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BUCKEYE YARD AND GARDEN LINE 2009-18 08/06/09 From: Pam Bennett, Barb Bloetscher, Joe Boggs, Cindy Burskey, Jim Chatfield, Erik Draper, Dave Dyke, Gary Gao, David Goerig, Tim Malinich, Becky McCann, Amy Stone, and Curtis Young. This is the 18th 2009 edition of the Buckeye Yard and Garden Line (BYGL). BYGL is developed from a Tuesday morning conference call of Extension Educators, Specialists, and other contributors in Ohio. BYGL is available via email, contact Cheryl Fischnich [ This e-mail address is being protected from spambots. You need JavaScript enabled to view it ] to subscribe. Additional Factsheet information on any of these articles may be found through the OSU fact sheet database [ http://plantfacts.osu.edu/ ]. BYGL is a service of OSU Extension and is aided by major support from the ONLA (Ohio Nursery and Landscape Association) [ http://onla.org/ ; http://buckeyegardening.com/ ] to the OSU Extension Nursery, Landscape and Turf Team (ENLTT). Any materials in this newsletter may be reproduced for educational purposes providing the source is credited. BYGL is available online at: [ http://bygl.osu.edu ], a web site sponsored by the Ohio State University Department of Horticulture and Crop Sciences (HCS) as part of the "Horticulture in Virtual Perspective." The online version of BYGL has images associated with the articles and links to additional information. Following are the participants in the August 4th conference call: Pam Bennett (Clark); Barb Bloetscher (Entomology/C. Wayne Ellett Plant and Pest Diagnostic Clinic (CWEPPDC)); Joe Boggs (Hamilton); Jim Chatfield (Horticulture and Crop Science); Erik Draper (Geauga); Dave Dyke (Hamilton); Gary Gao (Delaware); Dave Goerig (Mahoning); Dave Shetlar (Entomology); Amy Stone (Lucas); Nancy Taylor (CWEPPDC); and Curtis Young (Hancock). In This Issue:
1. WEATHERWATCH. The following weather information summarizes data collected at various Ohio Agricultural Research Development Center (OARDC) Weather Stations spanning the dates: August 1-August 5, 2009, with the exception of the soil temperatures which are readings from Wednesday, August 5, 2009 at 6:05 p.m. Most BYGLers reported being on the receiving end of recent rains, although Amy Stone mentioned that the Toledo area remains dry. Thankfully, Ohio did not receive the torrential rain that caused flooding in several Kentucky cities on Tuesday, August 3, 2009. Areas near Lexington, Kentucky received 6" of rain within an hour which caused flash floods earlier this week.
For a link to the OARDC Weather Stations, visit: [ http://www.oardc.ohio-state.edu/centernet/weather.htm ]
2. HORT SHORTS. A. VEGETABLE GARDENING 101, AUGUST 6, 2009 - SMUTTY CORN DISGUSTED HOME GARDENERS. Curtis Young talked with a home gardener who brought in a sample of sweet corn with corn smut. It turns out that the corn plant may be infected at any time in the early stages of growth, but becomes less susceptible after formation of the ear. Above‑ground parts may be infected, but it is more common to see smut galls on the ears, tassels, and nodes than on the leaves, internodes, and aerial roots. The smut gall is composed of a great mass of black, greasy, or powdery spores enclosed by a smooth white covering of corn tissue. The gall may be 4‑5" in diameter. When leaves are infected, small pustules develop, usually on the midrib, causing some leaf distortion. After the spores mature, the outer covering becomes dry and brittle, breaks open, and the spores sift out. Greatest yield losses occur when the ear becomes infected or if smut galls form on the stalks immediately above the ears. Though looking very gross, corn smut is an extremely common disease of sweet, pop, and dent corn in Ohio and throughout the world. In Mexico, immature smut galls are consumed as an edible delicacy known as cuitlacoche, and sweet corn smut galls have become a high value crop for some growers in the NE United States who sell them to Mexican restaurants. Most BYGLers and the home gardener were not very eager to try cuitlacoche. To manage this disease in the home garden, remove smut galls before they break open and bury or burn them. This must be done on a community basis, however, in order to be effective. Plant corn hybrids or varieties that are resistant to smut. Field or dent corn is generally more resistant than sweet or popcorn. In sweet corn, the larger, later‑growing varieties usually are more resistant than the smaller, early varieties. Highly susceptible sweet corn varieties include: Spring Gold, Duet, Golden Beauty, Silver Queen, and Country Gentlemen Hybrid. B. PLANTS OF THE WEEK. Read all about perennials and landscape trees and shrubs in the ONLA publications "Perennial Plants for Ohio" and "Landscape Plants for Ohio." The descriptions and photographs of plants were provided for these publications by the OSU ENLT Team along with other industry plant lovers. These full-color publications are available at [ http://Buckeyegardening.com ] for $5.00. Click on "garden store" and then "ONLA plant guides." ONLA members can purchase these in quantities at a reduced price at [ http://onla.org ]. *ANNUAL - VINCA (Catharanthus X hybrida). These annuals are providing outstanding color in Ohio landscapes at this time. The bold flower colors and glossy green leaves provide season-long interest with practically no maintenance (no deadheading). They are drought tolerant and start to bloom in early summer and last until a hard frost in the fall. These plants prefer hot, sunny locations and don't tolerate cold soils. Many gardeners lose them early in the season by planting before the soil warms up. There are many cultivars as well as colors. Most plants grow to around 1' tall by 1' around. Some of the cultivars are more of a ground cover or hanging basket plant. *PERENNIAL - RESURRECTION, SURPRISE, MAGIC, OR NAKED LILY (Lycoris squamigera). Surprise! These interesting bulbs are showing up in gardens all over Ohio - without leaves! First the plants send up 24" tall stalks that hold beautiful amaryllis-like pink flowers. Then, the strappy leaves appear after the flowers. The plants are extremely hardy and add a lot of show to the August garden. There are so many common names for this plant that it's important to use the Latin name in order to make sure you are getting the right plant. *WOODY - JAPANESE MAPLE (Acer spp.). Normally, by this time of the year, Japanese maples can look pretty crummy in the landscape because