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. 14, September 11, 2003

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"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:

Upcoming Extension Program (Illinois-Iowa Fruit and Vegetable Conference, November 13)

Crop Reports (from Elizabeth Wahle and Maurice Ogutu)

Notes from Chris Doll (weather and phenology, rain and fruit cracking, large apples, nitrogen for strawberries)

Fruit Production and Pest Management (yellowjackets, late season codling moth control, Asian multicolored lady beetle control)

Vegetable Production and Pest Management (vectors of pumpkin viruses, Leps in cole crops)

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

Illinois-Iowa Fruit and Vegetable Conference:

This annual Quad Cities meeting is scheduled for 1:00 to 5:00 p.m. on November 13, 2003, in Bettendorf, Iowa. Details will follow in later issues of this newsletter, but if you need additional information right away, contact Martha Smith, Horticulture Educator at the Macomb Extension Center, at 309-836-3366 or smithma@uiuc.edu.

Crop Reports

From southern and southwestern Illinois ... Just mentioning a lack of rain in the last newsletter seems to have acted as a modern rain dance. Rain fell throughout the region over Labor Day weekend in reported amounts of 3 to 6 inches. One of the most noticeable results was rain cracking of vegetable fruits and tree fruits, most notable being certain varieties of apple, peach, tomato, and melons. 'Honey Crisp' apple for example is one variety that will crack just prior to and during the harvest season after a rainfall, especially in the peduncle end. Greene and Weis presented an evaluation of 'Honey Crisp' at the 2001 International Dwarf Fruit Tree Association Conference in which they mentioned this tendency. To view the entire article, go to http://www.idfta.org/cft/2001/october/page100.pdf.

As a heads up, the Illinois Agricultural Statistic Service (ILSS) will be developing a new survey for specialty crop growers in Illinois. Currently there is limited information concerning specialty crops in Illinois, and it is hoped this survey will provide more complete information concerning the number of acres and growers of specific specialty crops. ILSS will be using their mail list to distribute the survey, and in addition the survey will (we hope) be available for the winter fruit and vegetable meetings around the state so that the maximum number of growers can be reached. In order for Illinois to receive grower assistance dollars and be competitive for grant dollars, it is important that input come from all specialty crop growers regardless of enterprise size.

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

In northern Illinois, day temperatures that were in the low 90s during the last week of August are now down in low 80s, and night temperatures are in the upper 50s and low 60s. Many areas in northern Illinois received about 1 inch or more of rainfall during the Labor Day weekend. Most of the pick-your-own orchards are now open to the public. Picking of summer apple varieties (Royal Gala, Jonamac, Ozark Gold, McIntosh, Cortland, and others) is going on in some orchards, while other varieties will be ready for picking by mid-September. Light incidences of sooty blotch and flyspeck have been reported in some orchards. Fall bearing raspberry picking and pruning of fruited canes of summer bearing raspberries are going on in many patches. Early grape varieties ready for harvesting, and some wine grape varieties will be ready very soon. There is some bunch rot in some varieties, and Japanese beetles continue to feed on grape leaves. Yellow jackets are also a problem in ripe raspberry and grapes at this time. There are some Asian multicolored lady beetles feeding on ripe fruits, but the population is much lower compared to same period last year.

Harvesting of sweet corn, tomatoes, peppers, muskmelons, watermelons, squash and other vegetables continues on most farms. Mosaic viruses are common in squash, pumpkins, turnip greens, and mustard greens, and diamond back moth larvae, cabbage loopers, and imported cabbageworm adults and larvae remain active in cole crops. Generally there is a very poor pumpkin crop this year in northern Illinois, although on a few farms pumpkin fruit is sizing well and in some fields more than 50% of the fruits are orange in color. Powdery mildew and downy mildew, two diseases that Mohammad Babadoost dicussed in the August 25 issue of this newsletter, are present in some pumpkin patches.

Maurice Ogutu (708-352-0109; ogutu@uiuc.edu)

Notes from Chris Doll

WEATHER AND PHENOLOGY: The lengthy dry spell that was discussed last time was broken by a very unusual and satisfying rain over Labor Day weekend. Reports of rainfall for this area ranged from 3.5 to 8.0 inches over a four day period, and it came without much noise or wind to disturb the fruit crop. Since an inch of water will moisten dry soil about 6 inches, we now have a little reservoir for the harvest season. Some soil samples were taken from a sandy peach orchard in an area that reported 4.5 inches of rain, and the water had penetrated to 36 inches.

