NEW INSECTICIDES FOR ARMYWORM CONTROL IN PASTURES
By Lee Townsend

(Frankfort) The U.S. Environmental Protection Agency has granted special registration for two insecticides to combat armyworms in pastures and hayfields in Kentucky, the Ky Department of Agriculture has announced.

The insecticides are Pounce 3.2 EC (FMC Corp.) and Confirm 2F (Rhom and Haas Co.). Both are Restricted Use pesticides. Cattle can be present during application, if necessary, when Pounce is applied and they may graze fields after treatment. However, pastures sprayed with Pounce cannot be cut for hay during the remainder of the season. Pastures sprayed with Confirm 2F can be harvested for hay after a14-day wait.

Applicators must have a copy of the appropriate state (24-c) label for Pounce or the Crisis Exemption label (Section 18) for Confirm. These are available from the pesticide dealer when the products are purchased.

CURRENT BLUE MOLD STATUS
By William Nesmith

Moderate to damaging levels of blue mold are present in many communities in the region. Strongest activity is in northern Kentucky in a 30- mile wide band along the Ohio River from near Owensboro to near Maysville, and in an 80-mile wide ban in eastern Kentucky running from near Maysville southeast to near Jackson, being strongest in the Kentucky River (main , Elkhorn Creek, Eagle Creek), Licking River, and Red River valleys. In addition, isolated pockets of strong activity were being reported over the weekend in Warren, Simpson, and Logan counties. Most of this strong activity is the result of the weather events of July 8 and 9, and that event was behind my reasons for maintaining the warnings/watches for the following extension areas: Southern Ohio, western West Virginia, Green River, Louisville, Northern Kentucky, Licking River, Northeast Kentucky, Bluegrass, Ft Harrod, Quicksand, and Wilderness Trail. In addition, on Friday I returned the Lake Cumberland, Southern Indiana, and Southeastern Indiana to the watch status and today will place all the Mammoth Cave, Lincoln Trial, and Pennyrile areas to a watch, but several counties in those areas are already under warnings.

County Extension Agents report considerable grower apathy about blue mold control. Most growers lack access to the equipment required to effectively use foliar fungicides and they are slow to accept Actigard because of cost and the phytotoxicity issues. In part, however, this apathy is also resulting from the amount of carry-over crop on many farms from last year. Many growers feel they can afford to take the damage dished out by this years outbreaks and are just letting it run. Growers not in that situation, however, need to realize such farms could generate a lot of nearby inoculum.

Some dealers are reporting difficulty in obtaining adequate supplies of Acrobat MZ. Remember that Acrobat 50 W is now labeled under a federal label, but it must be tank mixed with another labeled fungicide. We have tank mixed Acrobat 50 W and Actigard 50 W and applied them for full coverage following the Acrobat 50W directions for application and obtained successful control. However, there was limited improvement in control over Actigard alone, if this tank mix was applied with a broadcast boom to the tops of the plant.

For the latest blue mold status and other tobacco disease information, check the KY Blue Mold Warning System.
http://www.uky.edu/Agriculture/kpn/kyblue/kyblue.htm

SECOND GENERATION CORN BORERS ACTIVE
By Ric Bessin

European
Pepper producers need to be monitoring and managing second generation European corn borer. The larvae of this generation are active now across the entire state. Those in the western half being about 7 to 10 days ahead of those in central KY. Keep in mind that sprays are preventative and need to be applied prior to egg hatch with peppers. As little as 12 to 24 hours are needed for the larvae to tunnel into the pepper fruit. Producers picking peppers during this time will need to carefully select insecticides to control European corn borer that have preharvest intervals that are compatible with picking schedules. Preharvest intervals can range from 0 to 7 days for the commonly used insecticides on peppers.

Southwestern
Southwestern corn borer moth flight from emerging first generation corn borers is beginning to increase in western Kentucky. This means that second generation egg laying is just around the corner. The greatest threat from SWCB this year will be to late planted fields, as those are the fields that generally are harvested last. The longer that harvest is delayed, the more time that these corn borers have to girdle the base of the stalks. What we have observed in the past is that the majority of girdling begins to occur in September, with most complete near the end of the month.