of heat and leaf scorching. However, cooler July temperatures have been kind to these trees and many are really showing off right now. This small tree is excellent for the landscape if planted in the right location. They prefer partial shade and moist well-drained soils. There are numerous cultivars with a wide variety of leaf sizes, shapes, colors, as well as tree sizes and shapes. The graceful, layered horizontal branching structure also adds elegance to the overall structure of the landscape. Try 'Bloodgood' with the deep reddish-purple leaves or the smaller growing trees that have red foliage such as 'Ever-red' and 'Garnet'. *THE WEEKLY WEED - HAIRY GALINSOGA (Galinsoga ciliate). Whether you are involved in the green industry or your own private garden, chances are you have seen this week's featured weed in your landscapes. This plant is a summer annual. It grows erect to just under 2' and branches out extensively. The leaves are somewhat egg-shaped that are pointed at the apex. Its flowers are small, and numerous with white, ray petals that bloom from June-October. Like most plants that are classified as weeds, it is a profuse seeder. Its seeds tend to grow best in fertile soils. It is a member of the Compositae (Aster) family and is distributed around the world but is most common in the eastern United States. Let's all give an up-rooting heave-ho to the Hairy Galinsoga, our weekly weed.
3. GREEN SHORTS. A. ALONG CAME A SPIDER. This is the time of the year when calls to Extension offices concerning spiders begin to balloon. Spiders are predators and populations of these meat eaters take much longer to swell compared to plant eaters. There are over 600 species of spiders found in Ohio; most feed primarily on insects. Two of the more interesting spiders currently being seen are the FUNNEL WEAVERS (Family: Agelenidae) and the SHEETWEB WEAVERS (Family: Linyphiidae). Both weave horizontal webs and their gossamer creations are a common sight cascading over branches or hanging from branch tips on landscape plants. Funnel weavers produce large, flat, sheet-like webs spun across grass, under rocks or boards, or over the branches of shrubs such as yews and junipers. The webs slope gently towards a narrow funnel or tube where the spider resides, awaiting its next victim. The spiders are medium-sized and resemble small wolf spiders. Funnel webs can become very evident when covered by early morning dew, or when they snare dust during droughty conditions. Sheetweb weavers spin small flat or slightly curved webs that are suspended from vegetation. The spiders are tiny with some species being the smallest-sized spiders found in Ohio. Indeed, the diminutive spiders may go unnoticed as they hang suspended beneath their web. Unlike funnel weavers and many other spiders that zip onto their webs to seize and dispatch their trapped prey, sheetweb weavers attack their tangled prey from beneath. They actually bite through their web. Although there are several insecticides labeled for spider control, this is not a recommended practice. Spiders are important in reducing insect pest populations. Homeowners are urged to practice restraint, appreciation, and understanding. Spiders provide a great service by reducing the need for controlling more significant pests. B. SELECTING PLANTS FOR RAIN GARDENS. Plants used in storm water management applications, such as rain gardens, have been typically thought of as those that can tolerate both wet soils in the late winter and spring and dry soils in the summer. However, what you should be really concerned with is selecting plants that will thrive in the different ecosystems that can be created by rain gardens. These can vary widely, as in any other landscape situation. Native plants are often suggested for use in rain gardens based on the belief that they are better adapted to local conditions than non-native plants. Consider using all plants that do well in your area under the soil and site conditions found in your rain garden. Both native and non-native plants should be considered. Consider all types of plant materials, including trees and shrubs that are relatively low maintenance, instead of only selecting the more traditional herbaceous plant materials associated with infiltration plantings. Remember that a garden can provide many functions in addition to storm water management, including shade and wildlife habitat. It is important that you consider many other factors, including the following, when making your plant selections: Recommendations/local trials, hardiness, light, moisture, fertility and pH, size, aggressiveness, color, texture, bloom time, appearance, and deer resistance. For a list of plants recommended for landscape applications in southwest Ohio and further information on rain gardens refer to "Landscape Systems for Managing Storm Water in Southwest Ohio - Steps for Getting Off the Storm Water Grid" at: [ http://hamilton.osu.edu/landscape-stormwater-management ]. Most of the plants listed in that publication will also do well in most other areas of Ohio. Consult with your local Extension office to determine which of those listed, and others, will work for your situation.
4. CLINIC CLIPS. Sawtooth grain beetles and its larvae were submitted to the CWEPPDC from a box of cereal. Since these grain pests are not likely to fly, the infestation was contained to the single product purchased. Glabrous cabinet beetles were submitted from a pest control company, when the grain and protein loving beetles were found on the backseat of a car. A luna moth was reported in a wooded Columbus neighborhood. These rare but beautiful luminous green moths are in the silk moth family. Their caterpillars are not considered to be pests. Spider mite damage was seen on several spruce samples and a report of mature iris borers destroying iris corms was handled. On Austrian pine, we saw Dothistroma needle blight symptoms resulting from infections that occurred last year. We continue to receive boxwood samples suffering from winter injury coupled with Volutella canker; the cankers had progressed to the base of the plants. Fireblight samples continue to come in on crabapple and ornamental pears. We tested three samples of hosta for Hosta Virus X using serological test procedures, two tested positive. Armillaria root rot is suspected in the decline of two red oak samples. Verticillium wilt was detected in a sugar maple and tomato sample. Also on tomato, bacterial canker and Septoria leaf spot were detected.
