2000 INSECT MANAGEMENT RECOMMENDATIONS FOR FIELD CROPS AND LIVESTOCK
By Lee Townsend

NEW ENTFACT PUBLICATIONS
By Ric Bessin

Several new Entfact publications are available. They can be found on the UK Entomology web page http://www.uky.edu/Agriculture/Entomology/enthp.htm. They are in both HTML and PDF format for use at county extension offices. These were issued during the summer and fall of 1999.

Entfact 127 Alfalfa weevil field sampling program
Entfact 128 Bt-corn refuges
Entfact 129 Lesser cornstalk borer
Entfact 130 Bt Corn: What it Is and How it Works
Entfact 216 Leafrollers
Entfact 218 Apple Bagging: Alternative Pest Management for Hobbyists
Entfact 315 Cabbage Webworm
Entfact 441 Insecticides for Control of White Grubs in Turf Grass
Entfact 442 Velvet Ants
Entfact 507 Lesser Mealworms and Litter Beetles
Entfact 508 Walk Through Fly Trap for Pastured Cattle
Entfact 509 Horn Flies and Cattle
Entfact 510 Face Flies and Pinkeye
Entfact 511 Horse Flies and Deer Flies
Entfact 642 Do-it-yourslef Termite Baits: Do They Work?
Entfact 643 Limitation of Home Insect Foggers ("Bug Bombs")
Entfact 644 Consumer Update: Termite baits
Entfact 645 Millipedes
Entfact 646 House Dust Mite

2000 IPM SCOUT TRAINING SCHOOL
By Patty Lucas

Mark your calendar now for the 2000 IPM Training School! Scheduled for March 15, the meeting will be held at the UK Research Center in Princeton. Registration will open at 8:30 AM with the meeting starting at 9:00AM.and ending at 3:30 PM.

The program will feature a new session this year. For the first hour participants can choose to attend a session on "Introduction to Scouting" or "Advanced Scouting". The "Introduction to Scouting" session will teach site selection and the basic techniques for scouting corn, soybeans, alfalfa and small grains. This session is designed for those who have never scouted a field .

"Advanced Scouting" session is designed for those who have attended previous IPM Training Schools and are experienced scouts. This session will not cover the basics of scouting, but topics such as Using DGPS for Scouting and Soil Sampling.

Pest identification will be a major part of the training school. Weed, insect and disease problems of corn, soybeans, small grains and alfalfa will be covered. An update of pest problems in Kentucky will also be discussed.

Advance registration is not needed and the meeting is open to the public free of charge. The program has applied for 5.5 CEU's for Certified Crop Advisors (2.0 Pest Management, 2.0 Crop Production and 1.5 Soil Fertility). For additional information contact Patty Lucas at 270 - 365-7541 extension 218 or plucas@ca.uky.edu.

CONSIDERATION FOR DISEASE CONTROL IN TOBACCO TRANSPLANT PRODUCTION SYSTEMS - 2000 CROP
By William Nesmith

An adequate supply of healthy disease-free transplants is an important first step to having a successful tobacco crop in 2000. Infectious diseases can be a limiting factor to successful transplant production. Inadequate transplant supplies can result from epidemics of blue mold, Pythium, Rhizoctonia, and bacterial blackleg. Furthermore, diseased transplants are prone to additional attacks in the field and they can serve as important sources of pathogen introduction to the field and community. During the 1990's, field epidemics of blue mold, black shank, Pythium blight, Rhizoctonia root rot/soreshin, and tomato spotted wilt were directly related to setting diseased transplants.

Tobacco transplant production in Kentucky occurs mainly in float systems (either in greenhouses or outside float beds) and in traditional ground beds. The potential for infectious diseases is especially high in the float systems, as currently operated, because of contamination from sloppy sanitation and predisposition of the seedlings from water-saturated root systems, excessive watering, poor ventilation/circulation, fertilization mistakes, crowded plantings, and frequent wounding of plants. Unfortunately, there are not legal options to eliminate diseases in transplants after infections have occurred.

Carefully growing your own transplants is the best assurance against bringing someone else's disease problem onto your farm. However, the tobacco industry is relying more and more on commercially produced transplants. In general, commercial producers often provide a better transplant, because the commercial firms are paying more attention to the details associated with disease control than are most tobacco farmers. The tobacco community needs to recognize the increased risk associated with introducing pathogens from outside the community and the increased potential for sharing of diseases from farm to farm resulting from the promiscuous nature of current seedling production.

Control of transplant diseases is achieved through aggressive sanitation measures, careful management of the production environment, controlling insect vectors, avoiding plant stress, and timely application of pesticides. Both the incidence and severity of diseases in seedling production can be greatly reduced through chemicals involved with fumigation, sanitation and preventive spray programs. Unfortunately, adequate labeled materials are not available for use in the greenhouse and float systems. Furthermore, many pesticide manufacturers have elected not to label their products for use in tobacco transplant production because of the product liability risks associated with fungicide resistance under such high disease potential.

