. Both the leaves and flower stems contain a white milky fluid. The flowers are yellow and are individual stems. The seeds are brown with tip containing white hairs. The yellow flower will turn to a white globular puff ball. The seeds are disseminated by wind. Dandelions spread by both seed and stems from the root. Dandelion is found throughout the United States.
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| Yellow Fox Tail |
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Symptoms:
Yellow foxtail is a summer annual which germinates when soil temperatures reach 65 degrees F. The leaves are rolled in the bud. The ligule is a fringe of hairs, and the auricles are absent. The collar is narrow and continuous. The blades of yellow foxtail contain hairs near the ligule. The growth habit of yellow foxtail is erect. The seedhead is a bushy, erect spike which resembles the tail of a fox.
Foxtail is found throughout the United States, but is most heavy in the Midwest and East.
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| Wild Garlic |
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Symptoms:
Wild onion and wild garlic are both winter perennials. The leaves are waxy, upright and needle shaped growing 8-12 inches long. The leaves of wild garlic are hollow and round and have a strong odor. The leaves of wild onion are solid and flat and appear directly from the bulb. Both plants grow from underground bulbs. The membrane-coated bulbs of wild garlic are flattenedon one side and have bulblets. Wild onion bulbs are white inside with a strong odor and are covered with a fibrous, scaly coat. The white to light green flowers of wild garlic develop on short stems above aerial bulbs. Wild onion does not have a stem; white to pink flowers with six eliptical segments. Both wild onion and wild garlic spread by bulbs, seed and bulblets. Both plants flower from April through June. Both wild onion and wild garlic are distributed throughout the United States.
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| Goose Grass |
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Symptoms:
Goosegrass is a prostrate-growing summer annual. The leaves are folded in the bud. Goosegrass grows in a clump with the base of the leaves being distinctively white to silver in color. The ligule is toothed, membranous, and divided at the center. Goosegrass contains hairs only at the base of the leaf. Goosegrass seedheads contain 3 -7 spikes that form at the tip of the seed stalk. The seeds are attached in a zipper appearance on the spike. Goosegrass spreads by seeds that germinate later in the season than other annual grasses.Goosegrass seedheads contain 3 -7 spikes that form at the tip of the seed stalk. The seeds are attached in a zipper appearance on the spike. Goosegrass spreads by seeds that germinate later in the season than other annual grasses. Goosegrass is found in the United States from the transition zone south.
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| Ground Ivy |
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Symptoms:
Ground ivy is a creeping winter perennial. The leaves are round to kidney shaped with round toothed edges. The leaves are opposite on long petiole attached to square stems that root at the nodes. It is usually found in moist shaded areas, but also tolerate sun very well. Ground ivy will form dense mats which can take over areas of turfgrass.The flowers of ground ivy are blue to lavender and grow in clusters. It usually flowers in the spring. Theflowers are funnel shaped and are located at the leaf axis or near the tip of the stem. Ground ivy spreads by stolons and sometimes by seed. Ground ivy closely resembles common mallow. Ground ivy is more common in the East, but can be found throughout the United States.
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| Hawkweed |
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Symptoms:
There are two hawkweeds, a yellow and an orange. The vegetative characteristics are similar, but the color of the flowers is different. Hawkweeds are winter perennials. Hawkweed grows from a basal rosette, forming patches from rhizomes and stolons. The leaves, stems and flower stalks are covered with hair. The leaves are oblong and club shaped. The margins of the hairy leaves are smooth. Hawkweed flowers resemble dandelions, but are smaller and appear several weeks after dandelions. The flowers form in clusters.
Hawkweeds are found throughout the eastern United States.
