"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@illinois.edu. To receive e-mail notification of new postings of this newsletter, call or write the same number or address.

In This Issue:

Upcoming Programs

Regional Observations (from Mike Roegge in western Illinois)

Notes from Chris Doll (thinning, historical notes on cicadas, Summer Horticulture Day)

Fruit Production and Pest Management (oriental fruit moth and codling moth updates, spotted wing Drosophila recommendations)

Vegetable Production and Pest Management (more on saturated soils, European corn borer and corn earworm; aphids, mites, and thrips in high tunnels)

Local Foods Issues (GAPS - water quality and disinfectants in postharvest handling)

University of Illinois Extension educators and specialists in fruit and vegetable production and pest management

Upcoming Programs

Check the Illinois SARE calendar for a full list of programs and links for registration.
http://illinoissare.org/ and http://illinoissare.org/calendar.php

Regional Observations

From western Illinois ... I don't believe there have been two consecutive years so different.  The Quincy Regional Airport has reported rainfall accumulation (from Jan. 1 to June 19) at 26" compared to 8" last year at this time (average is 16").  This past weekend some parts of eastern Adams county and western Brown county reported 8+".  I don't think anyone has seen the amount of erosion and soil movement we've seen this year.

All the rain and wet soils have created problems in getting plants/seeds established.  Succession plantings have been difficult and replanting has been common.  The rains on June 15 were accompanied by high winds that leaned over corn (both commercial and sweet corn), but by midweek most had righted itself.

My first planting of sweet corn (planted April 30) is beginning to show tassel in the whorl, and as I was scouting it I found European corn borer "shothole" feeding injury in about 75% of the plants. Pulling a few whorls I found 1st instar larvae.  (More on corn bores a little later in this issue.)

We still have more pumpkins to plant, as the wet soils have not lead to timely planting.  We sow rye in the fall and plant pumpkins into that.  We've found the rye helps control weeds and also lays down a barrier between the pumpkins and the soil so pumpkins are much cleaner in the fall.  However, rye also leads to other problems.  Four of the last 5 years we've had excessively wet conditions.  It's almost impossible to get soil to dry under the rye in a wet year.  Last year was excessively dry, and the rye used up most of the soil moisture reserves.  Neither condition is good.  Rye also greatly increases the risk of vole damage, but since there aren't many herbicide choices for pumpkins, the rye does help control some weed species.

Matted row strawberry production is starting to wind down, and after the final harvest, renovation should begin.  If dandelions are a problem, consider applying 2,4-D (it will not harm the strawberry plant if applied immediately after the last harvest, but you should be cautious if susceptible plants like tomatoes or grapes are nearby).  Wait 5 days after 2,4-D application and then mow off strawberry plants 1-2" above the soil.  Spread a complete fertilizer at the rate of 2# per 100' of row (or 40-50# of nitrogen per acre).  Use a tiller to narrow the plant beds down to no more than 16" in width. Wider beds don't produce any more berries because sunlight has a difficult time reaching the inner plants in a wide bed spacing.  There are several herbicides labeled for use at renovation in strawberry, including Dachtal, Prowl, Sinbar, and others.  Consult the 2013 Midwest Small Fruit and Grape Spray Guide.

Plasticulture strawberry harvest is complete, with yields higher than normal for us.  I believe this is due to the lateness of harvest, which allowed extra branch crowns to develop this spring.  We started picking Memorial Day this year (last year was May 1st).  We've never been able to get adequate branch crown development in our Labor Day plantings (maybe because of our northern location).  Because of the low yields we've carried over plantings for a second year of harvest.  We intentionally stress out the plants during summer to reduce branch crown development; we do this  mowing off foliage repeatedly and reducing water.

Red and black raspberry harvest has begun, and the first blueberries are now maturing on early varieties.  Cole crops are at harvest and early-transplanted vine crops have been flowering.

In the high tunnel, a few early tomato fruits are beginning to color.  Cucumber, zucchini, and green bean harvest has begun.  Aphids are beginning to show up, and I've seen one instance of mites as well.  We've always had aphids and/or mites in our tunnels and have had varied success in controlling them using insecticides/miticides.  This year we're going to try some biocontrol, using predator and parasitoid insect releases.  (More on biocontrol below.)