In June 1998, the EPA re-stated its position concerning pesticide use in the greenhouse. That position is that labels must specifically cite the greenhouse and greenhouse-crop-stage as a site, if the product is to be used in greenhouse production systems. Also, EPA's Regional Office in Atlanta, GA., continues to advise that if the product is to be used in float-beds (within greenhouses or outside), then specific instruction must also be included on the label to either avoid contamination of the float water or guidelines on proper disposal of treated water. In other words, the float-bed is a different site than the traditional ground beds, because of this special requirement of water protection/disposal.

Therefore, the only fungicides labeled for use in all tobacco transplant production systems in Kentucky are Ferbam and Dithane DF, which are covered by special state labels (24-c), because these labels cover all transplant production sites in use. The national labels on Ridomil Gold and Ultra Flourish specifically prohibit treatment of transplant production sites. Streptomycin, an antibiotic, is labeled only for tobacco beds (traditional ground beds), but is not labeled for greenhouse-use nor does the label cover float-beds.

Based on our interpretation of the labels and EPA rulings, the following control options are available for disease control in Kentucky tobacco transplant production as of March 1, 2000.

Greenhouse and Float-Bed Transplant Production Systems:

Follow the agronomic recommendations for general sanitation, media and tray filling, temperature management and ventilation, fertilization, water quality and clipping.

It is most important to prevent and minimize the introduction and build up of pathogens in these wet systems through the following steps: * Sanitize Trays - The two most available methods in Kentucky are washing/bleaching/fumigation and gas- fumigation with methyl bromide. With the bleaching method, trays should be thoroughly washed, dipped in a fresh 10 percent chlorine bleach solution, and immediately enclosed in a fumigation chamber overnight, then aerated several days until the chlorine odors have disappeared. Before using, however, the excess chlorine and chlorine salts will need to be removed by rinsing the trays with clean water and allowing them to air dry to remove chlorine salts. If gas-fumigation is used, the trays should also be washed then gassed with methyl bromide. Stack trays loosely (cross-wise), enclose with plastic and seal, and release from the top of the stack 3 pounds methyl bromide per 1,000 cubic feet of treated space. Warning: This can operation is dangerous and more difficult than for normal plant bed fumigation. The methyl bromide should only be applied out-of-doors and not in a confined space such as a greenhouse. Read, understand, and follow all instructions and precautions on the methyl bromide label! * Regular Protective Fungicide Sprays - Seedlings need to be sprayed weekly with a protectant fungicide to control blue mold, anthracnose, Botrytis, and damping-off. Only two products are labeled in Kentucky for this use - Ferbam and Dithane.

FERBAM at 1.5 - 3.0 lbs/100 gallons of water. Spray preventively twice weekly starting when seedlings have the first true leaf or immediately after plugging with the plug-and- transfer system. Apply as a fine spray to the point of run-off, using 3 gallons of spray material per 1000 sq ft when seedlings are small increasing gradually to 6 to 12 gallons as plants increase in size and the canopy increases. The label has a specific restriction to avoid contamination of the float-water. This use is labeled under a 24-C in Kentucky, which expires June 16, 2000.

DITHANE DF at 0.5 lbs/100 gallons of water (one teaspoon/gallon). Spray preventively on a 5-7 day schedule starting when plants are about the size of a dime and continue until transplanting to the field. This chemical can cause serious injury if applied to smaller seedlings or at high rates. [Note the rate is lower for greenhouse and floats than in the outdoor soil plant beds.] Use 3 gallons of spray material per 1000 sq. ft. while plants are small, but increase gradually to 6 to 12 gallons as plant size and canopy increase. Be sure sufficient water is used to wet the base of the stems with run-off to increase the control potential of damping off. Avoid contamination of the float-water during applications. This use is labeled under a 24-c in Kentucky, which expires June 16, 2000.

Note: Ridomil Gold EC and Ridomil 2E are NOT registered for and should not be used in greenhouses or float beds.

In addition, avoid wetting foliage or allowing high humidity in the greenhouse. Make sure the greenhouse is equipped with a proper ventilation system and that the system is operating to keep leaves as dry as possible. A horizontal air flow system is recommended for this purpose. Add heat at night to drop humidity within the greenhouse. Avoid overtop application of water and fertilizer to keep leaf surfaces dry.

In Kentucky tests, Dithane DF has caused damage to seedlings under certain conditions (especially if the float-water becomes contaminated), but it clearly has provided superior control of blue mold in the outdoor float-beds compared to Ferbam. In greenhouse plantings, significant differences have not been observed in the control of blue mold given by Ferbam and Dithane, but Ferbam was superior to Dithane in Botrytis control at the concentrations labeled.