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| Henbit |
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Symptoms:
Henbit, a member of the mint family, is an upright winter annual that blooms in the spring. The leaves are rounded on the end with rounded toothed edges that grow opposite one another on square stems Upper leaves lack petioles. Henbit can grow from 4 to 12 inches tall on weak stems. Although an upright plant, weak stems sprouting from the bottom may lay almost horizontal. Henbit can be confused with purple deadnettle. The leaves of purple deadnettle, however, are more pointed at the end and are slightly scalloped. The lower leaves of purple deadnettle are on long petioles, the upper leaves are on short petioles. The flowers of henbit are purple, tubular shaped and form in the whorls of the upper leaves. Henbit spreads only by seed and is generally not a problem in dense, vigorous turfgrass sites. Henbit is found throughout the United States.
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| Thistle |
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Symptoms:
Yellow thistle is a winter annual or sometimes a biannual. The initial leaves form in a rosette. The mature leaves contain large toothed and cut lobes. The mature leaves are very spiny. Yellow thistle spreads by seeds attached to tuffs of soft white hairs which help in the spreading of the seeds. The flowers are produced in the late spring and seeds are produced over the summer. Yellow thistle is found along the East Coast form Maine to Florida. It can be found along marshy areas west to Texas.
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| Prostate Knotweed |
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Symptoms:
Prostrate Knotweed is a summer annual, which forms dense patches. Prostrate knotweed is probably the earliest of the summer annuals to germinate in the spring. Prostrate knotweed is often confused with first-leaf crabgrass. Prostrate knotweed is a prostrate weed that produces a thin tap root and multiple branched stems. Even though knotweed does not root down at the nodes of the stems, a single plant can form a dense mass up to three feet across. Prostrateknotweed tolerates extremely compacted soils and is often found in high traffic areas. The leaves appear alternately on the stems, and differ in the color of green depending on the age of the leaf, with older leaves being a less intense green. The stems will be knotty and have a paper like sheath. The flowers of knotweed are small pink to white and form in clusters in the leaf axis. Flowers form in late spring. Knotweed spreads by seed. Prostrate knotweed is found throughout North America.
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| Wild Onion |
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Symptoms:
Wild onion and wild garlic are both winter perennials. The leaves are waxy, upright and needle shaped growing 8-12 inches long. The leaves of wild garlic are hollow and round and have a strong odor. The leaves of wild onion are solid and flat and appear directly from the bulb. Both plants grow from underground bulbs. The membrane-coated bulbs of wild garlic are flattenedon one side and have bulblets. Wild onion bulbs are white inside with a strong odor and are covered with a fibrous, scaly coat. The white to light green flowers of wild garlic develop on short stems above aerial bulbs. Wild onion does not have a stem; white to pink flowers with six eliptical segments. Both wild onion and wild garlic spread by bulbs, seed and bulblets. Both plants flower from April through June. Both wild onion and wild garlic are distributed throughout the United States.
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| Pennywart |
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Symptoms:
Pennywort, also called dollarweed, is a summer perennial weed. The leaves of pennywort are round in shape, approximately 1 inch in diameter. The dark green leaves are glossy, with scalloped edges and are on long slender petioles. The petiole of pennywort is attached to the center of the leaf, not to be confused with dichondra in which the petiole is attached to the edge of the kidney shaped leaf. The pennywort flower is small with 5 white petals and forms in clusters on the end of long stems. Pennywort spreads by seed and rhizomes. Pennywort is found along the Atlantic coast from Maine to Florida and westward to Minnesota, Texas, Utah, Arizona and California. Pennywort is also found in Nova Scotia, British Columbia, the West Indies, Mexico, Central and South America and Southern Europe and Tropical Africa.
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| Poison Ivy |
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Symptoms:
Poison ivy can be an erect woody shrub or a climbing vine. The leaves alternate on red stems. They are glossy and have 3 leaflets 2 - 3 inches long that can be smooth or toothed; leaves turn red in the autumn. As with other members of the Rhus family (poison oak and poison sumac), poison ivy can cause severe skin irritation. The yellowish flowers of poison ivy form in clusters in the axis. The flowers have five green petals and are usually inconspicuous. Poison ivy forms a small creamy white berry in the fall containing a single seed. Berries generally remain attached to the stem through the winter. Poison ivy spreads by rhizomes and seeds and prefers shaded areas. Poison ivy has a fibrous root system.