5. BUGBYTES. A. MAGNOLIA SERPINTINE LEAFMINER CATERPIILAR. The highly visible symptoms of the magnolia serpentine leafmining caterpillar (Phyllocnistis magnoliella) are becoming evident on bigleaf magnolia in southwest Ohio. The tiny caterpillars of this aptly named moth feed close to the upper leaf epidermis, producing long, thin, serpentine mines that appear as silvery tracks snaking across the leaf surface. Hosts for this leafminer includes southern, cucumber, sweet bay, star, umbrella, and the aforementioned bigleaf magnolias. Large numbers of mines on a single leaf can cause the leaf to turn brown and drop from the tree. The life-cycle for this moth is apparently poorly understood, so there is little information supporting the effective timing of insecticide applications to control the caterpillars. Fortunately, heavy populations involving multiple leaves rarely occur. Thus, populations may be effectively managed by removing and destroying infested leaves when mines first appear. B. BLISTER BEETLES FESTER. Curtis Young and Joe Boggs reported that packs of swarming MARGINED BLISTER BEETLES (Epicauta pestifera) were observed consuming the leaves of a number of different herbaceous perennials in southwest and western Ohio, respectively. Aside from occasionally producing noticeable defoliation, these beetles also pack a serious defensive punch! The beetle's blood contains cantharidin, a chemical that can cause severe blistering of the skin if the beetles are mishandled, hence the common name. This chemical can also be toxic to people and animals if ingested. Oddly, cantharidin is extracted from a European blister beetle to produce "Spanish Fly." Several species of blister beetles may be found in Ohio. They range in size from 3/4-1 1/4" long. The beetles have long legs and narrow, elongated soft bodies. Their heads appear almost bulbous because they are much wider than the pronotum ("neck"). The beetle's flexible front wings often fail to extend to the tip of the abdomen. Margined blister beetles are so named because the margins of their black wings are bounded by gray edges. The body of the striped blister beetle (E. vittata) has black and orangish-yellow stripes, and the body of the black blister beetle (E. pennsylvanica) is … black. The adults of most species are plant feeders and may be found consuming leaves or flowers on plants in the families Amaranthaceae, Asteraceae (= Compositae), Fabaceae (= Leguminosae), and Solanaceae. The larvae are specialized predators. Some feed on grasshopper eggs while others feed in the nests of solitary bees where they consume bee eggs, larvae, and food stored in the nest. Blister beetle adults may emerge en masse and produce rapid plant damage. Fortunately, their visits are usually very short lived, lasting only a week or two. They can be easily controlled, if necessary, by using a gloved hand to knock them into a bucket of soapy water (to be carefully disposed!), or by using an insecticide labeled for the host plant. C. DISTORTED CONEFLOWERS. The handiwork of an eriophyid mite that affects Echinacea flowers is becoming very apparent on coneflowers in southwest Ohio. The mites live inside the developing flower buds and suck nutrients from the base of the flowers. As a result, green to reddish-green elongated rosette-like tufts of stunted and distorted flower parts will sprout from the tops or sides of the cones of coneflowers. Not only is the damage unsightly, it can also seriously reduce seed production. Little appears to be known about this mite. It is a yet-to-be identified eriophyid, and lacks a scientific name as well as an approved common name. The mite is commonly referred to as the "CONEFLOWER ROSETTE MITE" because of its host plant and the family name for these mites (Eriophyidae). However, the mite's minimal taxonomic condition will no doubt eventually change since it is becoming a common problem on coneflowers in perennial gardens and naturalized areas in Ohio and elsewhere in the U.S. In past years, Dave Shetlar has observed thousands of these mites leaving rosettes to crawl to the tips of the distorted mass after a rain event. This behavior is common to eriophyid mites and allows them to be picked-up by the wind to be blown ("ballooned") to other coneflowers. Pollinators probably also provide lifts to new horizons. Management options currently focus on sanitation. The mites are probably out of the effective reach of miticides since they live deep inside the rosettes. Affected flower heads should be removed and destroyed throughout the season at the first sign of the rosettes. Additionally, plants that have had infested flower heads during the growing season should be cut to the ground in the fall. The cut plant tissue as well as debris beneath the plants should be raked and destroyed. There is anecdotal evidence that a consistent sanitation program will significantly reduce mite infestations. D. POTTER WASPS. Joe Boggs reported observing the unusual nests of potter wasps (Eumenes sp.) hanging from juniper twigs. The wasps belong to the family Vespidae, which includes paper wasps, yellowjackets, and hornets; however, potter wasps create their nesting artistry using clay rather than paper. As their common name describes, potter wasps fashion small rounded jug-like nests out of clay, and they attach the nests to leaves, twigs, or to structures such as window seals. The 3/8-3/4" long potter wasp females don't gather mud for their nests. They first collect water and then they mix it with dry soil using their mandibles. The mud mixture is then transported to the nest-making site where it is fashioned into individual pots ranging in size from 1/4-3/8" in diameter. The entire construction process may require a couple of hundred trips over several hours. As the pot nears completion, the female lays a single egg attached by a thread to the inside surface of the nest. They then provision the pot with a caterpillar or beetle larva that has been paralyzed by a sting. Once provisioned, the pot is sealed with a clay plug leaving the hapless paralyzed prey to await an appointment with the wasp's hatchling larva. Thus, potter wasps are considered