One of the casualties of the extended rainy period was ripe apples such as Gala and Honeycrisp. Many Gala that were still on the tree suffered from stem-end split. My Honeycrisp tree which was 50 percent harvested and waiting for color, had 90 percent of the apples with rain cracks from ½ to 2 inches long.. In a recent Apple-Crop message, Dr. Jim Schupp of Cornell advised that this variety should be picked when the starch and color (creamy under-color) are right, rather than waiting for skin color. Some drought stressed Goldens also split.

The season continues to be advanced over average, but is about the same as the last two years. Jnathans can be called mature to ripe, and some Goldens are very close to harvest also. Peaches, except for the very late varieties, are finished, and Concord grape harvest is past peak.

APPLES: As mentioned earlier in the summer, apple size in some orchards is super. Jerry Mills was at the Farmers Market last week showing off the largest Jonathans he ever grew. In two Jersey County orchards on the 9th, Jonathan and Goldens were above normal in size, and lots of big Reds were seen also. So, the customers should not complain about little apples, but one grower reported this to be the case. Watching the big Jons go into the bin made me think that optimum handling and cooling will be needed to keep these apples in prime condition.

A brood of codling moth hatched out 8-16 days ago to cause more concern about this pest. No new entries were seen this week, but a few moths are being trapped yet. In 2001, I recorded new entries on September 14 in a couple of orchards. Dropping, particularly of Jonathans, has been reported in orchards without NAA sprays. It appears that any variety that has the tendency to drop is doing it. I have a variety called Hidden Rose that shelled off nearly 100 percent. Jonafree, Jonadel, and Jonalicious are other varieties that are hard to hold on the tree. It makes one appreciate Sansa, Gala, and Fuji with their sticking power. Color has improved immensely since the rain and will continue to improve as the apples mature in their time. However, even the best of coloring weather will not overcome some of the heat damage in late August. White rot (bot rot to some) has infected a few Goldens, and time will tell how severe it will become. The little red spots on Goldens means that the disease is present and a concern.

MISCELLANEOUS:

Strawberries benefitted from the rains, and more so if nitrogen had been applied before Sept. l. If not yet applied, there is still time to get the 35-50 pounds of N on to benefit the 2004 crop. And since the rain, I have seen both the fall grass and broad-leaved weeds such as chickweed, coming up.

A couple of new strawberry varieties have been introduced by New York. I have not seen them yet, but the B440 now named Ovation was fruited in 2003. It is one of the most vigorous plant makers that I have seen and gave an excellent yield of large berries. However, it is very late which could mean problems with heat in this area.

Raspberry and thornless blackberry shoots are growing vigorously. They can be trimmed enough to make passage through the planting possible and also to prevent tip layering that creates a mess of new plants. However, if new plants are desired, it is the ideal time to make a slit in the soil to poke the tip into, firming the soil around it with your foot.

Propagation wise, it is near the end of the budding season for apples and peaches.

ISHS HALL OF FAME NOMINATIONS are due soon. Make nominations to Bob Edwards at 815-569-2704 or to me at 618-656-1605.

Chris Doll

Fruit Production and Pest Management

Yellowjackets on ripe fruit

A yellowjacket

Maurice Ogutu noted a few problems with yellowjackets feeding on ripe fruit ... grapes, apples, raspberries, and late peaches are all among the treats these wasps like to eat as fall nears. By this time of year, populations of yellowjackets are increasing to their annual highs, and great numbers of workers from large colonies are foraging for food (including other insects and ripe fruit) to feed the nest's brood (larvae). Although baits and insecticide sprays can be used in attempts to reduce numbers, very little can be done to really control yellowjackets at this time of year. Timely picking, disposal of over-ripe fruit, screening to reduce wasp access to indoor market areas, and keeping all foods and drinks covered all help, but none of these steps will eliminate problems. Several people have reported that in areas of their market where they provide samples of apples or other fruit, they also scatter cucumber slices on those table tops and that the cucumbers seem to repel the yellowjackets. If you try this, please let us know if you see any benefit. Sprays of insecticides with short preharvest intervals (Sevin = 3 days apples, 7 days grapes; natural pyrethrins = 0 days) can reduce numbers a little bit in apple orchards or grapes where pickers would otherwise risk lots of stings, but such applications are rarely effective enough to offset costs and concerns about visible residues on fruits at harvest. After ripe fruit is abundant in orchards, bait buckets of insecticide-treated over-ripe fruit are mostly ineffective because they do not "out-compete" all the fruit still on trees for yellowjackets' attention. So ... no easy answers to reducing yellowjacket numbers in orchards or around markets.