* For control of Tobacco Mosaic Virus in susceptible varieties avoid using home-grown or manufactured tobacco products in the system. Avoid contact with horsenettle (bullnettle), ground cherry, and tomatoes while working with transplants. Wash hands often (15- 30 minutes) in a 1% phosphate detergent solution, especially before entering and after breaks. Although it is messy, using milk products can be helpful, as whole or skim milk at 5 gals /100 gallons water or dried milk at 5 lbs/100 gallons water per 100 sq. yds. of plants). Spray plants 1 to 24 hrs before handling them. This treatment has also been used successfully prior to clipping of large plants, but it can be very messy unless the system drys well following the application. It should combined with washing the hands at 15 minute intervals either in the clean milk solution or a phosphate detergent.

* Growing other plants in the house with tobacco greatly increases the risk of introducing viruses into tobacco. It is specially important to avoid flowering plants and perennials because of tomato spotted wilt and related viruses transmitted by thrips.

Outdoor Plant Beds:
To reduce disease potential, locate the bed sites in sunny areas and where they have excellent air circulation, avoiding shady areas and old tobacco fields, barns, gardens, and vegetable and insure the bed site has good drainage within and around beds. Follow recommended agronomic practices for fertilization and irrigation, and practice good weed and insect control within and around the bed sites. Fumigation of the bed site, sanitation of the bed site, and regular fungicide/bactericide sprays are important tools in disease control.

Fumigation - To control soil-borne pathogens the site should be fumigated. Fumigant options include: gases, liquids, and granules.

Gases - include products containing methyl bromide or methyl bromide + chloropicrin. Methyl bromide should be used under a plastic tarp at the rates of 9 to 18 lbs/ 1000 sq feet of bed (see labels for specific rates on each product). Methyl bromide + Chloropicrin should be applied at 9 - 13 lbs/1000 sq ft depending on the product used. Bed sites should be prepared as if ready to seed then fumigated for best results. Expose the site to fumigant for at least 24 hrs, plus 24-48 hrs of aeration prior to seeding.

Soil temperatures should be above 55 F during the fumigation period and soil moisture should be sufficient to support germination. Fumigant gases are extremely poisonous, so follow safety precautions.

Liquid fumigants - include products containing SMDC (metham sodium) and marketed under such names as Vapam and Sectagon, but other products may also be available in some areas. They should be used at the rate of 1.5 gallons/1000 sq ft of bed, injected into the soil to a depth of at least 4 inches or more, or drenched into the soil with at least 40 gallons of water/1000 sq ft of bed area, then covered immediately with plastic tarp. The tarp should be left in place at least 24-48 hrs, but a long aeration period of 21 days is needed prior to seeding. Light tillage of the soil during the aeration period may be helpful to speed escape of the fumigant. Be sure that tillage equipment is very clean to avoid re-contamination of the soil.

Granule fumigants - are available as dazomet, sold as Basamid, and used at 7.5 lbs/1000 sq ft of bed. The availability of this product is limited in Kentucky currently, but it is an effective fumigant when used correctly. Since it has a very long aeration requirement (14-50 days), its use in the spring in Kentucky is greatly limited. Granules should be spread evenly over the bed site and incorporated to a depth of 8 inches, then the site sealed completely with plastic. Leave the plastic in place at least 5 - 7 days, then aerate the site until it is safe to seed, as determined by use of a germination test.

COPPER DRENCH - Use Bordeaux mixture (bluestone-lime mixture) as a drench to the soil when the plants have emerged and again 10 days later. This treatment will control algae and aid in the control of diseases caused by bacteria (wild fire, angular leaf spot, and blackleg). Follow the label EXACTLY as to mixing instructions, because Bordeaux mixture can be toxic to tobacco seedlings. Do not apply this mixture to large seedlings. The target is actually the soil and not the tobacco plant.

STREPTOMYCIN SPRAYS - Regular sprays of Streptomycin (sulfate or nitrate) are highly effective in control of most bacterial diseases of the bed, especially angular leaf spot, but streptomycin-resistant strains are present in Kentucky. Sprays can begin as early as the two-leaf stage and should be repeated weekly (not to exceed five application) until transplanting for control of bacterial leaf spots, such as angular leaf spot. It may also slow or suppress blue mold under certain conditions, but cannot be relied on to control blue mold. The material should be applied as a 100 ppm solution (1 teaspoon of Streptomycin 17% WP to a gallon of water), using 3 to 5 gallons of material per 1000 sq ft of bed. On beds receiving Bordeaux mixture, it is not necessary to start the streptomycin sprays at the two-leaf stage, rather they can be delayed until plants are about the size of a dime, unless bacterial leaf spots are observed earlier. Do not mix streptomycin with other spray materials and do not exceed the recommended rate because plant injury could result. Since streptomycin is a local systemic, best results are achieved when it is applied under conditions of slow drying (such as just before dark).