beneficial … to all but their prey! E. MOSSY ROSES. Jim Chatfield reported that students in an OSU Agricultural Technical Institute class that he recently taught were thrilled by the handiwork of the tiny wasp (Diplolepsis rosae), which produces the MOSSY ROSE GALL on their namesake host. The galls are huge, spherical, hairy-looking structures that arise from year-old rose stems and measure as much as 2" in diameter. The galls appear on the stems in June or July. A close examination will reveal that the "hairs" are actually tendrils that are covered with short spikes. The tendrils are light green at first, but they quickly become much more colorful with the green becoming deep red accented by pink overtones. Eventually, the galls turn an unsightly grayish-brown and they may cling to the branches for 1-2 years before they degrade and disappear. Mossy rose galls provide a good lesson regarding gall-terminology. The galls are plurilocular, meaning that there are multiple chambers in each gall, as opposed to unilocular which means there is only one chamber per gall. And, the galls are unilarval, meaning that each chamber houses a single gall-making wasp larva as opposed to multilarval which means gall chambers house more than one immature gall-maker. The plurilocular, unilarval mossy rose galls may house 10-20 wasp larvae. The galls cause little harm to the overall health of rose plants; however, a heavy infestation may detract from plant aesthetics. Old galls remain evident long after they are vacated by the wasp. Since the wasp larvae spend the winter in the galls, pruning to remove the galls in the fall or very early spring provides an effective control by reducing wasp populations in rose plantings.
F. YES, IT'S A WHEEL BUG! The unusual yet incredible WHEEL BUG (Arilus cristatus) has been reported around Ohio. This strange looking insect has a creepy appearance, gray-brown with a long straw-like piercing beak and a wheel-like appendage on its thorax right behind the head. The back is flattened and soft appearing with the membranous wings laying on its back in an X pattern. People call the CWEPPDC and extension offices in an attempt to describe this weird looking bug that almost defies description. A member of the Order Hemiptera, the wheel bug is a true "bug" and one of the largest of the assassin bug species. True to its name, the wheel bug is highly beneficial in the garden as it will stealthily sneak up (looking like a dead leaf) to an insect and jab the hapless victim with its sharp beak. Holding the meal with its strong front legs, it will then suck the fluids from the insect then move on to find dinner. Although it is stated to attack insects with a soft exterior, it has been seen creeping up to Japanese beetles in rose and raspberry gardens and piercing them as well, in the crevice between the back of the thorax and the elytra. Go get 'em wheel bugs! As one can imagine a beak that can spear a hard shelled beetle could inflict a great amount of pain to human skin as well, so these insects should be handled with respect. Curtis reported another smaller species of assassin bug that stabbed a person's finger tip, when he reached into an outdoor oven mitt. The swelling and redness was so severe that the person went to the hospital. The prudent rule then is to appreciate their role in the garden and leave them alone to do their good work. G. IRIS BORERS AGAIN! Once again those who procrastinated treating their irises or chose to be organic need to check their irises now for the IRIS BORER (Macronoctua onusta) before the corms are destroyed! These perennial pests can be managed by digging and removing the corms each year in the fall and removing the borers and damaged corms, or by stopping them earlier in the year, but for large beds, all mechanical methods can be difficult. The iris borer moths lay eggs in the fall on debris and dead leaves. In early spring, the hatching larvae climb to new leaf tips and begin to mine down the leaves. Careful examination will reveal brown steaks in the leaves from the tip headed toward the crown. At this point, one can squeeze the brown tunnels and crush the small caterpillar. Another opportunity occurs when irises are finished blooming and leaves begin to senesce early. This should alert iris growers to look for the borers near the base and crush them immediately. At this point, the 2" long pinkish beige caterpillars have tunneled into the corms causing a brown, mushy rotted mess. If not controlled, the villains could destroy a large percentage of the irises. Once finished feeding, the caterpillars pupate in the soil and emerge in late summer, early fall as moths. Not a striking moth, they have dark purple-brown mottled forewings and yellowish hind wings. Their wing span is about 2". They may be seen at lights at night. To manage this pest, remove all dead and dying leaves and corms in early fall to remove egg laying sites. Monitor the iris leaves in the spring and remove any dead tissue that may still be present before the eggs hatch (late April-early May). If the iris borer has been problematic in the past, consider spraying the leaves with acephate or spinosad when the leaves are 5-6" tall, before they have mined into the leaves. The newer systemic insecticides would also be effective if drenched in early spring. H. RIDE 'EM COWBOY! HORSE FLIES BIG ENOUGH TO RIDE. Curtis Young reported that large horse flies have been attacking his car while driving in the country. These large horse flies typically emerge in mid- to late summer. The females of the horse fly species require a blood meal for nutrients needed to manufacture eggs. To collect the needed blood meal, the female flies search for and attack large warm-blooded mammals which include cattle, horses, mules, hogs, dogs, deer, and even humans. Outdoors enthusiasts and workers may find themselves falling victim to these hungry females. When she finds a host, she uses her sharp mandibles to slash a wound in the skin, injects an anticoagulant, and laps up the free-flowing blood. The bite is extremely painful. Horse flies are adept at locating warm-blooded animals, including people near swimming