Illinois Fruit and Vegetable News:

A Newsletter for Commercial Growers of Fruit and Vegetable Crops
A Publication of University of Illinois Extension and the College of Agricultural, Consumer, and Environmental Sciences

Vol. 9, No. 3, April 4, 2003

"We are what we repeatedly do. Excellence, then, is not an act, but a habit." --Aristotle

Address any questions or comments regarding this newsletter to the individual authors listed after each article or to its editor, Rick Weinzierl, 217-333-6651, weinzier@uiuc.edu. To receive email notification of new postings of this newsletter, call or write the same number or address.

This issue's words of wisdom ... which usually means the jokes ... are at the end of newsletter ... check the last page.

In This Issue:

Crop Reports (Notes from Dixon Springs, southern Illinois, and northern Illinois)

Degree Day Accumulations

Notes from Chris Doll (Crop phenology, boron, the Illinois Fruit Calendar, congratulations to Ken Hall and Richard Tanner)

New Registrations (Notes on several herbicide and fungicide registrations)

Fruit Production and Pest Management (Woolly apple aphid, San Jose scale, petal-fall insecticides for apples, flea beetles and cutworms in grapes, eastern flower thrips in plasticulture strawberries)

Vegetable Production and Pest Management (Asparagus beetles in asparagus, flea beetles in sweet corn)

University of Illinois Extension Specialists in Fruit & Vegetable Production & Pest Management

Crop Reports

In the south and southwest, crops fared well through the low temperatures experienced in the early morning of March 30. The Edwardsville area experienced lows ranging from 32-34°F. Reports are promising for all tree fruit and small fruit crops. Further south, apricots are close to shuck split, peaches are at petal fall, and early variety apples are showing pink. Bloom thinning of peaches has been reported at several locations. Asian pears are in tight cluster, and sour cherries are in full bloom. Plasticulture strawberries are growing well, with the early variety 'Sweet Charlie' in full bloom. Plasticulture strawberries in the northern portion of the region are exhibiting a small amount of frost injury to the blossoms. For matted row strawberries, mulches are just being pulled off in the northern most areas of the region. Brambles have pushed out several inches of new growth, and blueberries have noticeable flower buds. Walnut and pecan trees have not shown any significant developmental changes. Asparagus is ahead of schedule, and being harvested in many locations.

Elizabeth Wahle (618-692-9434; wahle@uiuc.edu)

From the Dixon Springs Agricultural Center ... I thought the month of March was supposed to be windy, but so far April has nearly blown us away. We have been experiencing 25 mile per hour winds for about 5 days in a row ... would make for severely displaced herbicide applications, but at least the ground is drying out. Our apple varieties are ranging from green tip to tight cluster with pink just a couple of days out, so we are gearing up to make strep sprays at first bloom. We are currently potting tomato and pepper plants for summer variety trials as well as spreading sawdust for mulch in the blueberries. The plasticulture strawberries are really growing and received their third fertilizer application earlier in the week. Without Sweet Charlie in the planting, we didn't anticipate any early blooms, but the JP 4 variety has started to flower (though it lacks in plant size).

Bronwyn Aly (618-694-2444; baly@uiuc.edu)

In northern Illinois, low temperatures in the upper 20s to low 40s and highs in low 40s to low 60s have characterized most of the last several days, but early this week (beginning of April), day temperatures were in the high 70s. Scattered showers are in the forecast, so maybe we'll see improved moisture status. Only trace amounts of rainfall have been recorded this month (from beginning of April) and about 2 inches since the beginning of the year in northern Illinois.

Pruning and training of non-bearing trees is still going on in some orchards, and apples remain dormant. Dormant oil sprays are going on in most orchards, and fire blight control spray programs are beginning in some orchards. Fertilizer and herbicide application in the orchards are almost complete. Grape buds are still dormant. Growers with greenhouses have started vegetable seedlings indoors, which should be ready for transplanting outdoors in May.

Maurice Ogutu (708-352-0109; ogutum@mail.aces.uiuc.edu)

Projections for degree day accumulations two weeks into the future are derived by adding historic averages for degree days for the next two weeks to the actual current total listed for each location (March 31 in this instance).

Kelly Cook (217-333-6651; kcook8@uiuc.edu;) Rick Weinzierl (217-333-6651; weinzier@uiuc.edu)

Notes from Chris Doll

Phenology Update
As of April 3, Red Delicious apples are ready to separate from tight cluster and most peaches are approaching full bloom. The manual degree day determination is 253 DD at base 45 degrees, and 173 DD at base 50 degrees. These numbers match up pretty well with the phenology/DD material shown on page 29 of the Michigan Fruit Management Guide and also on pages 64 and 65 of the New York Commercial Tree Fruit Production book for 2003.

