We now have six farms in Connecticut  and Massachussetts that have converted to deep zone-tillage (also known as vertical tillage) to help protect and improve soils on their farms. What all of these growers are most pleased about, is how fast they can prepare a field with their new machine. One grower estimated it reduced his field preparation time prior to planting on a large piece from 18 hours to 5 hours. Another grower estimated he could prepare a one acre field for planting in 30 minutes with a two-row Zone Builder (15 minutes with a 4 row machine). How does that compare with what you are currently doing with a plow, harrow and cultipacker?  I think faster prep time will ultimately be what popularizes these machines in our area, since another grower in Hadley, MA said he had 5 neighboring growers stop to ask about the new machine the first time he had it in the field.  I think once you guys see a neighbor prepare his fields in less than a third of the time that it takes you to do it, you might start asking yourselves, what am I doing wrong?  Those of you who attended the twilight meeting last year at the Cecarelli Farm already know that this is true.  I have made it out to all of these farms to conduct Cornell Soil Health Tests so that we can document soil health indicators before they use their new reduced-tillage machines. This will help us document the changes that take place in organic matter, soil structure, root health and other indicators over time.  If you buy a new vertical till machine, let me know and I will try to get out to conduct Soil Health Tests on your farm.   

Ordering insect traps and pheromones
If you plan to monitor for both European corn borer (ECB) and corn earworms (CEW) in your sweet corn this summer you will need at least 3 Scentry Heliothis traps, a pack of 10 Hercon brand CEW lures and 5 of each type ECB lures (both E & Z lures) .  Store the lures in a zip-locked bag in your freezer until they are needed.  It is important that you get the Hercon brand lures for your CEW lures because the thresholds that we use to tell you how often you need to spray are based on the emission rate of this type of lure. Other lures will catch moths, but they won't tell you what spray schedule you should be on. Set up your CEW traps just before your first sweet corn planting develops silk.  Great Lakes IPM in Vestaburg, Michigan, carries the Hercon brand CEW lure and other IPM supplies, and has low prices.  Some better-known companies do not carry Hercon brand lures. You can reach Great Lakes IPM at 1-800-235-0285 or check their web site at www.greatlakesipm.com  

Before ordering your pheromone lures, you should check the tops of your old traps to make sure the mice didn=t chew holes in them while trying to get to dead insects inside over the winter.  Replacement tops for your Scentry traps are only about $17. 

Fall Armyworm (FAW) can be monitored with a $10 green Universal Moth Trap and 3 to 4 FAW lures. You will also need a Vapona (DDVP Vaportape) killing strip for your FAW trap.  FAW traps tell you that the moths are in the area and when it is time to scout your corn for larvae. Any brand lure will do for monitoring ECB or FAW.   Keep your unused lures in the freezer until they are needed (but not the killing strip).  Replace the lures on your traps every three weeks.  Again, that number for ordering supplies from Great Lakes IPM is 1-800-235-0285.     

Row covers to prevent early insect pests
Here is a list of some of the insects that you may wish to exclude using floating row covers in your mixed vegetables: flea beetles on salad mixes, eggplant or brassica crops; Colorado potato beetles from your eggplant, tomatoes or potatoes; leafminers from your spinach and beet greens; root maggots from your radishes; and leafhoppers from your early snap bean plantings.  Some crops such as mesclun salad greens and radishes will need to stay covered until harvest, but solanaceous crops can be uncovered by mid-June.  Beans can be uncovered after buds form and before flowers open.

Summer cover crops
You can use summer cover crops to help build organic matter levels, loosen hard soils and reduce root-knot nematodes.  Think about using summer cover crops either after an early short-season crop like peas or lettuce, before a late planted cash crop, or for the whole season to rest a field and improve fertility.  Sorghum-sudangrass is best to help build organic matter, loosen soil and control nematodes but buckwheat can also help improve soil structure and is the better choice for suppressing weeds as it establishes faster.  These cover crops can be planted from June through August. Use 30-50 pounds/A of sorghum-sudangrass or 40-100 pounds of buckwheat seed per acre. Kill the buckwheat at bloom or before seeds form to avoid volunteer plants.  Mow both these cover crops after about 40 days.  For sorghum-sudangrass, let it re-grow and flail mow again at 60-70 days before incorporating and planting a winter cover crop.