pools, streams, ponds, marshy areas and in the woods. According to Missouri University entomologists, the flies apparently are sensitive to parts of the electromagnetic spectrum--their sight may be like "thermal vision" cameras used to detect heat leaks in houses. They are also attracted to large moving objects which give off heat, like cars and trucks, thus resulting in Curtis's report of his car being attacked (one can hear them bouncing off of the car when they catch up to the car at stop signs). One species that is common in Ohio is Tabanus sulcifrons. This mostly brown horse fly is about 3/4-1" in length with cloudy brown wings, large compound eyes marked with bands of fluorescent green, and ferocious beak-like mouth parts that the fly uses to puncture its host to acquire its blood meal. Is there anything that can be done to deter these critters from biting? Not much! Suggestions include: avoid areas where horse flies (and deer flies) are most active; since the horse flies are active during the day, stay inside during daylight hours (this is not very practical when we have so many activities outside during the day to attend); stay alert while outside because unlike most other flies, the horse fly's flight is nearly silent, and they are known for landing stealthily on exposed skin then delivering a painful bite (those of us with bald heads are exceptionally vulnerable to attack from behind); wear light colored clothing (less attractive than dark colors) when outdoors to help reduce the annoyance from biting flies; in extreme cases, hats with mesh face and neck veils and neckerchiefs may add some protection; and use an insect repellent containing DEET. A unique device is the Tred-not Deer Fly Patch, which is a non-chemical sticky patch for controlling horse and deer flies. Some testers have reported good results from these odorless, non-chemical, adhesive patches. The patches are 3" wide by 6" long, and are worn on the back of a baseball cap to trap and hold biting deer flies. This might be the salvation for us baldies!
6. DISEASE DIGEST. A. CUCUMBERS ARE GOING DOWNY. Erik Draper reported DOWNY MILDEW is turning most cucumber leaves brown in Geauga County. This foliar fungus, Pseudoperonospora cubensis, rapidly infects and kills the leaves of plants in the Cucurbitaceae family. For most gardeners, this unfortunately means both the delicious cantaloupes and watermelons are at risk, as well as cucumbers, squash, and pumpkins. Of all of the cucurbit crops, cucumbers are the most susceptible to this disease. The next most susceptible vine crop after cucumber is cantaloupe, followed by pumpkin and other squashes and least susceptible is watermelon. The rapid death of the protective foliage exposes all fruit to direct sunlight, resulting in sunscald and severely reducing the quality of the remaining fruit. On cucumbers, downy mildew is easily identified by its unique checkerboard-like appearance of yellow and green on older leaves. The leaf infections cause a rapid chlorosis of areas seemingly restricted by leaf veins, resulting in angular lesions that are sharply defined. At first, just the leaf blade yellows, turns brown and appears to roll upward, while the remaining leaf petiole and the vine remain untouched and green. Eventually, the entire plant collapses due to the rapid loss of the leaves. In moist, humid conditions, on the underside of yellow leaf infections, there may appear a fungal layer of white to purplish to almost black in color. This foliar disease is very difficult to control even with fungicides. Unfortunately for homeowners, when downy mildew symptoms are easily recognized on the plants, it is usually too late to do anything about this disease. However, for commercial growers, if symptoms are detected early, using specific fungicides makes it possible to delay the plant's demise long enough to get the crop picked. Commercial fungicide recommendations for Ohio can be found at: [ http://vegnet.osu.edu/news/currentvn1809.htm ]. B. HOSTA VIRUS X (HVX) IS AGAIN DIAGNOSED. As in the past couple of years, a hosta submitted to the CWEPPDC was diagnosed as being infected with HVX. This virus produces symptoms of mosaic (chlorophyll-clear areas) and can lead to leaf desiccation and death in some hosta cultivars. There are three possible responses across hosta cultivars to HVX: 1) Susceptible to infection, with symptoms of varying degrees of severity; 2) Susceptible but showing no visual symptoms (tolerant); and 3) Immune to infection with no symptoms. Because plants can be tolerant, or asymptomatic when purchased, but develop symptoms weeks, months or years later, HVX is often is undiagnosed and many infected plants are sold. Diagnosis is further complicated because of the variety of symptoms exhibited by different varieties. Unfortunately, the virus is the most commonly occurring virus of hostas (Hosta spp.) in the United States, and its appearance seems to be increasing. This is perhaps due to several factors, including: 1) While, this disease is only mechanically transmitted by sap-to-sap contact between infected and healthy plants, many … or most … individuals who use tools to propagate this plant by division or to deadhead it fail to sterilize their tools. 2) As noted above, some varieties are tolerant and show no visible symptoms or be susceptible but not show symptoms for an extended period of time but be a source of infection to susceptible varieties. 3) Many home growers freely share their plants with friends and neighbors after division. That is, obviously, not a good thing. Also remember that no plants can be sold without a license and inspection by the ODA. For further information on this disease, including a chart of susceptible, tolerant, and immune hosta varieties, refer to "About hosta virus X," Michigan State University "Landscape Alert," Vol. 20, No. 16, August 26, 2005, at: [ http://www.ipm.msu.edu/CAT05_land/L08-26-05txt.htm ] and University of Minnesota "Yard and Garden Line News," Vol. 7 No. 8, June 1, 2005, at: [ http://www.extension.umn.edu/yardandgarden/YGLNews/YGLN-June0105.html#x ]. Excellent photos of HVX are available at: [ http://hostalibrary.org/ ].