Apricot bloom is past and appears to have survived the light freeze last Sunday. Japanese plums are in full bloom and most of the domesticas are pushing into the white bud stage. Some sweet cherries are in full bloom and the tarts are in full bud swell. Strawberries have turned yellow under any remaining straw mulch, and Sweet Charlie's are blooming out in the plasticulture fields. So, spring is here as indicated by the fruit crops, and we are eight days ahead of 2002 and six days ahead of 2001. It is hoped that the freeze figures in the Spray Guide will not materialize. The book says that 90 percent kill is possible on apples at 21 degrees and at 24 degrees on peaches.

Crop notes
Peach bloom looks good for the area and thinning appears to be a concern. Blossom thinning is a feasible method if freezing temps do not follow to reduce the remaining flowers or fruits. It is most successful on some of the heavy blooming early varieties such as Red Haven. The bloom is a little lighter in blocks that suffered from drought stress last summer while trees were carrying a good crop, but all have enough for 2003 at this time. Some delay in bloom has been seen from Ethrel sprays, but unless a few check trees were left, growers wont see this.

Apples should have a full, full-bloom in most blocks this year. The bud set on dwarfing stock such as Bud 9 and M9 is truly amazing in comparison with M7 and MM111, but there should be enough bloom on everything. Thoughts of thinning apples will be forthcoming soon.

Boron is a critical element in the pollination process and is suggested in most apple spray schedules for use in pink, bloom, and petal fall applications. Again, remember to have all soluble bagged pesticides dissolved before adding the boron. And, you might take a pH reading of spray tank water after adding the boron to see if a reducing agent is needed.

The Illinois Fruit Calendar, C1122 of the University of Illinois, was last published in 1987 as far as I know. I have preserved my issue and use it regularly to see what is forthcoming based on crop development. For instance, as pink on apple approaches, European red mites are beginning to hatch, red-banded leafroller should be laying eggs as are leaf miners, and curculio are coming out. Tarnished plant bugs could be present in peach orchards. Tree training should be ongoing, and limb spreaders should be in place. Bees for pollination should be arranged for. Red raspberry growers that need Ridomil for Phytopthora control should makes applications now.

Miscellaneous
Dr. Richard Funt and Dr. Mark Schmittgen of Ohio State University have published an "Ohio Fresh Market Peach Business Plan for 2003" and have included the most up-to-date cost of establishment and production data that I have seen. A quick digest of spray figures indicates that it requires $394 worth of chemicals for 8 sprays, and application costs of $227 for equipment and labor. A 12-year peach orchard with one freeze-out had a net profit of 4% when fruit was sold at $.50 a pound, and this increased to 19% when the fruit was sold at $.70 a pound.

A Southeast Peach newsletter reported a cost of $12.90 per acre for labor and equipment use. Figures like that will vary, especially if a grower is using a 30 year-old sprayer and tractor.

Congratulations are in order for two of our very good fruit growers and marketers. Ken Hall of Edward Orchards at Poplar Grove is the current president of the International Dwarf Fruit Tree Association. Richard Tanner of Tanner's Orchard at Speer is the current president of the North American Farm Direct Marketing Association.

Chris Doll

New Registrations

News on Herbicide Registrations
Sandea is Registered on Many Vegetable Crops: Sandea (active ingredient halosulfuron) has been registered by the Gowan Company for use on asparagus, cucumbers (including pickles), pumpkins, winter squash, summer squash, muskmelon, watermelon, snap beans, lima beans, tomatoes, peppers, and eggplant. Sandea is effective both preemergence and postemergence, although the type of application allowed varies with the crop. The herbicide is absorbed through roots and shoots and is translocated throughout the plant.

Sandea controls a number of problem weeds but must be combined with another herbicide for grass control. Probably Sandea's biggest plus is when applied postemergence, it will control yellow nutsedge. Preemergence applications of Sandea control galinsoga, kochia, common cocklebur, jimsonweed, ladysthumb and Pennsylvania smartweed, common lambsquarter, redroot and smooth pigweed, and velvetleaf. Postemergence applications of Sandea will also control pokeweed and giant ragweed but will not control jimsonweed and common lambsquarter. Irrigation or rainfall (1/4 to ½ inch) will improve preemergence activity by incorporating and activating the herbicide. Postemergence applications should be made to actively growing weeds 1 to 3 inches in height.