FOLIAR FUNGICIDE SPRAYS - When plants are about the size of a dime, begin weekly sprays with fungicides: Ferbam is available in several formulations with a national labels for outdoor beds, and Dithane DF use is supported by a 24C label that expires June 16, 2000. Ferbam should be used at 1.5-3.0 lbs/100 gallons of water (3 to 5 tablespoons per gallon) and Dithane DF at 0.5-1.0 lbs/100 gallons (1 TO 3 TEASPOONS per gallon). Use 3 gallons of spray mixture per 1000 sq ft of bed while plants are dime-size, increasing to 6 gallons on large plants nearing transplanting size. Thorough coverage of the seedlings is very important. These fungicides are broad-spectrum and will control or suppress a range of fungal diseases associated with the bed, including metalaxyl-insensitive strains of blue mold. Weekly sprays should continue until transplanting time. Should a broad-spectrum fungicide be needed prior to the plants reaching dime size, use Ferbam. Dithane DF can cause serious damage to small seedings, but it has the better efficacy once seedlings are larger and the canopy is dense.

Ridomil Application to Soil ??? - Ridomil Gold EC and Ultra Flourish are NOT labeled for plant-bed use. The old formulation of Ridomil 2E may be used as long as supplies last. At seeding, apply 4 teaspoons of Ridomil 2E per 100 square-yard bed (900 square feet). Apply in sufficient water to spray the entire bed, then rake or rototill the treatment to insure incorporation in the top 2 inches of soil. Note: The supplemental applications in the beds are not supported by the old national label, as these were covered under state labels, which have expired.

SPECIAL NOTICE: Acrobat MZ is NOT labeled for used in any transplant production system. The Special Exemption expired on September 30, 1998 and the manufacturer has elected not to support labeling this product for use in transplant production systems because of concerns about dimethomorph-resistance. Use of carry-over Acrobat MZ is NOT authorized for transplant production systems (Emergency Exemptions cover a period of time, not the life of the product).

For current blue mold information, go to the Ky Blue Mold Warning System at:
http:// www.uky.edu/Agriculture/kpn/kyblue/kyblue.htm

WINTER GRAIN MITE
By Doug Johnson

You may recall winter grain mites were reported in wheat back in January (KPN #869 January 10, 2000). I have just viewed some wheat which was suspected of having aphids but the wee beasties turned out to be winter grain mites. This is really good on two counts. First, winter grain mites cannot spread BYDV and second, all of them were dead.

Very little is known about this mite. We usually do not have a problem in Kentucky probably because the preferred method of control is rotation with a non-grass host. Our typical rotation of corn - wheat - soybeans - fallow probably does as good a job of prevention as is possible.

This mite has two generations per year. The first generally starts in September or October and peaks in December or January. The second begins from eggs laid by the first and peaks in March or April. The second generation lays eggs that over-summer. These eggs will not hatch until the fall.

Temperature and moisture are very important to this mite's survival. The mites are most active at temperatures between 40o and 70oF. They will generally be found near the base of the plant and under ground. On cool overcast days the mites will feed higher on plants but under hot and /or dry conditions they descend to the base of the plants and / or move under ground seeking moisture and temperature moderation.

Since our spring temperatures rapidly reach 70 F and above, and our rotation practices include no grass plants, this mite is not likely to cause us a problem. At this point, the most important effect of seeing winter grain mites is not to mistake them for aphids. Mistaken identity could cause a producer to make an unnecessary insecticide application.

IDENTIFICATION AND CONTROL OF WEEDY GRASSES IN WHEAT
By James R. Martin

During the last few weeks a number of samples of weedy grasses including Italian ryegrass (also, known as annual bluegrass), little barley and annual bluegrass were collected and sent in for identification. Other weedy grasses that can occur in wheat this time of year include cheat, hairy chess, downy brome, field brome. All of these species normally emerge in the fall and mature the following spring or early summer. The dry conditions in 1999 has in many cases delayed emergence of weedy grasses; consequently, growers may have overlooked these problems when scouting wheat fields last fall.

Correct identification will be important in planning a management strategy. Unlike most weedy grasses, Italian ryegrass has auricles or claw-like structures that clasp around the stem near the base of the leaf blade. Its leaves and stems do not have hairs and tend to be glossy. Hairy chess, downy brome, and field brome have hairs on leaf sheaths, while, cheat lacks hairs. Little barley can often be identified by digging plants and checking around the roots for seed with numerous awns. Annual bluegrass grows in tufts (clumps) and has boat-shaped leaf tips. Some of these key characteristics are illustrated in Figure 1.

Italian ryegrass occurs more frequently in Kentucky compared with the other species in this group. This may be good news since Italian ryegrass tends to be controlled more easily than the other weedy grass species that occur in wheat. Achieve is a relative new postemergence wheat herbicide registered for controlling ryegrass. Limited research indicates that Achieve provides control similar that obtained with Hoelon.