In early to mid August, corn producers should identify the fields with the worst corn borer infestations. These fields should be harvested as early as practical in order to avoid lodging. Everything else being equal, fields with less of a corn borer infestation can be harvested after the heavily fields have been shelled. Fields with low corn borer infestations are likely to loss less corn to harvesting losses.

For corn producers that have the ability to treat late season corn borers, we used 25% plants infested with larvae that are still in places accessible to insecticides as the threshold for southwestern corn borer. For European corn borer, we use the threshold provided in ENT-49, Corn borers in corn. With late season ECB, only 2.7% in preventable yield loss will occur by treating a 40% infestation, while 6.7 % preventable yield loss will be saved when treating an 80% infestation. As always, only ECB or SWCB that have not bored into the stalk and are still exposed to sprays can be controlled. Timing is very important.

For more information about corn pests, visit "Insect Management Recommendations".

CAUSE OF SOYBEAN "UNTHRIFTINESS"
By Don Hershman

Over the past month, the Plant Disease Diagnostic Laboratory at Princeton has received numerous samples of "unthrifty" soybean plants. Many times rather large areas within a field are involved and in some cases, the majority of a field has been impacted in some way. This situation has resulted in my receiving many phone calls and making farm visits to try to determine the cause of poor soybean growth. Many of the affected fields are in the Green River Area, but other areas of the state also have problem fields.

In all the instances I have seen, the unthrifty plants exhibit abnormal roots and, consequently, the plant foliage is yellowing and/or scorched and plants have stunted growth patterns. The abnormal roots show a variety of "symptoms." In some instances, the lower taproot has died and plants have responded by generating new roots in the upper taproot region. In other cases, the root system has a "J" or "L" appearance and overall root biomass is reduced. Oftentimes, reduced root systems have odd nodulation patterns or reduced nodulation. In some fields, the root system has a "bottle brush" appearance in which plants develop a short stubby root system in the vicinity of the upper taproot. In other cases, the overall root system is reduced in size and roots have a thickened, stubby appearance. In almost all cases there are some discolored roots throughout the root system. In addition, reddish brown cankers at the soil line are frequently evident; plant stems in this area are often swollen, fissured and may be brittle.

In the majority of the fields, I have ruled out a plant pathogen as being the primary source of the problem. I have regularly observed Pythium spp. and Rhizoctonia in discolored roots, and various species of Fusarium have been isolated. Some soybean cyst nematode (SCN) is involved, but most affected root systems have been minimally impacted by SCN. In addition, it is common to find Rhizoctonia associated with lower stem cankers, but this is not always the case.

After discussions with agronomists, we have concluded that the root problems appeared to be related to a wide-ranging set of adverse soil situations/conditions which have existed this spring in many fields. Furthermore, that these adversities (in some cases multiple adverse conditions in a single field) have significantly stressed the root systems of plants. It is my opinion that the plant pathogens we are seeing are secondary in nature and have infected stressed, dying and dead roots. Having said that, I feel certain that the fungi are having a negative impact on root system recovery. Nonetheless, we are talking about plant pathogenic fungi that are present in all agricultural soils and are opportunists. Thus, it is unlikely that anything could have been done to prevent the infections unless the original stress could have been avoided in the first place.

Now, what are the adverse conditions I am referring to- Well, it is a "laundry list" of sorts:

• Soil compaction, hard pans, adverse soil pH, poor soil drainage, seedling development problems associated with no-tilling under marginal soil conditions, herbicide carryover from previous growing season, herbicide damage from spring applications, moisture extremes at various times during the season - even in the same field, soil fertility imbalances, nutrient excesses and deficiencies, planting marginal quality seed, and probably many others.

I feel certain that dryer than normal soil conditions this spring have exacerbated many of the above factors and this has led to even greater problems. Many problem fields have started to recover now that adequate moisture exists in most areas (at least for now). I expect plant recovery to continue unless late?season stress or pests become a significant limiting factor.