Perimeter trap cropping for cucumber beetle control
One of the best ways to control cucumber beetles on summer squash, cucumbers, melons, butternut and acorn squash is to use perimeter trap cropping.  To use this technique, simple plant 1 to 2 rows of Blue Hubbard squash all the way around your main crop.  Remember you need the Blue Hubbard trap crop on all 4 sides of the field for the system to work.  The idea is to protect the seedling plant from direct damage by the beetles and to prevent the spread of bacterial wilt, which is primarily vectored to the plants before the 5 leaf stage.  To do this, we use the trap crop and border sprays to create a poisoned fence.

The trap crop has to emerge at the same time as the main crop and has to stay healthy up until at least bloom.  So, plant the trap crop on good ground, not in a compacted roadway or drainage ditch where it might not emerge or the seeds may get washed away or drown.  Some folks plant the trap crop on the edge of the outer row of plastic mulch and remove it at bloom, so it doesn=t interfere with the main cash crop.  To keep the system simple, use the same in and between row spacing as your main crop.

Spray the trap crop as soon as the first beetles appear and begin to feed.  Don=t wait for the beetles to get on the main crop...spray early to create a poisoned fence.  Monitor the field on a weekly basis and make 1-2 additional sprays if more live beetles are found on the perimeter plants.  Growers that have used this system in the past have found that it is actually easier to use than multiple full field sprays, it gave them better cucumber beetle and bacterial wilt control, it dramatically reduced their pesticide use, and improved their crop yields. They all thought that the PTC system saved them money.  PTC may also help prevent the spread of other diseases by cucumber beetles and prevent the build-up of aphids and other secondary pest problems caused by insecticide use.

Many of the growers wholesaled the Blue Hubbard for $7-8 per banana box (2/box) or simple retailed them from their stand.  Most growers are surprised to find that they can sell Blue Hubbard squash.  You could also offer them as part of a Halloween display: for instance, a pumpkin, blue hubbard, and bundle of corn stalks for $20.  Give it a try, PTC is much easier to do than it sounds!  If you prefer to try another Cucubita maxima variety as the trap crop, I would suggest butter cup squash. There is a good market for butter cup and it works almost as well as the Blue Hubbard.

Perimeter trap cropping can also be used to control pepper maggots in bell pepper plantings by surrounding the block with one or two rows of hot cherry peppers as a trap crop.  In July when pepper maggot stings or shallow depressions are detected on the surface of the cherry pepper fruit, treat just the trap crop with an effective insecticide like Orthene or Dimethoate.  

Colorado potato beetle management
Adult Colorado potato beetles (CPB) are out and on tomatoes, eggplant and potatoes on some farms. The most important alternative control you can employ for this pest is crop rotation.  If you rotate your solanaceous crop to a field as little as 1/4 mile away you will delay colonization and reduce the number of beetles by over 90%.  If you only have one field, rotate your susceptible crops from one side of the field to the other, and plant two rows of potatoes between the new and old plantings as a trap crop.  You can treat the trap crop at planting with a nicotinoid insecticide like Admire or Platinum, or wait until the beetles arrive and treat the foliage with one of the products listed below.  Another great preventative practice is to strip-till through a killed, rye cover crop residue.  Potato beetle damage is dramatically reduced by organic mulches because most beetles walk to the crop from overwintering sites, and the mulch impedes their progress and increases the number that perish to disease.  Planting after 15 June is also suppose to reduce the number of beetles because most emerging adults should have already dispersed and found a host plant by then. 

Spray potatoes if you find more than 0.5 beetles per plant, 4 small larvae per plant or 1.5 large larvae per plant.  Mid-sized and late-season potatoes can tolerate 20% defoliation without affecting yield.  Spray eggplants between seedling and fruiting stage if you find more than 1.5 adults, 2 small or 1 large larvae per small plant (<6"), or 4 small larvae or 2 big larvae for plants over 6" in height. 

This pest will become resistant to any chemical in as little as 3 years, and there are already Admire and SpinTor-resistant populations in neighboring states. It is important to remember your resistance management training when spraying for this insect. You can use the same product 2-3 times in a row on one generation, but you need to rotate to a different chemical group with a different mode of action for the second generation in late July and for the next year.  If you do a good job cleaning up the first generation, usually there is no second generation in July to worry about.