Poison ivy is found throughout the midwestern, northern and eastern United States.
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| Quackgrass |
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Symptoms:
Quackgrass is a blue-green perennial. The leaves are rolled in the bud, The ligule is short and membranous, auricles are long and clasping. The upper surface of the leaf blade is rough. Quackgrass produces long sharp tipped aggressive rhizomes. Quackgrass remains green year round. The seedhead of quackgrass is a spike containing two rows of spikelets. Awns are usually present. Quackgrass is found throughout the Northern United States.
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| Purslane |
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Symptoms:
Purslane is a summer annual with prostrate growth from a tap root and fibrous surface roots. The leaves are thick and waxy, resembling a Jade plant. The leaves usually alternate, with a cluster at the tip of the stem. Stems are thick, red in color, and branch out from a central point, forming a mat up to 1 foot in diameter. The flower is solitary, yellow in color and has 5 petals. The flower is found in the leaf axis or at the tip of the stem. Purslane flowers from May to November and spreads by seeds, which germinate in the spring, or by stem fragments. Purslane is found through out the United States, but less in the Pacific Northwest.
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| Poison Oak |
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Symptoms:
Poison oak is identified by 1 ½ to 3 inch long leaflets with two to seven deep lobes resembling oak leaves. Lateral leaflets appear without stalks on viny stems about 3 to 4 feet tall. Like poison ivy, leaflets are grouped three per leaf, and flowers are yellowish. Poison oak is found throughout the southeast and along the Pacific coast in the United States.
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| Red Sorrel |
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Symptoms:
Red sorrel, also referred to as sheep sorrel, is a summer perennial. The leaves alternate and form a basal rosette. The older leaves are arrowhead shaped with two basal lobes attached to a petiole. Leaves formed along the stem are more elongated and usually lack the basal lobes. The margins of the leaf are smooth. The leaves become thick and fleshy over the summer months. The root red sorrel is a shallow yellow taproot, combined with multiple rhizomes. Flowers are produced from May to September. Male and female flowers are produced on separate plants. The male flowers are yellow-green and the female flowers are reddish-brown. The flowering stems of red sorrel can be one or many developing from a crown or rhizome. Red sorrel spreads by seeds and rhizomes.
Red sorrel is found throughout the United States.
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| Spurge |
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Symptoms:
Spotted spurge is a summer annual. While similar to prostate spurge, there are several subtle differences in the two varieties. Spotted spurge has a more erect growth habit than prostrate spurge. They have similar leaves, which are small and oblong shaped with an irregular red to purple spot, but the leaf of spotted spurge is slightly larger than that of prostrate spurge. Both spurges will have leaves that grow opposite on the stem, but spotted spurge has fewer leaves per stem. Both spurges contain a milky sap in the stem. Prostrate spurge roots at the nodes, spotted spurge does not. The flower of spotted spurge is small and green in color. It germinates in mid spring and flowers from June to September. Both spotted and prostrate spurge reproduce from seed, although prostrate spurge also roots at the nodes. Both spurges are found throughout the United States.
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| Wild Strawberry |
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Symptoms:
Wild strawberry is a low trailing winter perennial, spreading by stolons. The leaves of wild strawberry are similar to cultivated strawberries. The leaves are trifoliolate on long hairy petioles. The leaves have toothed margins. The flowers which are produced from April to June are white with yellow stamens and pistils, and contain five petals. The fruit is a red strawberry with many small seeds in pits on the surface. Wild strawberries reproduce from seed and from runners. Each plant forms multiple runners which root at the nodes and form new plants. Wild strawberries are found throughout most of the United States and Canada.
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| Violets |
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Symptoms:
Wild violet is a winter perennial, growing 2 - 5 inches tall. It can have a tap root or a fibrous root system, and also can produce rooting stolons and rhizomes. The leaves can vary but usually are heart shaped, on long petioles with scalloped to shallow rounded margins. The flowers of wild violet range from white to blue to purple and appear from March to June. Wild violet flowers are pansy-like with three lower petals and two lateral petals on long single flower stalks. Wild violets are found throughout the United States, except for the Rocky Mountains. Wild violets are more common where they are sold as ornamental ground covers.