Mike Roegge (217-223-8380; roeggem@illinois.edu)

Notes from Chris Doll

Non-orchard travel has been my mode recently, and unfortunately no commercial orchards were included in the itinerary.  So ... observations in the Back-40 today show good growth of both fruit and shoots on all the tree fruits and a reasonable set of fruit too. A little hand thinning is needed, which will improve not only the size and quality of the survivors, but also improve the quality of the pack out by getting rid of both hail and curculio injury.  Few pests survived a minimal spray program except the curculio, but I will be looking for stink bugs of any kind while picking the brambles.  Some potato leafhopper injury was also noted, but stopped with a recent spray.

Black raspberries are at full harvest and thornless blackberries are looking good, with new cane growth up the top wire (which need to be tipped at a desired height to induce side branching). Grapes have set nice crop on nice sized clusters. The only negative on this crop is some phenoxy injury on shoot terminals, with the source being unknown.

It's time for Japanese beetle emergence, but my trap has not been set prior to this writing. It has been interesting for me to read about the periodical cicada emergence in some eastern and northeastern states and to see the photos of some skeletal accumulations under the trees. This pest is absent here this year, but I've watched growers battle them through several emergences. The one in 1967 was the worst, with bushels of skeletons under old apple trees. The use of pesticides to reduce adult populations and egg laying in orchards, renewal of old orchards, and planting in fallowed open ground free of inhabitation seemed to reduce the numbers in local orchards since that time.  During the last emergence, I advanced the idea of onion bags or other types of covers over new trees – the same idea floating row covers that allow photosynthesis to continue and are light in weight so that young shoots are not damaged. Chemical control has been easier, but for lack of that, the protection worked.

The Summer Orchard Day at Curtis Orchard near Champaign was well attended and worth the effort of all the Curtis family members present.  It is a great example of fine orcharding and marketing by all. That was followed by a tour of the University of Illinois Fruit Research Farm plots, which are yielding some good research data for many us in and around the state. Thanks to both groups.

Chris Doll

Fruit Production and Pest Management

Updates on Codling Moth and Oriental Fruit Moth

Oriental fruit moth:  Based on biofix dates of April 18 near Batchtown in Calhoun County and April 29 at Urbana,  degree-day accumulations (base 45F) since biofix for each location are ...

Location

Biofix Date

Degree-Days base 45F, through June 19

Degree-Days base 45F, projected through June 26

Degree-Days base 45F, projected through July 3

Calhoun County

April 18

1191

1406

1627

Urbana

April 29

1115

1322

1531

One location in far southern Illinois did not record consistent flights and a biofix until May 5.  This is likely the result of very low populations at that particular orchard.  Flight likely started in other far-southern Illinois orchards before that date.

Degree-day accumulations are taken from the Degree-Day Calculator program managed by the Illinois State Water Survey and the University of Illinois – see http://ipm.illinois.edu/degreedays/. 

Key sprays for second generation control should be timed to correspond with accumulations of 1,175 degree-days (base 45 F) and 1,475 degree-days after first generation biofix ... but always keep monitoring traps to observe flights in individual orchards.  Effective insecticides for oriental fruit moth control include Altacor, Assail, Belt, Delegate, Imidan, and Rimon; Entrust is effective in organic production (as is mating disruption, but because it simply prevents mating, it does not kill moths that have already mated or the eggs and larvae that result from those matings ... so since second-generation flight is already underway in most peach production areas, it's really a bit too late to start that approach). 

Codling moth:  Based on the biofix dates for the locations listed below, degree-day accumulations (base 50F) since biofix for each location (based on the closest regional weather stations) are ...

Location

Biofix Date

Degree-Days base 50F, through June 19

Degree-Days base 50F, projected through June 26

Degree-Days base 50F, projected through July 3

Murphysboro

May 4

877

1050

1229

Belleville

May 10

791

966

1149

Centralia

May 15

765

951

1140

Urbana

May 17

636

808

982

Lake County

May 19

484

633

782

Some key events in the codling moth's life cycle in comparison with degree-day accumulations (based on Table 6, p. 260, in Orchard Pest management, A Resource Guide for the Pacific Northwest, by Beers et al, published by the Good Fruit Grower in 1993) ...