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

Late Season Codling Moth Control

Traps in southern Illinois and Urbana (and I suspect northern Illinois as well) continue to catch codling moths, and these moths will continue to lay eggs that will give rise to larvae that will still enter fruits of late varieties. Where traps indicate egg hatch will occur before fruit is picked, codling moth control will still be needed, even in mid September. Insecticides that provide some degree of codling moth control and have short pre-harvest intervals include Assail (7 days), Imidan (7 days), and Sevin (3 days). Where codling moth injury occurred despite the use of Guthion, Imidan, diazinon, or Danitol earlier in the season, Assail would be the best choice for late-season control.

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

Asian Multicolored Lay Beetle as a Pest of Fruit

It's difficult to write a recommendation about using an insecticide to control a lady beetle, but controlling Asian multicolored lady beetles can be necessary. Adults of these aphid-eaters can and do feed on ripe, sugary fruit in the fall, and they can damage apples and grapes. In grapes, they may also become contaminants in wine. If control is necessary (and no, there's no established threshold for what constitutes "necessary"), insecticides with short pre-harvest intervals are the only options. Sevin, Imidan, Assail, or natural pyrethrins, all mentioned above in conjunction with yellowjacket or codling moth control, are possibilities.

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

Vegetable Production and Pest Management

Virus Diseases in Pumpkins and Other Cucurbits

Mosaic virus symptoms are widespread in cucurbits in northern Illinois. Growers there have asked about the likelihood that high numbers of soybean aphids may have contributed to spreading the disease so widely this season. I have not yet completed a thorough literature search on the vector capabilities of the soybean aphid, but a quick scan of some readily available sources would suggest that the answer COULD BE yes. The soybean aphid and other species in the genus Aphis are recorded as vectors of several viruses, and work completed recently in Wisconsin in Dr. David Hogg's lab confirmed that the soybean aphid can transmit cucumber mosaic virus from infected to previously uninfected snap beans. Look for more detailed information on the possible role of the soybean aphid as a vector of virus diseases of vegetables later this fall in this newsletter.

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

"Leps" in Cabbage and Other Cole Crops

Maurice Ogutu also noted that diamondback moth, cabbage looper, and imported cabbageworm were active in northern Illinois cole crops. Growers are reminded that diamondback moth is notorious for developing resistance to many insecticides. Where pyrethroids have been used a lot in the earlier portion of the season, it is very possible that control failures resulting from resistance might be seen on late crops at this time of year. Pyrethroids registered for use on cole crops include Ammo, Asana, Capture, Danitol, Pounce, Warrior, and Mustang. If infestations are not controlled by labeled rates of application of these compounds, it would be wise to switch to a different class of insecticide. Among the choices are Avaunt (high end of label rate), SpinTor, Larvin, and, of course, several products that contain Bacillus thuringiensis (Bt).

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

This issue's words of wisdom ...

State slogans that never quite made it to license plates:

Arizona: But It's a Dry Heat
California: As Seen on TV
Colorado: If You Don't Ski, Don't Bother
Connecticut: Like Massachusetts, Only Dirtier and With Less Character
Georgia: Without Atlanta we're Alabama
Idaho: More Than Just Potatoes... Well Okay, We're Not, But The Potatoes Sure Are Real Good
Illinois: Please Don't Pronounce the "S"
Indiana: 2 Billion Years Tidal Wave Free
Iowa: We Do Amazing Things With Corn
Kentucky: Five Million People; Seven Last Names
Maine: We're Really Cold, But We Have Cheap Lobster
Michigan: First Line of Defense From the Canadians
Minnesota: 10,000 Lakes and 10,000,000,000,000,000,000,000 Mosquitoes
Missouri: Your Federal Flood Relief Tax Dollars at Work
North Carolina: Tobacco is a Vegetable
West Virginia: One Big Happy Family -- Really!
Wisconsin: Come Cut Our Cheese
Wyoming: Wynot?

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

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