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| Nutsedge |
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Symptoms:
Sedges have triangular stems with waxy grass-like leaves which alternate. Sedges are not grass plants, but seedlings may be mistaken for grass. The leaves on both sedges are waxy and have an up right growth habit and a prominent midrib. Both sedges have underground root systems containing rhizomes and underground tubers which accomplish most of the reproduction. On yellow nutsedge, the tubers (nutlets) form at the end of whitish rhizomes. Purple nutsedge forms chains of tubers along brownish rhizomes.The flowers of yellow nutsedge are yellowish; the seedhead color of purple nutsedge is red-purple to brown. Both seedheads are on triangular stems. Both spread mainly by germinating underground tubers, which are the only part of the plant that over-winters. A yellow nutsedge tuber can produce 1,900 plants and 7,000 new tubers in a single growing season1. Sedges do well where soil has poor drainage.
Yellow nutsedge is found throughout the United States; purple nutsedge is primarily found in the warm humid southern states |
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| Powdery Mildew |
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Symptoms:
The pathogen overwinters primarily as mycelium within living infected plants. In areas with harsh winter climates, the fungus survives as ascospores in cleistothecia embedded in infected plants or debris. Conidia produced on surviving mycelia in the spring or ascospores that were not discharged the previous autumn become airborne. Conidia are the dominant spore form that serves as primary inoculum in turfgrasses. The conidia that land on a susceptible plant germinate quickly and can infect the host. New conidia may be produced within 1 week on newly infected leaves. The disease is, therefore, capable of spreading very rapidly. The conidia live only a few days, but they germinate over a wide temperature range (34-86 degrees F, 1-30 degrees C), and hyphal growth does not require a film of free moisture on the leaf surface. Cleistothecia are formed as infected leaves mature or die prematurely, and the ascospores are generally discharged after rains in the autumn.
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| Red Thread |
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Symptoms:
The fungus survives unfavorable periods as sclerotia (red threads) on infected leaves or lying in the thatch. These threads survive high 90 degrees F (32 degrees C) or low -30 degrees F (-20 degrees C) temperatures and remain viable for up to 2 years when dry. The pathogen is spread locally as arthroconidia or threads moved by running water, equipment, people, and animals. The arthroconidia and infected plant debris may also become windborne and bring about long-distance dissemination. The importance of basidiospores in the disease cycle is uncertain, but they may be produced abundantly. A film of moisture over the surfaces of leaves or leaf sheaths is necessary germination of mycelia in the threads or of arthroconidia (and possible basidiospores). The fungus may kill leaves within 2 days of primary infection.
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| Rust |
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Symptoms:
Infected turgrass foliage serves as the overwintering site for the mycelium and urediniospores of rust fungi in areas with mild climates. When weather is conducive to spore germination or mycelial growth, the foliage becomes infected and new uredinial pustules are formed. Urediniospores may also be transported over long distances by wind, and those from warm regions may serve as sources of windblown primary inoculum for colder regions where mycelium and urediniospores are not able to survive winter. Within 2 weeks after infection has been completed, urediniospores are produced in abundance and are released from the uredinia. This spore constitutes the repeating stage of rusts, with new cycles beginning every 2 weeks. Most rust fungi can also produce another spore type, the teliospore, when plant foliage becomes mature or dries slowly. These conditions occur primarily on unmowed grasses, and the teliospore stage is therefore of minor or no importance on most turgrasses. The teliospore, when produced, may overwinter and then germinate to produce a third spore type, the basidiospore. These spores become airborne, and if they land on a susceptible nongrass host, they can germinate and cause a new infection. For example, Puccinia graminis basidiospores only can infect barberry (Berberis canadensis Mill. and B. vulgaris L.). Basidiospores germinate on and infect barberry, and two more spore types known as pycniospores and aeciospores are formed. Aeciospores can infect only the grass plant, giving rise to urediniospores and thus completing the life cycle. It must be emphasized, however, that spore types other than urediniospores are rarely important for the occurence of rusts on turfgrasses.