7. TURF TIPS. A. CHINCH BUGS ARISE. Dave Shetlar reported that second generation HAIRY CHINCH BUGS (Blissus leucopterus) are active in turfgrass in central and southern Ohio; however, cool July temperatures coupled with consistent rainfall may be masking damage symptoms. Chinch bug damage usually appears as browned turf occurring in irregular patterns. The symptoms may be mistaken for high temperature dormancy, drought stress, or even certain turfgrass diseases. Chinch bug infestations cannot be identified through drive-by diagnostics. A proper identification requires an up-close and personal inspection on bended knee. Parting the grass will reveal the chinch bug adults and nymphs darting about among the turfgrass stems. If the grass is becoming off-colored, look closely at the exact color. Chinch bugs inject toxins into stems as they feed causing the blades to first turn a purplish color rather than the straw-brown color associated with drought stress. Chinch bug management strategies may include short-term suppression using insecticide applications, or long-term suppression through plant selection. Effective curative insecticides include: bifenthrin (e.g. Talstar); lambda-cyhalothrin (e.g. Scimitar); and deltamethrin (e.g. DeltaGard). For clients who desire a more "organic" approach, university research studies have shown that azadirachtin (e.g. Azatrol) provides about 80% control with one application and nearly 100% control with two applications made 10-14 days apart. Lawns with a long history of chinch bug outbreaks are good candidates for using turfgrass selection to suppress chinch bug populations. Certain cultivars of turf-type tall fescue and perennial ryegrass are known to harbor endophytic fungi. These fungi reside between plant cells within the turfgrass blades (= endo) where they enjoy a symbiotic relationship with the turfgrass plants. The fungi live off waste products exuded by plant cells. In return, the fungi protect turf plants by producing alkaloid compounds that are toxic to top-feeding insects, including chinch bugs. Over-seeding with "endophyte enhanced" turfgrass cultivars will provide a long-term solution to chinch bug problems. B. BROWN PATCH APPEARS. Joe Boggs reported that despite southwest Ohio experiencing the coolest July on record, brown patch caused by the fungus Rhizoctonia solani has started to appear on tall fescue in that part of the state. Infections are very light and occurring on lawns with a previous history of brown patch. Symptoms of brown patch vary greatly depending upon turf species, mowing height, soil, and environmental conditions. In high cut lawns, affected areas appear as large irregularly shaped circles 2-3' in diameter, or as a general thinning of turfgrass. Leaf lesions are irregularly shaped with grayish-brown tissue bounded by dark brown margins. Dollar spot produces similar leaf symptoms; however the lesions are usually tan in color and become hourglass-shaped as they expand across the width of the blade. The brown patch fungus occasionally produces white mycelium growth in the turfgrass canopy that may be mistaken for the mycelium of dollar spot or pythium blight. Brown patch can be managed culturally by employing good water management practices and by avoiding over-applications of nitrogen, particularly during warm, wet weather. Keeping foliage dry and enhancing soil drainage are the most important practices to reduce disease pressure. Irrigation should only be used during the early morning hours if possible. This allows moisture in the canopy to evaporate before high afternoon temperatures that support disease development occur. Maintaining a proper mowing schedule will also enhance drying of the foliage by improving light penetration and air circulation. All cool-season turfgrass species are susceptible to brown patch; however, Kentucky bluegrass is generally less susceptible than ryegrasses or tall fescues. Moderately resistant cultivars of perennial ryegrass, Kentucky bluegrass, and tall fescue are available. Over-seeding with cultivars that have some resistance to brown patch should be considered for lawns with a consistent history of the disease. Check the National Turfgrass Evaluation Program for information on cultivar susceptibility by visiting the following web address: [ http://www.ntep.org/ ]. C. SEEDLING OR OVERSEEDING THE LAWN THIS FALL. Gary Gao received a phone call about lawn seeding. The best time to seed a lawn in northern Ohio is between August 15 and September 15. In central and southern Ohio, the entire month of September is acceptable. Lawns seeded later in the fall may fail because the seedling turf has insufficient growth to survive the winter. Site Preparation: Many lawns are poor because the site was not prepared properly before establishment. Undesirable perennial grasses such as quackgrass, tall fescue, bentgrass, Timothy, and orchardgrass should be controlled before grading the lawn. Roundup (glyphosate) applied to growing grass will eliminate undesirable perennial grasses. Two applications spaced at 4-8 weeks may be necessary for deep rooted perennials. Glyphosate moves or translocates downward in grasses to kill underground plant parts like quackgrass rhizomes. Follow the directions on the label for application rates. A waiting period of 7 days after glyphosate application is necessary before tilling or sod disturbance. Grade the lawn so that good surface drainage is provided. Avoid steep slopes when possible. They result in many establishment and maintenance problems. The desired result in final site preparation is a firm soil without depressions or rough areas. Seeding: Sow seed evenly with a spreader. Plan to go over the area to be seeded twice, preferably in a different direction each time. With a low seeding rate, it is easier to get good distribution if something is added to the seed to make more bulk. Several materials such as sand or corn meal may be used. Starter fertilizer should be applied just prior to or after seeding. The soil should be raked lightly to cover the seed with 0.1-0.3" of soil. If some seed can still be seen after raking, they have not been covered too deeply. Apply a mulch after seeding to ensure optimum moisture conditions and reduce erosion. Straw applied in a thin layer is a very satisfactory mulch. Straw spread uniformly at 50-80 lbs (1‑2 bales) over 1,000 sq. ft. of seeded area is about the proper rate. When the job is finished there should be half soil and half straw when looking directly down on it. Watering, application of starter fertilizer and proper care after seedling are very important too. Existing lawns can be over-seeded with a slice/slit seeder. This is a tool where seeds are dropped into the grooves cut out by a set of round and rotating blades mounted on the bottom of the machine. Many tool rental or home improvement places have slit/slice seeders available for rental.