Degree-Day Accumulations (Base 50 F)

First-Generation Flight

First-Generation Egg Hatch

Second-Generation Flight

Second-Generation Egg hatch

500

90 percent complete

54 percent complete

 

 

600

96 percent complete

73 percent complete

 

 

700

99 percent complete

87 percent complete

 

 

800

100 percent complete

95 percent complete

 

 

900

 

98 percent complete

1 percent complete

 

1,000

 

100 percent complete

5 percent complete

 

1,100

 

 

13 percent complete

1 percent complete

1,200

 

 

26 percent complete

3 percent complete

1,300

 

 

43 percent complete

10 percent complete

See the 2013 Midwest Tree Fruit Spray Guidefor listings of effective insecticides for codling moth control; they include Assail, Calypso, Altacor, Belt, Delegate, and Rimon.  Entrust and codling moth virus products are available for organic growers.  Again, see the Spray Guide for listings. 

Rick Weinzierl (217-244-2126; weinzier@illinois.edu)

Use Traps to Detect Spotted Wing Drosophila

Everyone growing blueberries, blackberries, and raspberries should be monitoring for spotted wing Drosophila, a new invasive pest that infests thin-skinned fruits as they ripen.  This invasive insect is known to be present in much of Illinois and will damage these crops severely, making the fruits unmarketable.  Peaches, tomatoes, and grapes also are suitable host plants. 

As I have noted previously in this newsletter, there is lots of useful information on this insect on a Michigan State University web site devoted to it ... http://www.ipm.msu.edu/invasive_species/spotted_wing_drosophila.  A section on monitoring includes instructions on how to make and use traps to detect this insect's presence.

Some simple instructions for making traps ...

  1. If you don't want to sort through the bait liquid described below, order some sticky yellow cards from Great Lakes IPM (800-235-0285).  Do this first so that they arrive in the mail by the time you've completed steps 2 and 3.  See page 25 of the online catalog ... a package of 25 3" x 5" cards sells for $8.75.  You will cut them in half, so 25 of them will allow you to run 5 traps for 10 weeks.  Order a larger number if you need more.
  2. Get and make the traps ... use 1-quart deli cups, preferably clear.  (Go to a supermarket with a deli, and if they will not sell you empty containers, buy some potato salad or whatever, and save the container and lid.)  Make at least 2 holes near the top of the container so that you can run wire or string through them to hang the containers.  Make at least 6 more holes along the side of the container at least 2-3 inches above the bottom ... these will let flies in.  The holes should be about the diameter of a number 2 pencil.  Use a paper punch or use a heated metal rod to burn through the plastic.  Hang half of a yellow sticky card (3" x 2 ½") from the lid.
  3. Prepare the liquid bait that draws fruit flies to the trap.  You can use apple cider vinegar or a mixture of ¼ oz. yeast, 4 teaspoons of sugar, and 12 oz. of water.  Pour the bait into the trap to a depth of about 1 inch. 
  4. Hang traps in the shade about waist high in area where ripening fruit is present. Check the traps and replace the bait liquid weekly and discard the old bait liquid away from the trap.  Use at least 2 traps for each separate patch or location for each crop.  Male spotted wing Drosophila fruit flies have a dark spot on each wing.  If you think you have detected this insect, send specimens to me or contact me by email ... Rick Weinzierl, 1102 S. Goodwin Avenue, Urbana, IL 61820; 217-244-2126, weinzier@illinois.edu.


Spotted wing Drosophila trap and adult male.

In general, insecticides that have short PHIs (preharvest intervals) and have been shown to be effective against spotted wing Drosophila include ...