DOWNY MILDEW ALERT FOR CUCURBIT CROPS
By William Nesmith

Once present in Kentucky, downy mildew will continue until frost as long as sufficient leaf moisture is present from dew or fog. Without timely and well?applied controls, downy mildew can quickly destroy most cucurbit crops, including cucumber, cushaw, muskmelon, squash (summer and winter types), pumpkin, and watermelon. Downy mildew levels vary greatly from year to year in Kentucky, and greatest damage occurs when it arrives early, prior to August 15.

Symptoms vary by crop, but it usually starts as tiny yellow spots on the upper leaf surfaces of older leaves that quickly expand to blight the entire leaf. Dead leaves result in poor fruit development, plus it exposes the fruit to sun scald. Under wet conditions, the fungus usually can be found sporulating on the underside of the lesions, as a downy, fuzzy growth that is clear, white, gray or blue in color. It is not as easily seen with the unaided eye as is tobacco blue mold.

The disease can be very damaging in prolonged foggy or humid periods, plus it can strike very rapidly. Growers following our guidelines should already be following a regular preventive, and well? applied fungicide spray program for control of gummy stem blight, anthracnose, or Alternaria leaf spot (depending on the crop) but with downy mildew around, they will also need to include a specific downy? mildewcide in the control. See ID? 36, for commercial vegetable control guidelines for each crop, which is also available at the following website address http://www.ca.uky.edu/agc/pubs/id/id36/id36.h tm. Those planting fall cucurbit plantings should consider downy mildew resistant varieties where available.

Connections to the Downy Mildew Forecast are available at the following website address http://www.uky.edu/Agriculture/kpn/kyblue/do wny.htm

DISEASES OF WOODY ORNAMENTALS AND TREES IN NURSERIES ? A NEW REFERENCE BOOK
By John Hartman

After several years of work by almost ninety contributing authors, APS press has recently released a new book entitled Diseases of Woody Ornamental Plants and Trees in Nurseries edited by Ronald K. Jones and D. Michael Benson. Plant pathologists from throughout the U.S., including two authors from Kentucky contributed to this book.

The book covers diagnosis and control of diseases of more than 65 ornamental crops (shrubs, ground covers and shade trees) grown in nurseries throughout the United States. A summary of timely control measures is given for each disease in this book. These control strategies provide an in?depth guide to integrated disease management including, cultural control, sanitation, disease resistance, fungicides and bactericides as well as information on control of various pathogen groups. Many of the crop chapters include information on cultivar resistance to plant disease. The role of recycled water in disease development and ways to manage pathogens in recycled irrigation water is also covered. Readers are helped further by 160 color plates illustrating disease symptoms, tissue culture techniques to eliminate pathogens from propagation stock, a state-by-state list of disease occurrences to make you aware of local problems, and an explanation of the role of plant diagnostic clinics in assisting nurseries in disease diagnosis.

Diseases of Woody Ornamentals and Trees in Nurseries presents state-of-the-art information on important nursery crop issues. It explains the latest horticultural practices in relation to the prevention, diagnosis and control of diseases on nursery stock and may be used by anyone involved with the care of these valuable plants including: nursery professionals, extension specialists, county agents, growers, tree?care professionals, master gardeners, researchers, educators, and regulatory personnel.

