Welcome to the University of Connecticut Cooperative Extension System's
Vegetable Pest Message.
This message is being recorded on Friday afternoon August 22 by Jude Boucher.

This week's message will cover:

Upcoming Educational programs
On Thursday, September 18, there will be a day-long session on using Biological Control in Greenhouses at the Sturbridge Host Hotel.  The session will cost $35 and have 4 pesticide re-certification credits.  Contact Leanne Pundt at 860-626-6240 for more information. 

On Monday, December 1, there will be another opportunity for you to learn more about Zone Tillage and How it Affects Soil Health.  This meeting will also be conducted at the Sturbridge Host Hotel.  We will have researchers from Cornell and growers who are using zone tillage speak and I will present the results of the soil survey I have been conducting around CT this summer. Cost has not yet been determined. Contact, yours truly, Jude Boucher, for more information at 860 875-3331.   

On Thursday, December 4, there will be a day-long conference on Renewable Energy for Farms and Greenhouses.  This will also be at the Sturbridge Host Hotel.  For more information contact Tina Smith at 413-545-5306. 

Finally, on Thursday January 22, we will host the Annual Connecticut Vegetable and Small Fruit Growers Conference here at the Tolland County Extension Office.  Contact Jude for more information.

 We'll also get you more information on these December and January Meetings in the next issue of Crop Talk.

Downy mildew in Connecticut
On Wednesday, August 20, we found downy mildew on cucumber plants in Berlin and East Hartford, CT.  It was also detected the same day on butternut squash in East Windsor.  This must have arrived on Monday=s storm.  Since DM will usually defoliate plants in as little as 7-10 days, all growers should protect their cucumber, melon and winter squash crops with an effective fungicide at this time.  As of yet, there has been no report of DM on pumpkins, and I scouted quite a few acres this week, so this crop may not need protection.  The materials that seem to be working the best in neighboring states include Ranman, Previcur Flex and Tanos.  However, we had a strain that only affected cucumbers and melons last year and many inexpensive materials such as ProPhyt and maneb were effective. There is a 5 day-to-harvest restriction on maneb products. Remember to re-scout your field 4-5 days after treatment to be sure that the material you applied is working.  If not, switch to a different material and spray again immediately.  DM is easy to spot on cucumbers and melons.  It first affects the oldest leaves before moving to young leaves, and appears as yellow or brown squared-off lesions about 1/4-1/2 inch in size, that are restricted by the small leaf veins.  Organic growers may be limited to using copper sulfate.  The UMass folks report that both the products Basic Copper 53 and NuCop 50WP are OMRI approved for organic growers.  For more information, check the New England Vegetable Management Guide   

Corn earworm
The number of CEW moths in pheromone traps ranged from a low of 1.5 per night in East Lyme to a high of 33 per night in Shelton.  Most folks captured high counts on Monday, but by Tuesday the traps at these sites had settled down to moderate levels putting most growers on a 4-day spray schedule on fresh silking corn this week. Between 1.5 and 9 moths per night were captured in East Lyme, Northford, Berlin, Glastonbury and Storrs, and at a second trap across town in Shelton.  East Hartford was just over the 3-day schedule threshold at 13.5 moths per night.  The trap with 33 moths/night in Shelton was checked last Monday, so is probably at lower levels now.

Here are the CEW thresholds: 

moths per night   recommended spray interval
0-0.2   No spray
0.2-0.5   6 day schedule
0.5-1   5 day schedule
1-13   4 day schedule
>13 moths   3 day schedule

Fall armyworm infestations
Traps in Shelton and East Lyme captured 3 and 5 FAW moths for the third week in a row, while the trap in East Hartford was empty.  Both whorl and pre-tassel stage plantings in Shelton and East Lyme required treatment this week as pre-tassel stage fields had 14-16% of the plants infested with FAW caterpillars, and mid-whorl stage plantings were at 50%.  Continue to scout your young corn for this pest and treat if pretassel stage fields are over 10% infested.  This week I was able to show two growers who did not spray a pre-tassel stage field on-time, that the caterpillars had moved from the expanded tassel down to the ear and infested the end, just like corn earworm.  However, unlike corn earworm, it is too late to get the FAW larvae out with silk sprays. One grower had poor control with Warrior at pre-tassel and also had a FAW infestation at silk.  Remember that SpinTor, Avaunt and Intrepid will provide consistent control of this pest and spare natural enemies.   

European corn borer 
Trap counts for ECB crashed at all locations this week.  Traps in Shelton, Berlin, Northford and East Hartford all captured less than 3 moths. I think the second generation corn borer flight is over and it is safe to stop spraying peppers at this time. 

Here is a list of infestations found at different sites while scouting sweet corn this past week. *means that the planting is over threshold and should be sprayed. MW=mid-whorl, LW= late-whorl, PT=pre-tassel, S=silk. 

Town % infested plants Stage of planting ECB  & FAW moths / week CEW moths/N
Shelton 14%* FAW
24%* FAW
50%* FAW		 PT
LW
MW		   3 ECB, 3 FAW 33 = 3-day schedule
3 = 4-day
Northford       0 ECB 6 = 4-day schedule
East Lyme II 16%* FAW
16%* FAW		 PT
LW		   5 FAW 7 = 4-day schedule
Berlin 0% PT   0 ECB 7 = 4-day schedule
Glastonbury       9 = 4 day schedule
East Hartford 0% PT   1 ECB, 0 FAW 13.5 = 3-day schedule
Storrs       8 = 4-day schedule

Tomato fruit worms
The corn earworm is also known as the TFW.  Normally it only bothers our tomatoes when we are capturing over 30 moths/night in our corn traps and there are no corn plantings with fresh silk left around our tomatoes.  However, this week we found TFW in the tomatoes on several farms around the state with fresh silk close by and relatively low moth numbers in traps.  The caterpillar has a light tan head capsule and light colored stripes down the side of its body.  The higher rates of selective materials such as SpinTor, Avaunt, Intrepid, Proclaim or a Bt product will control TFW on tomatoes, without getting you into problems with aphids.   

Bacterial canker and powdery mildew on tomatoes 
Bacterial canker appears on lowest leaves first as dark lesions along the margins of the leaves.  Several farms have tomatoes with canker at this time due to all the wet weather.  This disease is usually seed borne but can survive between years on stakes, old crop residue and reused plastics.  It can be tough to rid a farm of this disease once you have it, even when taking the proper sanitary precautions, such as dunking all stakes in a chlorine bath, switching tomato varieties and sanitizing greenhouse surfaces.  At this point in the season, growers with canker on their tomatoes should add copper to their early blight or leaf spot sprays.   

I found the first case of powdery mildew on tomatoes this year on the All-America Selection Trial garden up at the research farm in Storrs this week.  Yes, researcher=s plants get diseases too!   Materials that help manage powdery mildew on tomatoes include Nova, Cabrio, Rally and sulfur products like Microthiol Disperse.  These products can all be used on the day of harvest.    

That=s all for this week.  This message will next be updated in on Friday afternoon August 29.

Jude Boucher

 Previous Vegetable Pest Messages - 2008
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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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