Insecticide

PHI (days) in Blueberries

PHI (days) in Brambles

Days of Residual Activity

Malathion

1

1

5-7

Imidan

3

Not labeled

7

Mustang Max

1

1

7

Danitol

3

3

7

Brigade

1

3

7

Delegate

3

1

7

Entrust (OMRI)

3

1

3-5

Pyganic (OMRI)

(12 hours, REI)

(12 hours, REI )

2

Estimates of residual activity are adapted from work done by Rufus Isaacs and reported on the Michigan State University web site listed above.

Rick Weinzierl (217-244-2126; weinzier@illinois.edu)

Vegetable Production and Pest Management

More on saturated soils ...

As Mike Roegge explained in the last issue, saturated soils are prevalent in many areas.  To continue his discussion, let's talk about some more issues we will likely see this year as a result of excessive rainfall. 


Leaf yellowing (chlorosis) of tomato resulting from excess soil moisture (James Theuri).

Blossom end rot.  In general, most soils have sufficient calcium to support proper plant growth.  While proper liming will insure there is adequate calcium, it is not the lack of calcium in the soil that causes blossom end rot in most cases. It is the inadequate movement of calcium into plants that is the common culprit.  Anything that impacts root activity or effectiveness will limit calcium uptake.  This includes saturated soils (low oxygen limits root function).  Nutrient and water adsorption and their translocation are impacted; consequently, wilting, yellowing, stunting, and nutrient deficiencies are the most common symptoms associated with flooded soils with most vegetables.  See last week's issue for Mike Roegge's comments on nitrogen.  

Hormonal imbalances often occur when roots are in saturated soils, especially at cool temperatures, as production declines in the root-made hormones while stress/aging hormone production increases in other parts of the plant.  These shifts create serious imbalances in the levels, ratios, and timing of hormones, which results in abnormal plant development.

Soilborne diseases can be a major limitation to crop production, particularly for vegetables.  They are often difficult to control.  Fungal and bacterial pathogens are the most common pathogens that cause soilborne diseases.  Soilborne bacterial pathogens usually persist in the soil for only a short time.  Soilborne viruses that affect vegetables are few in number and generally survive only in the living tissues of the host plant or in the nematode or fungal vectors that transmit them.  Soilborne pathogens often survive for long periods on host plant debris, soil organic matter, or as free-living organisms.  Many soil factors including soil type, texture, pH, moisture, temperature, nutrient levels, and ecology affect the activity of soilborne pathogens. 

More than likely, symptoms of issues we will see this year are going to be varied and complicated.  What we might diagnose in the field as one issue may well be another.  Plant stresses, such as excessive soil moisture, make themselves evident in a number of ways.  There is always more than meets the eye.  A tremendous resource we have here in Illinois is the Plant Disease Clinic.  Don't hesitate to get them involved in helping diagnose a problem.  Visit the Plant Clinic web site to learn more.

Kyle Cecil (309-342-5108; cecil@illinois.edu) and James Theuri (815-933-8337; jtheu50@illinois.edu)

European Corn Borer and Corn Earworm

Mike Roegge reported infestations of European corn borer in his early plantings of sweet corn near Quincy.  This insect tunnels into an damages sweet corn ears, fruits of tomatoes and peppers, and a few other vegetable crops.  It overwinters here in the larval stage, pupates in late spring, and the first generation of moths fly and lay eggs in June in most years.  It is important to monitor and if necessary control this insect before silking in sweet corn, because larvae that tunnel into stalks may leave stalks and move into ears.  Controlling them then is more difficult.  Scout sweet corn by examining plants when the tassel is forming and just barely visible from above.  Look for shot-hole and window-pane damage on leaves.  Treat during the late whorl stage if 20 percent or more of the plants show larval feeding.  One application during late whorl, followed by additional treatments every 5 to 7 days until about 7 days before harvest provides adequate control of European corn borer.


European corn borer damage on leaves and larva in ear.

I'll reiterate (from previous issues) that traps in several areas have been catching low numbers of corn earworm over recent weeks as well.  Early sweet corn that is tasseling and silking ahead of all the field corn in an area will be THE preferred crop for egg-laying females.  If your trap has been catching any moths, be sure to manage this insect.  See "Preseason Reminders for Corn Earworm Management in Sweet Corn" in the February 20 issue of this newsletter for more information. 