As a general rule, treatments should be made before plants overwinter and tiller. The fact that ryegrass emergence has been somewhat delayed this season will be beneficial where problem fields have not yet been monitored and treated. However, because of the recent warm temperatures that occurred in Kentucky, ryegrass plants may have grown well beyond the size recommended for optimum control. The maximum growth stage of ryegrass is 5 leaves to 2 tillers for Hoelon and 4 leaves (total leaves including tillers) for Achieve.

In order to minimize the risk of crop injury, check the weather forecast to help plan when to spray. Avoid spraying when cold temperatures (usually less than 35 to 400 F) are predicted a few days before and after application.

Sencor is registered for suppression of such weedy grasses as cheat, downy brome, little barley, and annual bluegrass. Treatments must be used only where wheat varieties are tolerant to Sencor. These is probably no benefit in spraying Sencor if weedy grasses have more than 2 leaves.

Consult the product label for specific information on herbicide rates and timing of application as well as precautions

Figure 1. Identifying characteristics of seedling weedy grasses that occur in wheat.

SOUTHWESTERN CORN BORER SPRING SURVEY
By Ric Bessin, Wayne Mattingly, & Mike Smith

A survey of Southwestern corn borer damage and larval survival was conducted in Daviess and Henderson between February 29 and March 2. These counties were selected because of their history of damage. The purpose was to estimate the extent of SWCB damage, as evidenced by basal stalk girdling. In addition, we wanted to estimate the survival of the larval in the crowns of these damaged plants. In each county, five or six fields were evaluated. Within each field, 10 groups of 10 plants were examined for girdling damage and presence of live SWCB larvae. An additional 50 damaged plants were examined for the presence of live SWCB larvae.

2000 SWCB Spring Survey Results

Daviess County
	Damaged plants	Live SWCB recovered
Farm #1	26/100	19/50
Farm #2	15/100	13/50
Farm #3	34/100	19/50
Farm #4	27/100	10/50
Farm #5	36/100	12/50

Henderson County
	Damaged plants	Live SWCB recovered
Farm #1*	1/100	7/9
Farm #2	29/100	21/50
Farm #3	7/100	12/50
Farm #4	37/100	11/50
Farm #5**	7/100	5/50
Farm #6**	9/100	5/40

*Bt-corn
** Fall tilled corn

This is the second year that we have conducted such a survey, so it is important to understand that we need to take care to not jump to inappropriate conclusions over the results. At this time, we cannot conclude that this will be a light, moderate or severe year for the SWCB in any of the counties surveyed. We cannot say whether or not this year will be better or worse than last year, although there were greater numbers of live southwestern corn borer larvae in girdled stalks. However, because corn was planted "on-time" last year, the level of stalk girdling was reduced.

Overwintering survival is just one of the variables that will, in part, determine the potential for SWCB problems in 2000. Historically, the date of planting of individual fields has been a key variable contributing to the potential for late season SWCB damage. Typically, fields planted after May 5 have an increased potential for this type of damage.

What we can conclude:

• We found live SWCB larvae in each of the counties surveyed.
• Winter temperatures were not sufficient to eliminate SWCB larvae
• SWCB remains a threat in some areas for 2000
• Date of planting will determine the potential for SWCB injury in these counties.

GUIDELINES FOR PLANTING CORN HYBRIDS WITH GRAY LEAF SPOT RESISTANCE
By Paul Vincelli

Within the last several years, seed companies have made available a wide selection of corn hybrids with partial resistance to gray leaf spot. I stress the word partial resistance, since none that are currently on the market have immunity to gray leaf spot. This term also conveys the fact that hybrids with partial resistance differ in how much resistance they have. Some hybrids only have a low level of resistance; others have a moderate level; still others may have a high level. In spite of the fact that no hybrid is immune, moderate to high levels of partial resistance can be very useful.

The inoculum (infectious spores) for gray leaf spot outbreaks survives in residue of corn leaf blades and sheaths left on the soil surface. Corn is the only known significant host plant of this disease, and the blades and sheaths of leaves are the only plant parts affected. The spores of the fungus are spread by air, so only corn residue left on the soil surface can produce inoculum that can spread to the next corn crop. Given these facts, it is not surprising that gray leaf spot tends to be more of a risk under conservation tillage systems.

Producers should consider planting corn hybrids with moderate to high levels of gray leaf spot resistance when planting corn into fields where:

last year's crop was corn, regardless of the tillage system, OR the field was in corn two years ago and is being maintained under minimum tillage (30% or more residue cover), OR there is untilled corn residue from last year in a nearby field within 300-500 feet.