Table of Contents: USDA Plant Hardiness Zone Map; Plant Disease Development; Abiotic Cause of Disease; Abiotic Diseases of Woody Ornamentals; Biotic Cause of Disease; Fungi; Bacteria; Nematodes; Viruses; Phytoplasmas; Botrytis Blight (Gray Mold); Crown Gall; Cylindrocladium Diseases; Damping? Off of Seeds and Seedlings and Cutting Rot; Nematode Diseases; Phytophthora Root Rot and Dieback; Powdery Mildew; Diseases Caused by Pseudomonas syringae; Rhizoctonia Web Blight; Southern Blight (Sclerotium rolfsii); Verticillium Wilt (Verticillium dahliae); Diseases of Specific Crops; Arborvitae; Ash; Aucuba (Japanese Laurel); Azalea; Barberry; Birch; Boxwood; Camellia; Cedrus; Cotoneaster; Crapemyrtle; Cryptomeria; Daphne; Dogwood; Eleagnus; Elm; English Ivy; Euonymus; Fatsia and Fatshedera; Fir; Flowering Crabapple; Flowering Pear ; Forsythia; Gardenia; Ginkgo; Hawthorn; Hibiscus; Holly; Honeylocust; Hydrangea; Indian Hawthorn; Ixora; Juniper; Leucothoe; Leyland Cypress; Ligustrum; Lilac; Linden; Lonicera (Honeysuckle); Magnolia; Maple; Mountain Laurel; Nandina (Heavenly Bamboo); Oleander; Osmanthus; Palm; Photinia; Pieris; Pine; Pittosporum; Podocarpus (Southern Yew); Poplar; Prunus; Pyracantha; Redbud; Rhododendron; Rose; Sourwood; Spirea; Sycamore and Planetree; Taxus; Ternstroemia; Tuliptree; Viburnum; Wax Myrtle (Bayberry); Disease Management; An Introduction to the Management of Infectious Plant Diseases In the Nursery; Integrated Disease Management in the Nursery; Sanitation: Plant Health from Start to Finish; Horticultural Practices to Reduce Disease Development; Control of Fungal Diseases; Control of Bacterial Diseases; Control of Viral Diseases; Control of Nematode Diseases; Fungicides for Ornamental Crops in the Nursery; Bactericides; Disease Management For Nurseries Using Recycling Irrigation Systems; Disease Resistance; Mycorrhiza Effects on Diseases; Biological Control of Woody Ornamental Diseases; Plant Problem Diagnosis and Plant Diagnostic Clinics; Tissue Culture of Woody Plants; Regulatory Control; Appendix; Diseases of Woody Ornamentals and Trees by State; and, Glossary.

Publication and ordering specifications: 2001; 8 1/2" x 11" softcover; 482 pages; 160 color photographs (est.) ISBN 0-89054-264-3; $89. This book may be ordered on-line or by calling toll-free 1-800-328-7560.

DAY LILY RUST FOUND IN KENTUCKY
By John Hartman

Day Lily rust disease was identified for the first time in Kentucky today. This disease is a real threat to this popular Kentucky garden plant grown by homeowners, nurserymen and others.

The specimen came from a Fayette County non- commercial daylily grower who buys plants from the south.

We are in the process of notifying USDA officials (through our USDA APHIS Kentucky Nursery Inspectors housed here at U.K.) as to what, if anything, needs to be done about the diseased plants to keep the disease from spreading.

Some of you may recall reading about this in a recent Kentucky Pest News article (July 2). Excerpts from that article follow.

Daylily rust was found for the first time in North America last year in Florida. Since then, it has been spread (mainly on infected nursery plant material) to several other states including Alabama, California, Georgia, Kansas, Louisiana, Minnesota, Mississippi, South Carolina, Tennessee and Texas. (...and now Kentucky)

The causal agent is Puccinia hemerocallidis, a rust fungus. The disease is identified by bright yellow or orange colored spots with raised pustules on the foliage of affected plants and by orange colored spores which emerge from the pustules. As symptoms progress, leaves turn yellow and dry up. The following web site (http://www.ncf.ca/~ah748/rust.html) shows good pictures of this and other daylily diseases and disorders.

It is believed that the disease will become a serious pest of daylilies. The disease is easily spread in the nursery trade because viable spores may be carried long distances on plants and propagative material not showing symptoms.

If daylily rust is suspected, immediately remove all infected foliage and burn or bury the clippings except to save a leaf or two to send to the County Extension Office; the agent will get them to our plant disease diagnostic laboratory. Most County Extension Agents will recognize rust disease and would be able to tell the homeowner immediately whether daylily rust is present, or if it is suspected. Following diseased foliage removal, sterilize tools with 70% alcohol, 10 % bleach, or lysol to prevent spread. Wash hands, gloves, or clothes afterwards, if necessary, to prevent spread to the rest of the garden. New foliage can be protected as it emerges with fungicides such as propaconizole (Banner Maxx), azoxystrobin (Heritage), flutolonil (Contrast), or myclobutanil (Systhane, Eagle). Because this is a new disease, there is no specific label of daylily rust. Be sure that the label indicates that the fungicide product used can be used on daylilies or on ornamentals generally in the nursery or landscape. Resistant cultivars have not yet been identified.