Mites, Aphids, and Thrips in High Tunnels

As Mike Roegge noted, many who grow vegetables and small fruits in high tunnels experience increased problems with mites, aphids, and thrips.  In high tunnels, twospotted spider mite commonly infests tomatoes, peppers, cucumbers, brambles, and strawberries, especially day-neutral strawberries where plants are productive over several months.  Aphids – a range of species – become numerous on peppers and tomatoes, as well as leafy greens.  Thrips may build up on strawberries, brambles, and tomatoes. 

The 2013 Midwest Vegetable Production Guide lists the insecticides and miticides registered for use on specific crops for control of these pests.  Unfortunately, products widely used for control of "general defoliators" such as caterpillars and beetles are often not effective against aphids, mites, and thrips.  For example, pyrethroids are widely used on vegetables, but most are not very effective against aphids or mites, and because they natural enemies of these pests, infestations may even increase.  In some cases, very specific miticides and aphicides may be effective and labeled for use on the infested crop, but their use is impractical because the smallest available container may treat several acres and cost several hundred dollars – not a practical purchase for one high tunnel.  In addition, many growers do not use the same high-pressure, high-volume applications that might be used with larger equipment in outdoor fields.  The result is often poorer coverage and poorer control.  So ... what do you do about aphids, mites, and thrips in high tunnels?


Twospotted spider mites, aphids on tomatoes, and a typical plant-infesting thrips.

First, use the Midwest Vegetable Production Guide's listings of products that control these specific pests ... don't spray broadly toxic pyrethroids that are not listed to control them.  Products that generally are effective against aphids include Actara, Assail, Dimethoate, Fulfill, Movento, M-Pede (insecticidal soap), Orthene, and Platinum.  Products that generally are effective against twospotted spider mites include Acramite, Agri-mek, Oberon, Portal, and Zeal.  Products that generally are effective against thrips include Entrust, Radiant, and the pyrethroids (see individual crop listings).  Be sure to check product labels the listings in the Midwest Vegetable Production Guide for the specific products that can be used on specific crops.   

Effective control depends on very thorough coverage ... use enough water and pressure to get the insecticide spray to the parts of plants that are infested.

Insectaries (suppliers of beneficial insects) offer different predators and parasites that are natural enemies of specific pests.  For aphid control, releases of parasitic wasps that lay eggs into and kill aphids are most widely used.  For twospotted spider mites, other small mites that are their predators are used most commonly.  For plant-eating thrips, predaceous mites, predaceous thrips, and minute pirate bugs are the predators often recommended.  Suppliers (insectaries) who have worked with Illinois fruit and vegetable growers include BioBest (http://www.beesandbugs.com/ or http://www.mgshort.com/us/pest.php?id=10&name=Biological+Controls) and Koppert http://www.koppert.com/distribution-koppert-products/usa/).   Representatives from these companies will recommend certain natural enemy species and release schedules based on crop and pest combinations.  Remember that if you purchase natural enemies for biological control, applications of broad-spectrum insecticides such as organophosphates, pyrethroids, and most neonicotinoids will kill them, defeating the whole effort.

Rick Weinzierl (217-244-2126; weinzier@illinois.edu)

Local Foods Issues

Good Agricultural practices:  Postharvest Wash Water Disinfection

Some harvested commodities are washed in water dump tanks or by using spray washers.  While some processes re-use water for conservation, dirt, debris, and microbes can accumulate in the water.  Because of this, there are important steps that should be taken to ensure a relatively consistent and acceptable wash water quality.

Disinfection is the process of inactivating pathogenic microbes on surfaces and in water that will come in contact with edible parts of fruit and vegetables.  The goal of disinfection is to minimize the transfer of pathogenic microbes to fruit and vegetables so as to keep them safe for human consumption.  Disinfection aims to keep food-contacting surfaces and water 'sanitary'.