These guidelines are meant to be relatively conservative in terms of minimizing yield loss from the disease. These guidelines are a change from the recommendation issued in previous years, which was to use hybrids with partial resistance when planting into, or within 300-500 feet of, heavy amounts of corn residue from the previous season. This change is based on the relatively wide choice now available among hybrids with partial resistance to gray leaf spot and the fact that a one-year rotation without tillage is sometimes not sufficient to reduce inoculum levels to nondestructive levels in a field with a substantial amount of corn residue.

The amount of infested corn residue left on the soil surface is one of the principal factors that govern gray leaf spot pressure but it is not the only factor. Weather during the growing season which is unpredictable is another factor. Date of planting can also be important, as earlier crops are less at risk than late-planted crops. Finally, site related factors such as degree of air movement and amount of fog can be important. Producers should also consider these factors when selecting hybrids.

EARLY WEEVIL DEGREE DAY ACCUMULATIONS
By Lee Townsend

Degree day accumulations (base 48o F) are important in anticipating alfalfa weevil development. The accumulation of 190 degree days (beginning Jan 1) is the time when we can look for the first signs of feeding activity in alfalfa tips. By this point, some of the fall-laid eggs are beginning to hatch. We have reached this level in much of the southern portion of the Commonwealth.
Selected degree day accumulations as of March 5 -

• Bardstown 186
• Bowling Green 199
• Covington 104
• Glasgow 235
• Lexington 138
• Princeton 260
• Somerset 185.

Keeping track of degree days over the next few weeks will be important in preventing surprises from alfalfa weevils. It is a mistake to treat too early- especially at the first sign of feeding in a field. Most of our potential feeding damage comes from spring- laid eggs that will hatch considerably later than those laid in the fall. Follow the degree day charts and use the 30 stem sampling technique for accurate decision-making information.

The first chewing damage seen on alfalfa tips is often caused by clover leaf weevils. They spend the winter as partially grown larvae and are active very early in the season. These small, legless grubs have a distinct white stripe, lined with red, running down the middle of their back. Often, they are responsible for the first tip feeding of the spring.

OBTAINING WEATHER DATA FOR APPLE IPM
By John Hartman

Growers of specialty crops in Kentucky recognize that diseases have an effect on the quality of their produce and that the weather has a great influence on diseases of these crops. For many crops, accurate weather information is essential for plant disease management, especially if growers are using IPM approaches.

A significant feature of the Kentucky apple IPM program has been the acquisition and use of weather and microclimate information for orchard disease and insect management. Over the years we have demonstrated the importance and uses of instruments ranging from maximum-minimum thermometers and rain gauges to microcomputer-based orchard weather monitors. It is important for growers to know the weather because many disease and insect life cycles are tied to temperature (degree days), humidity, rainfall, and leaf wetness. In addition, weather affects orchard management practices such as spraying. Apple growers have learned the importance of weather in management of scab, fire blight, sooty blotch and flyspeck as well as several insect pests.

An on-site weather station is excellent for learning about the weather that has occurred in the orchard, but growers also need weather forecasts. There are now available good and cost-effective options for monitoring orchard weather. For forecasts, however, growers also need access to other weather information sources. What follows is a review of weather monitoring options for fruit growers. Although the emphasis of this article is on apples, these resources are also valuable to growers of other high-value crops such as small fruits, vegetables, and ornamentals.

Traditional weather forecasts and current conditions available to the public. Most of us are used to learning about the weather through the newspaper, radio, recorded messages, and television. Unfortunately, these reports are quite variable and may not necessarily apply to your specific orchard. Nevertheless, most of us rely on reports that are familiar and reasonably reliable over the years. If cable or a satellite dish are available, The Weather Channel is the most frequently updated, and arguably the most accurate source of current conditions and forecasts.

Weather radio. The National Weather Service (NWS) broadcasts frequently updated weather information that can only be received via the special Weather Radio broadcast band. These originate from National Weather Service offices in Kentucky and nearby states and throughout the United States. Weather Radio is broadcast at a frequency of 162.400 or 162.550 Mhz. Growers need to invest in a special weather radio to receive it. Weather Radio has the added benefit of audible warnings/alerts when severe weather is imminent.

The internet. The internet has become a good resource for up-to-date weather information. Numerous world wide web sites feature weather information and some are listed here. Although these sites may be able to provide hourly temperature, relative humidity, and rainfall data, none provide leaf wetness information.

--The University of Kentucky Agricultural Weather page (www.agwx.ca.uky.edu). The U.K. Agricultural Weather page can be set to provide specific information by county. This site has won awards for excellence.
--The Weather Channel (www.weather.com).
--Accuweather (www.accuweather.com).
--National Weather Service (www.nws.noaa.gov).

A note about internet sites: In the next sections, some internet sites are listed as a way for fruit growers to get more information about weather monitoring equipment or services. Just because you don't have a computer, or subscribe to an internet site, doesn't mean that you will be unable to look up this information. All County Cooperative Extension Offices in Kentucky have access to the internet. If you really need to get information about weather monitoring equipment or services to assist you in your fruit growing operation, our County Extension Agents will be more than happy to help you look up these internet resources.