The registrations for Sandea vary somewhat depending on the region of the U.S. The use rate is generally ½ to 1 ounce of Sandea per acre. I will just highlight a few of the new registrations for Sandea. In Illinois, Sandea is registered on asparagus, both transplants, 6 weeks after fern development and established beds. This is one of the few herbicides registered for newly transplanted asparagus. It will provide broadleaf weed control and Poast or Fusilade can be used to control emerged grasses. Contact with the fern may cause temporary yellowing. Weed control will be more effective when Sandea is applied with drop nozzles to direct the spray below the fern and to get more complete weed coverage.

Sandea is now registered for use on a wide range of cucurbit crops, including direct seeded or transplanted cucumbers (including pickles) and cantaloupes, direct seeded pumpkins and winter squash and in row middles for muskmelon and watermelon. Postemergence applications of Sandea can be made at the 2 to 5 true leaf stage of direct seeded plants and at 14 days after transplanting. The ability to use Sandea postemergence on cucumbers, cantaloupes, pumpkins, and squash provides postemergence broadleaf control that was impossible in the past.

Another important use that Sandea allows in cucumbers and tomatoes are applications under plastic mulch. This application is especially important to suppress yellow nutsedge. Sandea should be applied to the soil surface after final bed shaping and before installation of the plastic mulch. This will increase the passes through a field for people with bed shapers that also lay plastic. Also transplanting must be delayed until 7 days after installation of the plastic.

The active ingredient in Sandea, halosulfuron, is an acteolactate synthetase inhibitor (ALS inhibitor) which is the same mechanism of action that Classic, Scepter, Pursuit, Accent, Beacon, etc have. The problem with this category of herbicides is that weeds (especially pigweeds and water hemp) can rapidly develop resistance to ALS inhibitors. Reduce the potential for weed resistance to Sandea by combining it with other herbicides and weed control strategies such as cultivation. Also when rotating crops avoid using Sandea multiple years in a row and scout fields for newly occurring resistant weed biotypes.

The Sandea label also contains several precautionary statements to reduce the potential for crop injury and to ensure adequate weed control. Even with these limitations, Sandea will be a welcome addition to the herbicides registered for vegetable crops.

DuPont Expands the Sinbar Label for Strawberries: Sinbar is a herbicide that has been registered for use on established strawberries either at renovation or just prior to mulching in the fall. Recently, DuPont, the manufacture of Sinbar has expanded its label to allow the use of Sinbar during the planting year. Sinbar can be applied at 2 to 3 ounces/acre after transplanting but before new runner plants start to root. A second Sinbar application at 2 to 6 ounces/acre can be made in late summer or early fall to control winter annual weeds. A third application at 2 to 4 ounces/acre can be made just prior to mulching in the fall. This third application will extend weed control through harvest in the following year. Use rates for Sinbar vary depending on soil type and amount of organic matter.

Sinbar can be absorbed through the foliage and cause injury, if the plants are actively growing and forming new leaves. To prevent injury, Sinbar applications to actively growing strawberry plants must be followed immediately by 0.5 to 1 inch of irrigation or rainfall to wash the Sinbar off the strawberry foliage. Strawberry varieties can vary in their tolerance to Sinbar and less vigorous plants tend to be injured. Before using Sinbar for the first time on a new planting conduct a trial on a small section of the planting to determine the potential for injury under your field conditions.

Aim Herbicide on Sweet Corn: Aim (active ingredient carfentrazone-ethyl) herbicide manufactured by FMC can be used for postemergence weed control in either fresh market or processing sweet corn. Unlike other newly registered herbicides, sweet corn cultivars do not vary in their tolerance to Aim. Aim should be applied to actively growing weeds up to 4 inches high and rosettes less than 3 inches across. Aim at 0.5 fluid ounces (0.008 lb active ingredient)/ acre will control common lambsquarters, ivyleaf and pitted morningglory, eastern black nightshade, redroot pigweed, velvetleaf, common waterhemp, and tall waterhemp. Thorough coverage of the weeds is essential for control. Thus, a nonionic surfactant at 0.25% v/v with at least 80% active ingredient should be included in the spray solution.