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| Snow Mold |
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Symptoms:
Prolonged periods of deep snow cover favor this disease. The optimal temperatures for the pathogen's growth range from 40-60 degrees F (5-15 degrees C). Growth continues at temperatures slightly below 32 degrees F (0 degrees C). Sclerotia serve as the survival structure of the sclerotial strains. The means of persistence for the nonsclerotial strains are not known.
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| Spring Dead Spot |
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Symptoms:
The causal fungi appear to grow most actively during the autumn and spring when temperatures are cool and soil is moist. Growth of Leptosphaeria narmari in soil is most rapid at 50-68 degrees F (10-20 degrees C), whereas L. korrai grow optimally on potato-dextrose agar at 78 degrees F (25 degrees C). Colonization and infection of roots by L. korrae and Ophiosphaerella herpotricha are likely to occur when soil temperatures range from50-78 degrees F (10-25 degrees C), with maximum injury occurring at 59 degrees F (15 degrees C). Roots of bermudagrass grow most rapidly at 95 degrees F (35 degrees C) and extremely slowly at 59 degrees F (15 degrees C). Causal fungi therefore possess a competitive growth advantage over hosts from autumn to spring. Damage is expressed most clearly when foliar growth resumes in the spring. In North America, spring dead spot occurs primarily in areas where the average daily temperature during November (late autumn) is below 55 degrees F (13 degrees C). Similarly, mean temperatures of 54-57 degrees F (12-14 degrees C) occur in Australia during winter (June to August). Spring dead spot is a disease of mature turfs that are intensively managed. The disease is less severe or absent on turfs maintained at low levels of fertility. Soils heavy with clay content and heavy applications of nitrogen in late summer have increased the severity of spring dead spot.
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| Summer Patch |
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Symptoms:
The pathogen is believed to survive the winter months as mycelia in previously colonized plant debris and in perennial host tissue. Colonization and suppression of root growth has been shown to occur between 70 and 95 degrees F (21-35 degrees C) under controlled environmental conditions, with optimum disease development at 82 degrees F ( 28 degrees C). In the field, infection commences in late spring when soil temperatures stabilize between 64 and 68 degrees F (18-20 degrees C). The fungus moves from plant to plant by growing along roots and rhizomes. Symptoms develop during hot (86-95 degrees F, 30-35 degrees C), rainy weather or when high temperatures follow periods of heavy rainfall. Patches may continue to expand through the summer and early autumn and are often still evident the following growing season. Summer patch may be spread by aerification and dethatching equipment as well as by the transport of infected sod.
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| Sod Web Worm |
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Symptoms:
In lawns, sports fields and other high cut turf, sod webworm damage is rare. When it occurs during the summer months, the turf simply appears thin and leaf margins may be ragged in appearance. Spring damage most commonly occurs when the overwintered larvae begin feeding yet the turf is slowly growing. This damage usually looks like the disease, dollar spot. Round to slightly irregular spots, two to six inches in diameter, of yellow to frosted turf appears scattered across the lawn. On golf courses, the most important sod webworm damage is caused larvae that have overwintered in greens and tees. These larvae build silken tunnels to the surface and feed in linear trail just below the mow line. Their feeding trail is covered with silk to which sand and soil particles are attached. These areas usually appear as brown crescents that are one to two inches long. Heavy infestations in summer months cause irregular sunken trails in the short cut bentgrass surfaces. These intermingling trails are often misdiagnosed as some strange disease. Starlings are very good at detecting sod webworms in short cut bentgrass as well as higher cut turf. If these birds persist at feeding in certain areas, use a soap drench to determine presence of sod webworms or other insects. Sod webworms DO NOT form loose webbing over the turf surface. Circular patches of webbing that appear on turf surfaces, usually the size of a quarter and often coated with dew are the result of spider activity. |
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