8. INDUSTRY INSIGHTS. A. ASIAN LONGHORNED BEETLE BYGL VISIT. BYGLers Jim Chatfield, Erik Draper, and Joe Boggs reported on visiting the sobering Asian longhorned beetle (ALB) (Anoplophora glabripennis; family Cerambycidae) infestation in Worcester, MA, last Wednesday on their return trip from speaking at the 2009 ISA Conference in Providence, RI. ALB was discovered in Worcester in August, 2008; however, it is suspected that the infestation is at least 5-6 yrs. old. The travelers met with members of the ALB Incident Command Team which includes United States Department of Agriculture, Animal and Plant Health Inspection Service (USDA APHIS) personnel and Massachusetts State Inspectors. The reason for the visit was to learn first-hand the diagnostic features of ALB, to view the impacts that ALB infestations and eradication efforts have on communities, and to see state and federal efforts to eliminate this non-native pest from the U.S. The group toured a number of ALB infestation sites located within the 64 sq. mile USDA APHIS ALB regulated area. The regulated area includes all of Worcester as well as parts of West Boylston and Shrewsbury [ http://www.ci.worcester.ma.us/cmo/pdf/ALBRegulatedArea.pdf ]. The entire regulated area is not infested; indeed the Command Team is currently conducting surveys to discover and delineate ALB infestations. Once found, infested trees are cut down and destroyed. Thus far, over 25,000 trees have been destroyed in an effort to eradicate the beetle. As its name indicates, ALB is native to Asia and is considered a serious pest in China. It is well known that the beetle is capable of hitch-hiking across the globe in wood packing material (e.g. infested pallets). ALB was first discovered in North America in Brooklyn, NY, in 1996. Subsequently, other infestations were soon discovered in other parts of New York City, in several nearby New Jersey suburbs, and on Long Island. In 1998, ALB was discovered in and around Chicago, IL, and in Toronto, Ontario. The Chicago infestations have been declared eradicated while work continues on eradicating the other infestations. The BYGLers noted that the impact on Worcester of the ALB infestations and eradication efforts can already be described as devastating. The group visited several previously tree-lined streets that are now almost devoid of trees; a scene that's eerily similar to the loss of ash trees to emerald ash borer (EAB) (Agrilus planipennis) in Toledo, OH. However, ALB has a much wider host range compared to EAB. Trees that are preferred by ALB include all species of maples (e.g. sugar, silver, red, Norway, box elder) as well as birches, elms, willows, horsechestnuts and buckeyes (the tree, not the travelers!). Trees that may be hosts to ALB, but are rarely attacked include: ashes, European mountainash, hackberry, London planetree, mimosa, and poplars. ALB is a large, striking looking beetle with very few look-a-likes found in North America. Indeed, many of the North American infestations, including the Worcester infestation, were discovered by people finding beetles rather than diagnosing the tree mortality caused by the beetles. Adults measure 1-1 1/2" in length. They are dark blue to bluish-black and covered with around 40 irregularly shaped and sized white dots. One of the Chinese common names for the beetle translates to the descriptively named "starry night beetle." As with most Cerembycids, ALB has exceptionally long antennae which are responsible for the common name. The antennae have alternating black and white bands. ALB adults emerge from July to October. Their circular emergence holes are around 3/8-1/2" in diameter. Although the beetles are capable of flying several hundred yards in search of a suitable host, they prefer to remain close to the tree from which they developed in order to re-infest the tree if it will support another generation. After mating, ALB adult females chew oblong-shaped 3/8" wide oviposition pits through the bark and phloem exposing the xylem (white wood). A single egg is deposited into each pit; the females are capable of laying 35-90 eggs during her lifetime. The oviposition pits and adult exit holes, if found on living branches and stems, are strong diagnostic indicators for an ALB infestation. Cerembycid larvae are commonly referred to as "roundheaded borers," and ALB larvae look like typical cerembycid larvae. The segments towards the front of the fleshy, thin-skinned, yellowish-white larvae are larger in diameter than the rest of the segments. This makes the larvae look like they have round heads and tapering bodies. ALB larvae develop through three instar stages. First and second instar larvae tunnel through and feed on phloem tissue. Their feeding activity produces weeping canker-like symptoms on the bark. Third instar larvae bore deep into the white wood. The wood boring activity of the final instar larvae produces two diagnostic indicators of an ALB infestation. The first is course, white, sawdust-like frass that is exuded from the infestation sites. The second is a branch and stem breakage. In fact, one of the Worcester infestations was discovered by USDA APHIS personnel examining the ends of branches broken in an ice storm. While an established ALB infestation has not yet been discovered in Ohio, the history of this destructive non-native pest speaks to the need to be ever vigilant. As the BYGLer travelers observed first-hand, early detection is critical to stemming the beetle's potential impact on urban communities.