John Masiunas (masiunas@uiuc.edu)

New Fungicides for Vegetable and Fruit Crops

Procure 50WS: Procure 50 WS is available for control of diseases of vegetable and fruit crops. Procure 50WS (50% triflumizole), manufactured by Uniroyal Chemical Company, is a systemic fungicide, with broad-spectrum activity on foliar diseases. It has protectant and eradicant activity against powdery mildew of cucurbits (cucumbers, Gherkins, gourds, muskmelons, cantaloupes, honeydews, Persian melons, pumpkins, squash, watermelon); powdery mildew, scab, and cedar-apple rust of apples; powdery mildew and scab of pears; powdery mildew of strawberries; and powdery mildew, blossom blight and fruit rot (Monillinia species) and leaf spot (Blumeriella jaapii) of cherries. It has also been registered for control of grape diseases. For more information on Procure 50WS visit the following website:

http://www.cdms.net/manuf/1prod.asp?pd=786&lc=0

Cabrio EG: Cabrio EG (pyraclostrobin), manufactured by BASF, is a strobilurin fungicide with broad-spectrum activity. Cabrio has protectant and systemic activity against many diseases of cucurbit vegetables (cantaloupe, cucumber, melon, squash, pumpkin, watermelon), fruiting vegetables (eggplant, tomato, bell pepper, chili pepper), root vegetables (carrot, radish), bulb vegetables (onion, garlic, leek), berries (blueberry, caneberry, raspberry), strawberries, cherries (sweet and tart), and pistachio. More information on Cabrio is available in the following website:

http://www.cdms.net/manuf/1prod.asp?pd=6224&lc=0

Headline: Headline (pyraclostrobin), manufactured by BASF, is a strobilurin fungicide with broad-spectrum activity. Headline has protectant and systemic activity against diseases of dry beans, tuber and corm vegetables, (potato, sweet potato, yams), citrus fruit (grapefruit, lemon, lime, tangerine, tangelo), barley, peanut, sugar beet, wheat, rye, and grass grown for seed. More information on Headline is available in the following website:

http://www.cdms.net/manuf/1prod.asp?pd=6223&lc=0

Gavel: Gavel (8.3% zaxomide + 66.7% mancozeb), manufactured by Dow AgroSciences, is a protectant compound, effective against foliar diseases of cucurbits (cucumber, melons, summer squash, and watermelon), potatoes, and tomatoes. Gavel can be used to control cucurbit diseases (Alternaria leaf spot, Cercospora leaf spot, downy mildew, and fruit and stem rot), potato diseases (early blight and late blight), and tomato diseases (Buckeye rot, early blight, Gray leaf spot, late blight, Septoria leaf spot, bacterial speck, and bacterial spot). Gavel may be applied by ground or air at a maximum rate of 2.0 pounds product (1.5 lb active ingredient) per acre. Number of applications and preharvest interval vary with crop. More information on Headline is available in the following website:

http://www.cdms.net/manuf/1prod.asp?pd=5010&lc=0

Acrobat 50WP: Acrobat 50WP (dimethomorph 50%) has been registered for control of vegetable diseases. Acrobat 50WP, manufactured by Corporation, is a protectant fungicide. This fungicide can be used to control downy mildew of bulb vegetables (garlic, leek, onion, shallot); downy mildew and Phytophthora blight of cucurbits (cucumber, melon, pumpkin, squash, watermelon); downy mildew of hops; downy mildew of lettuce and endive; an late blight of potato and tomato. Acrobat 50WP may be applied by ground or air at a maximum rate of 6.4 ounces pound product (3.2 oz dimethomorph) per acre, a maximum of 5 times per season. More information on Acrobat is available in the following websites:

http://www.cdms.net/ldat/ld4ES001.pdf

http://www.cdms.net/ldat/ld4ES025.pdf

Protégé: Protégé (azoxystrobin), manufactured by Syngenta, is a strobilurin fungicide with broad-spectrum activity. Protégé is a preventive seed treatment fungicide with systemic properties recommended for the control of several important plant diseases. It is registered for use to control seed-borne and soil-borne pathogens that cause seedling damping-off in sweet corn, cucurbits (cucumber), legume vegetables, and several field crops. Label information of Protégé is available at the following website:

http://www.cdms.net/manuf/1prod.asp?pd=6364&lc=0

M. Babadoost (217-333-1523, babadoos@uiuc.edu)

Fruit Production and Pest Management

Woolly apple aphid: A few growers reported greater-than-usual infestations of woolly apple aphids last year and have asked about their control this year. First, now is NOT the time to control woolly apple aphids, instead it's a good time to check out a couple of good fact sheets on this insect from Ohio State University and Cornell University on the web at:

http://ohioline.osu.edu/hyg-fact/2000/2208.html

http://www.nysipm.cornell.edu/factsheets/treefruit/pests/waa/wappleaphid.html

Woolly apple aphids winter either as nymphs in colonies on the roots of apple trees well below the soil surface or as eggs on elm trees (where any elms are still present). Colonies develop above ground on the branches, twigs, and shoots of apples, pears, quince, hawthorn, mountain ash, elm, and cotoneaster. Feeding on roots may cause enlarged galls and alter nutrient uptake and overall tree health ... root infestations are more damaging than above-ground infestations. Colonies feeding above ground produce honeydew that gives rise to sooty mold; they also may infest the cores of some apples, and they can be a nuisance to pickers.