Agents, homeowners and nurserymen are urged to be on the lookout for this potentially serious disease of daylily.

...AND ALONG CAME A SPIDER
By Mike Potter

Numerous calls are received each year about spiders. Typically, the caller wants to know if the spider they've seen is dangerous, and what if anything should be done in terms of control.

Many different kinds of spiders live in and around buildings. Some, such as the house, cellar, and garden spiders, construct webs to help entrap their prey. Others, like the wolf spiders, are free-roaming and make no webs. The vast majority of spiders are harmless, and in fact are beneficial because they prey upon flies, crickets and other insects. They generally will not attempt to bite humans unless held or accidentally trapped. Moreover, the majority of spiders have fangs too small or weak to puncture human skin. Of the hundreds of species found in Kentucky, only the black widow and brown recluse are dangerous. Fortunately, both are relatively uncommon, and have markings which can be used to distinguish them from other non-threatening species.

Even though most spiders are harmless, few people are willing to tolerate them inside the home. Their unsightly webbing and fecal spots outweigh the beneficial aspects of spiders to most homeowners. This column provides practical tips on spider control for concerned clients.

General Control Measures (all species)
1. Routine, thorough house cleaning is the most effective way to eliminate spiders and discourage their return. A vacuum cleaner and broom are the householder's most useful tools for removing spiders, webs, and egg sacs. Egg sacs in particular should be removed since each may yield hundreds of new spiders.

2. Spiders prefer quiet, undisturbed areas such as closets, garages, basements, and attics. Reducing clutter in these areas makes them less attractive to spiders.

3. Large numbers of spiders often congregate outdoors around the perimeter of structures. Migration indoors can be reduced by moving firewood, building materials, and debris away from the foundation. Shrubs, vines and tree limbs should be clipped back from the side of the building. Maintaining a vegetation-free zone next to the house also lowers the moisture content of the foundation and siding, making them less attractive to termites, carpenter ants, rodents and decay.

4. Install tight-fitting window screens and door sweeps to exclude spiders and other insects. Inspect and clean behind window shutters, and inside the orifices of gas barbecue grills.

5. Consider installing yellow or sodium vapor light bulbs at outside entrances. These lights are less attractive than incandescent bulbs to night-flying insects which, in turn, attract spiders.

6. To further reduce spider entry from outdoors, insecticides can be applied as a "barrier treatment" around the base of the foundation. Pay particular attention to door thresholds, garage and crawl space entrances, and foundation vents. Sevin, Dursban, or any of the synthetic pyrethroids (e.g., Bayer Advanced Multi-Insect Killer (cyfluthrin), Spectracide Bug Stop (tralomethrin), Ortho Home Defense System (bifenthrin)) are effective, but may need to be reapplied periodically throughout the summer.

--Brown Recluse/Black Widow
Both of these spiders are potential health threats. They are timid, however, and will only bite in response to the threat of being injured. Most bites occur while putting on a shoe or piece of clothing in which a spider has hidden, or while unpacking boxes, sorting through clutter, etc.

The female black widow is about 1/2-inch long, shiny black and usually has a red hourglass mark on the underside of the abdomen. In some varieties the hourglass mark may be reduced to two separate spots. Most adult brown recluse spiders are about the size of a dime to a quarter with legs extended. Coloration ranges from tan to dark brown, with the abdomen often darker than the rest of the body. The feature that most readily distinguishes the brown recluse from many other harmless spiders is a somewhat darker violin-shaped marking on the top of the leg-bearing section of the body. The neck of the violin "silhouette" points toward the rear (abdomen) of the spider. Closer examination under magnification will reveal only three pairs of eyes toward the front of the head most other spiders have eight eyes. Although both the black widow and brown recluse have distinctive markings, a "spider is a spider" to most people. Concerned homeowners or victims of spider bites should be advised to bring the specimen in for confirmation.