• Group 4, the nicotinoids, such as Actara, Admire, Assail, Cruiser, Goucho, Provado, Platinum, and Venom;
• Group 5, spinosad-type products, such as SpinTor, Entrust or Radiant
• Group 6, abamectin products, such as AgriMek and Abba, (larvae only)
• Group 9B, cryolites, such as Kryocide, Prokill and Cryolite (larvae only)
• Group 11, Bt products, such as Novodor (larvae only)
• Group 16B and 17, insect growth regulators, such as Rimon and Trigard (larvae only)
• Group 18, azadirachtins, such as Neemix and Azatin
• Group 26, indoxacarb, know as Avaunt (larvae only)

Remember that the synthetic pyrethroids are very hard on beneficial insects, which help keep secondary pests in check. Use these and other broad-spectrum insecticides only as a last resort for CPB. 

Phytophthora Prevention and Management
If you grow cucurbits, solanaceous crops or beans, one of your missions in life has to be to prevent water from standing in your fields. Water management is the key to Phytophthora control.  By eliminating the standing water, you can often prevent the disease cycle from starting in your crops, which is the only way to stop this disease from causing extensive damage. The resting spores of this disease only become active if they have 24 to 48 hours of standing water and are in the presence of a susceptible host crop. Water management is particularly important if you are using plasticulture where the raised beds can cause water to pool like a dam every 5 feet across your field.  

Phytophthora management begins with sanitation, proper site selection and crop rotation. Do not compost rotten fruit and vegetables from your retail stand in your field.  This is often how Phytophthora gets introduced from another farm. If you borrow equipment, clean the soil off the wheels, plows and coulters with a pressure cleaner before taking them into your fields to prevent introducing spores.  If infested fields drain into irrigation ponds, do not use these same ponds to irrigate clean fields.  Don=t plant susceptible crops like cucurbits, peppers, eggplant and tomatoes and beans back-to-back, rotate them with other plant families, especially sweet corn.  Next choose a field with good water drainage for susceptible crops...not a low wet field where the water has nowhere to go. Sometimes it even pays to level the field with a front end loader or to fill low lying areas to prevent standing water.  Before planting, chisel plow or V-rip the field to break up any existing plow-pan that may have formed to allow water to penetrate deep into the ground.  Then, orient your beds so that the water will run down slope and out from between the rows.  You may also have to remove the soil from between the raised beds at the ends of each row to allow the water to leave.  Use a bed-maker that will create a domed-shaped bed so that it will shed water away from the plants.  The beds should be at least 8 inches high to help get the plant roots up out of the wet zone.  Inspect all irrigation lines for leaks the first time you turn them on to help prevent pooling water.  Don=t plant in low Awet holes@ where you know the water will pool sometime during the season...that is where the disease cycle will begin.  Break the beds in the low valleys to allow water to leave the field by flowing through the beds.  Just leave the T-tape hanging in mid-air where you create the drainage ditch through the beds.  After you transplant, chisel-plow or V-rip between the beds early in the season to help with water penetration after major rainfall events.  If Phytophthora starts in one area of the field, remove the infected plants and a few healthy-looking plants around them in all directions to help prevent ariel spread of the disease. Also, remove any soil barriers or dams in low spots at the edge of cultivated fields so that water can leave the field and not back up into the planted area.  This may seem like a lot of expensive work, but compared to ignoring the standing water and letting Phytophthora have its way with your crop, water management is cheap, and it works!

That's enough for this week.  This message will be updated next on Friday afternoon June 11th. 

Jude Boucher

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The information in this material is for educational purposes. The recommendations contained are based on the best available knowledge at the time of printing. Any reference to commercial products, trade or brand names is for information only, and no endorsement or approval is intended. The Cooperative Extension system does not guarantee or warrant the standard of any product referenced or imply approval of the product to the exclusion of others which also may be available.All agrochemicals/pesticides listed are registered for suggested uses in accordance with federal and Connecticut state laws and regulations as of the date of printing. If the information does not agree with current labeling, follow the label instructions. The label is the law.Warning! Agrochemicals/pesticides are dangerous. Read and follow all instructions and safety precautions on labels. Carefully handle and store agrochemicals/pesticides in originally labeled containers immediately in a safe manner and place. Contact the Connecticut Department of Environmental Protection for current regulations.The user of this information assumes all risks for personal injury or property damage.Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture. Kirklyn M. Kerr, Director, Cooperative Extension System, The University of Connecticut, Storrs. The Connecticut Cooperative Extension System offers its programs to persons regardless of race, color, national origin, sex, age or disability and is an equal opportunity employer.

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