Infestations often develop where carbamate or pyrethroid insecticides have destroyed populations of predators and parasites that otherwise provide some natural control. Growers are advised not to rely heavily on pyrethroids for control of other insects if woolly apple aphid has become a problem. The Cornell University fact sheet referenced above includes a list of apple rootstocks and their susceptibility or resistance to the root infestations by woolly apple aphid; MM.106 and MM.111 rootstocks are resistant. Insecticides such as Actara, diazinon, Provado, and Thiodan can be effective against summer infestations on branches and shoots, and increasing the volume of spray per acre increases the level of control they provide.

Another note on San Jose Scale: I received more comments on scale problems last year, so I'll repeat a comment for growers in the northern two-thirds of the state where bloom is not yet underway ... Good coverage with superior oil sprays applied from green tip through pink provide a great deal of scale control. Adding Lorsban, Supracide, or diazinon at green tip or any of these insecticides or Esteem at half-inch green to tight cluster can add to scale control at this time.

Petal-fall insecticides in apples generally target plum curculio; they are not usually key to codling moth control because codling moth egg hatch is usually not underway until a couple of weeks after bloom. To determine when sprays should include insecticides most effective against codling moth, hang codling moth pheromone traps in apple orchards during bloom, and time sprays according to degree day accumulations after the traps begin catching a few moths (the "biofix"). Follow label directions regarding timing according to degree days ... Esteem, Assail, Intrepid, and other alternative products recommend applications at 150 DD (base 50 F) after biofix; recommendations for organophosphates or pyrethroids generally state that 240 DD after biofix is about the right time for application. Codling moth eggs begin hatching about 240 DD after they are laid.

Eastern flower thrips? For plasticulture strawberry growers in the south where Sweet Charlie is already in bloom ... be sure to sample for eastern flower thrips in blossoms. The strong south winds of April 1-4 may well have transported this insect to us from the south. Open strawberry blossoms would be vulnerable if such transport occurred.

Grape flea beetle and climbing cutworms on grape buds: As grape buds begin to swell and open, growers should scout every few days for damage by flea beetle adults and cutworms. Either of these insects can destroy buds and therefore prevent new shoot growth. Sevin and Danitol are among the insecticides labeled and effective for flea beetle and cutworm control on grapes.

Rick Weinzierl (217-333-6651; weinzier@uiuc.edu)

Vegetable Production and Pest Management

Asparagus beetles: Be sure to scout asparagus for asparagus beetle adults and eggs. The threshold for treatment is 5-10 adults per 100 crowns or eggs present on more than 2 percent of the spears. See the 2003 Midwest Vegetable Production Guide for registered insecticides and rates; effective products include Sevin, Lorsban, malathion, Pounce, and rotenone.

Corn flea beetles in sweet corn: Just a reminder that corn flea beetles may be numerous enough south of I-70 to be problems as vectors of Stewart's wilt. Growers who purchased seed treated with Gaucho or Cruiser should expect control to be equivalent to about one greater level of hybrid resistance to this disease. Where susceptible hybrids are grown without using Gaucho- or Cruiser-treated seed, foliar applications of insecticides may reduce disease incidence. Scout frequently for flea beetles on small plants; based on work reported from New York and on Kelly Cook's M.S. thesis research here, the threshold for treatment is somewhere around 6 to 20 beetles per 100 plants. Where insecticides are used, be sure to scout again beginning 2 to 3 days later for reinfestations. Capture, Sevin, Lorsban, Asana, Warrior, and Pounce are among the insecticides that are labeled and effective against flea beetles in sweet corn.

Rick Weinzierl (217-333-6651; weinzier@uiuc.edu)

This issue's Words of Wisdom" ...

... on longevity ...

• It's really quite simple, the key to a long life is to keep breathing.
• For every man who lives to be 70, there are three women ... but by then it's too late.
• Humans are illogical creatures ... we wish for a long life but fear old age.

University of Illinois Extension Specialists in Fruit and Vegetable Production & Pest Management

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