Spider bites are difficult to diagnose, even by physicians. Black widow venom is a nerve toxin and its effects are rapid. The victim suffers painful rigidity of the abdomen and usually tightness of the chest. Victims should seek medical attention promptly. The bite of the brown recluse is usually painless until 3 to 8 hours later when it may become red, swollen and tender. Later the area around the bite site may develop into an ulcerous sore from ½ to 10 inches in diameter. Healing often requires a month or longer, and the victim may be left with a deep scar. Prompt medical attention can reduce the extent of ulceration and further complications. Not all brown recluse bites result in ulcerations and scarring.

The brown recluse may be found living indoors or outdoors. Black widows are more often encountered outdoors. Thorough inspection of cracks, corners, and other dark, undisturbed areas with a bright flashlight is an essential first step in determining the location and extent of infestation. Indoors, pay particular attention to basements, attics, crawl spaces, closets, under/behind beds and furniture, inside shoes, boxes of stored items, and between hanging clothing. Brown recluse spiders also may be found living above suspended ceilings, behind baseboards, and inside ductwork or floor/ceiling registers. Another way to detect infestations in these areas is to install glueboards or sticky traps. Designed to capture mice and cockroaches, these devices can be purchased at grocery or farm supply stores. Placed flush along walls and in corners, they are useful monitoring tools and will also capture large numbers of spiders.

Brown recluse and black widow spiders also live outdoors in barns, utility sheds, woodpiles, and underneath lumber, rocks, and accumulated debris. To avoid being bitten, wear work gloves when inspecting inside boxes or when moving stored items.

Each of the management tips (1-6) mentioned above for spiders in general are useful for the black widow and brown recluse. Removal of unnecessary clutter is especially helpful in making areas unattractive to these pests. Indoor infestations of brown recluse and black widow also warrant treatment with insecticides. Insecticides should be applied into areas where spiders are living, making an attempt to contact as many spiders and webs as possible with the treatment. Most household insecticides with spiders listed on the label will kill spiders provided the spider is treated directly. Spot treatment with synthetic pyrethroids such as those mentioned earlier are especially effective. In attics, storage sheds, and other inaccessible or cluttered areas, total-release foggers (e.g., Raid Max, containing cylathrin=cyfluthrin) will have a better chance of contacting spiders that are hidden.

Severe infestations of brown recluse or black widow spiders require specialized skills, persistence and equipment to eradicate. In these situations, it would be prudent to call a professional pest control operator.

DIAGNOSTIC LAB - HIGHLIGHTS
By Julie Beale and Paul Bachi

Field crop samples in the diagnostic lab last week included anthracnose, Phytophthora wilt and potash deficiency on soybean; black shank, soreshin, Fusarium stem rot, Rhizoctonia root rot, blue mold, frogeye, herbicide injury, tomato spotted wilt virus and tobacco ringspot virus on tobacco.

On fruit and vegetable samples, we have diagnosed double blossom, fire blight and psyllid damage on blackberry; black rot, downy mildew, tar spot and growth regulator injury on grape; powdery mildew and blister spot (Pseudomonas) on apple; Cytospora canker on plum; brown rot on peach; angular leaf spot and Rhizoctonia stem canker on bean; oedema on collard; anthracnose on cucumber; bacterial wilt on muskmelon; powdery mildew on pea; bacterial crown rot on rhubarb; and bacterial canker, early blight, tomato mosaic virus and tomato spotted wilt virus on tomato.

On ornamentals, we have seen rust on daylily (first report in Kentucky); corm rot (bacterial and Fusarium) on gladiolus; Cladosporium leaf blotch on peony; white rust on morning glory; anthracnose and Bipolaris leaf spot on ryegrass; necrotic ringspot on bluegrass; Cercospora leaf spot on ash; spot anthracnose and powdery mildew on dogwood; Botyrosphaeria dieback on rhododendron; and Pseudonectria canker/dieback on boxwood.

By Patty Lucas, University of Kentucky Research Center

Insect Trap Counts

To see recent moth trap counts, click here.

Lee Townsend
Extension Entomologist

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