Chlorine is one of several disinfectants.  Others include hydrogen peroxide, ozone, ultraviolet light, oxidate, and peroxy-acetic acid.  For chlorine, there are several forms that can be used: chlorine gas, calcium hypochlorite, sodium hypochlorite and chlorine dioxide.  The most frequently used sanitizer in small farm settings is chlorine (similar but not identical to household bleach), and in an overall food safety program, it is effective.  In addition, it is cheaper than other disinfectants, easy to use, and may be used in any operation.  Chlorine is also relatively safe.

Chlorine is readily soluble in water and is a powerful disinfectant with oxidizing properties.  The most common form used is sodium hypochlorite salt (NaOCl) which releases the hypochlorite (the oxidizing molecule, also called the 'available chlorine') in the solution.  An oxidizing agent kills cells, and bacteria as single-celled organisms are readily destroyed by chlorine at a concentration of 100 to 250 ppm (about one pint of 12.5% sodium hypochlorite in 5 gallons of water.

The effectiveness of chlorine is affected by several factors:

Constant checking of the level of chlorine in wash solution is a necessity to ensure adequate wash water disinfection. Test strips are available and are cheap.  For surfaces which come in contact with produce, a 5% bleach solution should be used to disinfect them.

James Theuri (815-933-8337; jtheu50@illinois.edu)

Less Seriously ...

Sherlock Holmes and Dr. Watson went on a camping trip. As they lay down for the night, Holmes said: "Watson, look up into the sky and tell me what you see."

Watson said, "I see millions and millions of stars."

Holmes: "And what does that tell you?"

Watson: "Astronomically, it tells me that there are millions of galaxies and potentially billions of planets. Theologically, it tells me that God is great and that we are small and insignificant.  Meteorologically, it tells me that we will have a beautiful day tomorrow. What does it tell you?"

Holmes: "Somebody stole our tent."



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

Extension Educators – Local Food Systems and Small Farms

Bronwyn Aly, Gallatin, Hamilton, Hardin, Pope, Saline, and White counties

618-382-2662

baly@illinois.edu

Katie Bell, Franklin, Jackson, Perry, Randolph, & Williamson counties

618-687-1727

klbell@illinois.edu

Sarah Farley, Lake & McHenry counties

847-223-8627

sfarley@illinois.edu

Nick Frillman, Woodford, Livingston, & McLean counties

309-663-8306

frillma2@illinois.edu

Laurie George, Bond, Clinton, Jefferson, Marion, & Washington counties

618-548-1446

ljgeorge@illinois.edu

Zachary Grant, Cook County

708-679-6889

zgrant2@illinois.edu

Doug Gucker, DeWitt, Macon, and Piatt counties

217-877-6042

dgucker@illinois.edu

Erin Harper, Champaign, Ford, Iroquois, and Vermillion counties

217-333-7672

harper7@illinois.edu

Grace Margherio, Jackie Joyner-Kersee Center, St. Clair County

217-244-3547

gracem@illinois.edu

Grant McCarty, Jo Daviess, Stephenson, and Winnebago counties

815-235-4125

gmccarty@illinois.edu

Katie Parker, Adams, Brown, Hancock, Pike and Schuyler counties

217-223-8380

keparkr2@illinois.edu

Kathryn Pereira, Cook County

773-233-2900

kpereira@illinois.edu

James Theuri, Grundy, Kankakee, and Will counties

815-933-8337

jtheu50@illinois.edu

Extension Educators – Horticulture

Chris Enroth, Henderson, Knox, McDonough, and Warren counties

309-837-3939

cenroth@illinois.edu

Richard Hentschel, DuPage, Kane, and Kendall counties

630-584-6166

hentschel@illinois.edu

Andrew Holsinger, Christian, Jersey, Macoupin, & Montgomery counties

217-532-3941

aholsing@illinois.edu

Extension Educators - Commercial Agriculture

Elizabeth Wahle, Fruit & Vegetable Production

618-344-4230

wahle@illinois.edu

Nathan Johanning, Madison, Monroe & St. Clair counties

618-939-3434

njohann@illinois.edu

Campus-based  Extension Specialists

Kacie Athey, Entomology

217-244-9916

kathey@illinois.edu

Mohammad Babadoost, Plant Pathology

217-333-1523

babadoos@illinois.edu