Commercial services providing weather information.
--A commercial weather service we have tried in Kentucky is SkyBit, P.O. Box 10, Boalsburg, PA 16827-0010, (tel. 800/454-2266), (www.skybit.com). SkyBit offers detailed (hourly) and site-specific (down to one meter square, based on latitude/longitude and elevation) weather observations and forecasts including leaf wetness. SkyBit also takes basic weather data and customizes it so it is more useful to clients such as fruit growers, including spraying tips and apple disease and insect predictions. SkyBit has a monthly subscription fee, and they also offer a free trial period. Their products can be delivered via fax or e-mail.

--Another commercial weather service growers may be familiar with is the Data Transmission Network (DTN), (www.dtn.com). They offer frequently updated satellite weather images and forecasts, as well as commodity information, for a monthly or annual fee.

--Accuweather (www.accuweather.com) also can, for a subscription fee, customize weather observations and forecasts for a location specified by zip code. A thirty-day free trial subscription is available.

On-site weather stations. In the past, many growers have been reluctant to purchase orchard-based weather stations because they were expensive and difficult to calibrate and maintain. Now, however, there are some less expensive and accurate weather monitoring stations available. Often they are paired with a personal computer application that helps to visualize the collected weather data and use it for pest and disease models that aid in decision-making.

Although an inexpensive maximum-minimum thermometer and a rain gauge will work well for fire blight management programs such as MARYBLYT, most other disease predictive programs rely on leaf wetness measurements. In looking for weather monitors, growers will need instruments that measure temperature, leaf wetness, relative humidity, and rainfall. Growers will also need to have access to computer programs that can make predictions based on these weather data. Many of the companies selling weather monitoring equipment also have computer- based disease predictive and management programs available.

The following are some examples of orchard-based weather monitoring instruments and predictive programs that fruit growers might find useful. Addresses, telephone numbers, and internet addresses are included. This is not necessarily a complete list and there is no attempt to discriminate between weather monitoring systems, but it does provide an idea of what is available.

• Spectrum Technologies, 23839 W. Andrew Rd., Plainfield, IL 60544 (tel. 800/248-8873), (www.specmeters.com) sells a small weather station that records temperature, relative humidity, leaf wetness, and rainfall. Coupled with a laptop computer and the appropriate software, weather data can be graphed, and scab or fire blight infection or other models can be run. Weather information is stored in a small electronic box called a data logger. The data logger is periodically detached and connected to a computer in the office, or a portable computer is connected to the data logger in the orchard. However, one could run a cable (a few hundred feet) from the data logger to the computer. We used this unit in our disease management experiments last summer and it appeared to work well.
  
• In our 1999 apple IPM program, we demonstrated the Show-Me Plant Disease Forecasting System. This unit measures temperature, leaf wetness, humidity and rainfall in the orchard and sends the information by radio to a computer located in the office. This unit can be equipped with many different disease forecasting systems ranging from fruit diseases to tomato or turfgrass diseases. Information on the Show-Me is available at: Electronic Instrument Lab, 17 Physics Bldg., University of Missouri, Columbia, MO 65211, (tel. 314/882-4024). It can alternatively be directly wired to the computer, up to 1000 ft. As in all directly wired instrument applications, lightning protection must be considered.
  
• Davis Instruments (www.davisnet.com) is another producer of moderately priced agricultural weather stations that are reliable, and simple to set-up and use. Their weather equipment also interfaces with a computer application that allows easy manipulation and graphical viewing of collected weather data. The Davis weather monitors are available from Gemplers, P.O. Box 270, Belleville, WI 53508, (tel. 800/382-8473), (www.gemplers.com).
  
• In the past, we have demonstrated the METOS disease predictor at our U.K. experimental orchard in Princeton. This stand-alone unit has the microcomputer built into the weather monitor. A small printer provides the grower with needed information each time the unit is visited in the orchard. It is available from: METOS Instruments, Dale Hardin, 5100-318 S Cleveland Ave, #385, Fort Meyers FL 33907, (tel. 941/277-1984, fax 941/277- 1986), e-mail: (aiti@gate.net).
  
• The Sensor Instruments, Co., Inc., 41 Terrill Park Drive, Concord, NH 03301, (tel. 800/633-1033) sells a field monitor weather data logger that detects and records weather information for orchard and field applications.

These are but a few examples. Although we cannot change the weather, we can certainly become better informed about how the weather affects disease and insect problems in the orchard. Without good weather data, an IPM approach to managing diseases and insects in the orchard becomes difficult. Growers need to be able to know the best time to apply control measures; hence, weather monitoring is essential to the practice of efficient IPM.