9. COMING ATTRACTIONS. A. SOUTHWEST OHIO BYGLIVE! The 5th 2009 Southwest Ohio BYGLive! Diagnostic Walk-About will be held on Monday, August 10, at the Cincinnati Zoo and Botanical Garden, 3400 Vine St., Cincinnati, 45220 [use new entrance off Vine Street]. Join Joe Boggs, Dave Dyke, and our host Steve Foltz (Director of Horticulture) to walk-about from 12:00-3:00 pm. to look at plants, plant pests, plant diseases, animals (e.g. Joe Boggs), and other points of considerable interest. Two points of particular interest will be the annual plant trials/demonstration gardens sponsored by OSU Extension, Hamilton County, the Cincinnati Flower Growers Association, and the Zoo, and the Zoo's storm water mitigation installations (rain gardens, rooftop garden, permeable pavers, etc.). The Zoo's goal is to achieve zero storm water runoff from the grounds. Don't miss this hands-on training for Green Industry professionals. ISA Certified Arborist CEU's will be available, and this training event counts for ONLA Ohio Certified Nursery Technician credits. For more information, contact Joe Boggs at: 513-946-8993. B. 42nd ANNUAL NGLCO SUMMER FIELD DAY. The Nursery Growers of Lake County Ohio (NGLCO) annual summer field day will be this coming Tuesday, August 11, 2009 from 9a.m.-4p.m. The event will be hosted by North Coast Perennials, Inc., which is located at 3754 Dayton Road, Madison, Ohio. As always, there will be plenty of things to see and do. Spend the day reviewing the exhibitor displays, equipment demonstrations, and live entertainment. The home-cooked lunch will be served between 11:30 a.m.-1:30 p.m. For more information on attending or exhibiting call 440-241-7969. C. 2009 OSU/OTF TURFGRASS RESEARCH FIELD DAY. The 2009 Turfgrass Research Field Day is next Wednesday, August 12th at the Ohio Turfgrass Foundation (OTF) Research and Education facility, 2551 Carmack Road (off Kenny Road), Columbus, Ohio. As usual, Golf Course Superintendents, grounds and athletic field managers, lawn care operators, sod producers and landscape professionals will learn the latest research on golf course, lawn care and sports fields turfgrass. Come out and discover what's new in turfgrass research at The Ohio State University. Registration includes lunch. *Golf Course- ant and disease control on golf course turfgrass, summer disease, morphology changes in shaded conditions, herbicide tenacity, and dollar spot genetics. *Lawn Care and Sports Turf- Seeding to play in 4 weeks; Bermudagrass establishment on sand rootzones, new broadleaf and grass herbicide trials, turfgrass evaluation in shaded conditions, and compost trials. Afternoon Program (1:00-2:00 p.m.) Using Systemic Insecticides for Ornamental Insect Control (Category 6A, 1 hr.) Managing the Top 10 Tree & Shrub Diseases (Category 6A, 1 hr.) For more information and registration materials call OTF at (888) 683-3445 or visit [ http://www.OhioTurfgrass.org ]. Registration is limited. D. OHIO LAWN CARE OUTDOOR SUMMER SEMINAR is Thursday August 13, 2009 at the OSU Research & Education Facility in the Waterman Farm complex, 2551 Carmack Road, Columbus, OH. Everyone involved in lawn care and landscape maintenance is invited to attend this informative event. Registration will be limited to the first 200 participants. The seminar will feature presentations at turfgrass research plots on various topics including: *Turf Disease and Problem Solving *Improving Poor Soils with Organic and Synthetic Fertilizers *New Herbicide Options for Turfgrass (Category 8, .5 hrs.) *Turfgrass Insect Diagnosis and Management (Category 8, .5 hrs.) *Emerald Ash Borer/Tree & Shrub Diagnostics *Postemergence Annual Grassy Weed Control Options & Current Research (Category 8, .5 hrs.) *Equipment Showcase Participants will have the opportunity to demo lawn maintenance equipment from several leading manufacturers. For more information call Ohio Lawn Care Association at (800) 510-5296 or visit our website at: [ http://www.OhioLawnCare.org ]. E. PESTICIDE APPLICATOR TRAINING OFFERED. Trained Serviceperson and New Applicator Commercial Schools are planned for August 26, 2009 and September 30, 2009. These sessions will be taught at the Ohio Department of Agriculture (ODA) in Reynoldsburg, Ohio. For additional information on these schools, and other educational opportunities, check out the Pesticide Education website at [ http://pested.osu.edu ]. F. WOOD DESTROYING INSECT INSPECTION TRAINING. Mark your calendars for training on September 16, 2009. This training will be held at ODA in Reynoldsburg. Recertification credit will also be available in Core, 10b and 12. For additional information, check out [ http://pested.osu.edu ]. G. DATES SET FOR COMMERCIAL APPLICATOR RECERTIFICATION CONFERENCES. The following dates have been set for recertification conferences this winter. Mark your calendars now!
10. BYGLOSOPHY. "It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure." - Albert Einstein
Where trade names are used, no discrimination is intended and no endorsement by Ohio State University Extension is implied. Although every attempt is made to produce information that is complete, timely, and accurate, the pesticide user bears responsibility of consulting the pesticide label and adhering to those directions. OSU Extension embraces human diversity and is committed to ensuring that all educational programs conducted by Ohio State University Extension are available to clientele on a nondiscriminatory basis without regard to race, color, age, gender identity, or expression, disability, religion, sexual orientation, national origin, or Vietnam-era veteran status. Keith L. Smith, Associate Vice President for Ag. Adm. and Director, OSU Extension, TDD No. 800-589-8292 (Ohio only) or 614-292-1868.
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| Last Updated on Thursday, 06 August 2009 18:23 |