SEVERAL FUNGICIDES NO LONGER AVAILABLE FOR HOME LAWN USE
By Paul Vincelli

Three fungicidal active ingredients used to control turfgrass diseases are no longer labeled for use on residential lawns. These fungicides are chlorothalonil, iprodione, and vinclozolin; see the accompanying table for trade names of formulated products.

The restriction of these products from use on residential lawns is a recent development, and is intended to reduce overall human exposure to these fungicides consistent with the Food Quality Protection Act. As specified on their current labels, these products are still registered for a variety of turf uses, including golf courses, sod farms, athletic fields, and commercial/industrial turf uses.

This restriction will probably be most important from the standpoint of controlling brown patch, the most common disease of tall fescue in Kentucky. With many lawns being renovated this spring in order to recover from last year's drought, brown patch could become a significant factor reducing the successful establishment of these young grass plants later in summer. Alternative products may need to be on hand for these situations. Commercial applicators have access to azoxystrobin (Heritage) and flutolanil (Prostar), excellent systemic fungicides for control of brown patch. A new "mesostemic" fungicide called trifloxystrobin (Compass) also has excellent activity against brown patch. To my knowledge, none of these fungicides is available in formulations for use by the homeowner. More will be written about brown patch control later in the year.

Any existing stocks of these products without the residential-lawn restriction may be used on home lawns, until such stocks are exhausted.

REVISED RISK ASSESSMENTS FOR ACEPHATE AND METHAMIDOPHOS RELEASED; RISK MANAGEMENT COMMENTS REQUESTED
By Lee Townsend

On February 22, the EPA released the revised risk assessments for the organophosphate (OP) insecticides acephate (Acephate, Orthene) and methamidophos (Monitor). The assessments for these two OPs is being done together because acephate degrades to methamidophos. Major parts of the assessments include use profiles, human health risk including acute (short-term) and chronic (long-term) dietary (food) risk, drinking water dietary risk, occupational and residential risk, and ecological risk including nontarget animals. There are several concerns about these risks, especially relating to children and nontarget animals. If one or both of these pesticides are important to you, you can access the detailed assessments at the following web sites:
acephate: http://www.epa.gov/pesticides/op/acephate.htm
methamidophos: http://www.epa.gov/pesticides/op/methamidophos.htm.

There is an opportunity for a 60-day public comment period during which you may submit risk management and mitigation ideas, and recommendations and proposals for transition related to acephate and methamidophos. Comments must be received by April 24, 2000 identified by docket number OPP-34164B for acephate and OPP-34166B for methamidophos. For more information contact Karen Angulo at 703-308-8004 or by email at angulo.karen@epa.gov.

DIAGNOSTIC TIPS FOR DROUGHT- RELATED PROBLEMS
By Julie Beale

With spring just around the corner, we are beginning to see more samples in the Diagnostic Laboratory lately. In the past week we have seen several samples from greenhouses all showing nutritional or environmental problems, but no infectious diseases. We have seen samples of tomato seedlings with symptoms of exposure to ethylene (from poorly ventilated heating systems); New Guinea impatiens with symptoms of ethylene exposure and excessively high soluble salts; geraniums with growth regulator damage; and pansies with poor growth due to high pH in the growing media. From landscape situations, we have seen many conifers showing damage from last year's drought, as well as a few blue spruces with Cytospora canker a fungal canker disease often associated with drought-stressed trees. We have had a case of yellow patch (Rhizoctonia) on commercial turfgrass and several mushrooms to identify from home lawns.

PESTICIDE APPLICATOR TRAINING SCHEDULE

Details are posted on the Pesticide Applicator Training Web Site

  http://www.uky.edu/Agriculture/PAT/welcome.htm

SOUTHERN PINE BEETLE

By Jeffrey W. Stringer, UK Dept. of Forestry

The southern pine beetle has been active recently in areas of southeastern Kentucky. It can attack shortleaf pine, Virginia pine, pitch pine, loblloly pine, and occasionally eastern white pine. Southern pine beetle adults can easily detect weakened trees. They bore into them and emit chemicals which attract other adults. Females lay eggs and the larvae feed on the inner bark killing the tree. Once the tree shows signs of attack, it is usually at a point where it cannot be saved. These trees should be removed and destroyed.

Spread of the beetles usually occurs from a single attacked tree or group of trees. If dead or dying trees are found to be infected with southern pine beetle these trees should be removed, as well as others surrounding them. Many pine trees have been stressed due to the drought of last year and are extremely susceptible to attack.

The insect is indigenous and population levels are cyclical. Populations tend to reach epidemic proportions in Kentucky at approximately 20 to 25 year intervals. The Daniel Boone National Forest is currently working on sanitation projects on their property in southeastern Kentucky. You can get more information on damage, how to detect attacks of southern pine beetles, and control at:
http://everest.ento.vt.edu/~salom/Hndbk558/558.html

Lee Townsend
Extension Entomologist

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