Organic Integrated Pest Management in High Tunnel Vegetable, Small Fruit, and Flower Production

Organic Integrated Pest Management in High Tunnel Vegetable, Small Fruit, and Flower Production

Summary

High tunnels are low tech and inexpensive unheated plastic greenhouse structures that allow for production of extended season, higher quality and greater yielding vegetables, small fruit and flowers. Organic production in this environment benefits from reduced disease pressure, as well as the potential for enhanced prices. Cost effective, safe, and practical methods to control pest pressure in these structures are being researched and evaluated. Field events will be held at on-station and on-farm locations and will allow multi-disciplinary team members to engage with producers. Extension programming is being addressed with a range of educational materials and outreach activities.

Objectives/Performance Targets

Research objectives:

Evaluate three organic IPM techniques on selected high tunnel crop production systems in on-station trials at four sites–

Double-cropping annual strawberry and vegetable production systems – Wichita, Kansas

Organic and conventional production systems for green leafy vegetables – Olathe, Kansas

Flower-based production systems – Mead, Nebraska

Extended-season production of warm-season crops – Columbia, Missouri.

[Organic IPM techniques include use of beneficial attractant perimeter crops, release of beneficial insects, and use of OMRI approved control products for pest problems.]

On-farm Objectives:

Evaluate organic IPM techniques identified through the research, or of current importance. An economic analysis will be preformed on the IPM techniques assessed positively by the grower-collaborators.

Accomplishments/Milestones

Please see 2005 Annual Report for activities prior to 2006.

The Great Plains Vegetable Growers Conference held in early January of 2007 had a high tunnel workshop with over 100 attendees. Five collaborators (discussed below) comprised the popular ‘farmer panel’ that was been the late afternoon session of the high tunnel workshop (as in prior years this closing has been popular). They each described their results at that time.

University of Missouri at Columbia-
Research was concluded by 2005 and is reported in the 2005 Annual Report.

Kansas State University-
Research was concluded by 2005 and is reported in the 2005 Annual Report. Interpretation of some of the 2005 results is under review and will be in the forthcoming final report.

A field day in late July of 2006 featured IPM a discussion on some of the research and collaborator work during a high tunnel tour held after the classroom presentations. More then 25 individuals were present during this tour stop.

University of Nebraska at Lincoln-
Their research continued through 2006. (see the 2005 Annual Report for specifics) Data was collect throughout the year. Interpretation of the results is under review and will be in the forthcoming final report.

Impacts and Contributions/Outcomes

Five collaborators were identified to evaluate organic techniques or tactics for pest control in 2006. They were asked to record the following information is typically recorded for pesticide applications and beneficial insect releases:
– crop treated, it’s growth stage, and amount, if any, damage from the pest;
– the pest or pests, how numerous, and stage of development (e.g. nymph vs adult);
– date and time of application;
– product applied, the rate used, the amount of mixed material applied, and the approximate area to which it was applied;
– finally, a follow-up evaluation on the effectiveness of the material, which will depend on the situation, and may be from the next day up to up to several weeks later.

Collaborator with cut flower production:
1) Use of two different biofungicides to control root rot on high tunnel cut flowers. You have Companion and Plant Shield to test on Delphiniums. Since Companion is applied as a liquid drench, you also have two injectors (Young Mixer Proportioner; Add It Proportioning Fertilizer Injector) with which to try and compare for functionality.

2) Evaluation of several insecticides for control of insect pests. The following pests (and products for testing) are anticipated and could be tested: thrips (Conserve; Pyganic & Neemix); sunflower head weevil (Pyganic & Neemix); various caterpillars (BT; Conserve).

We understand that sometimes the pest does not show up on a given year, or that a sufficient amount of crop area may be available for effective testing. However, to aide in testing quickly and effectively, a Rocket Electric Sprayer is being provided, and feedback on its usefulness is expected.

3) Use of insect screening for reducing grasshopper damage. The insect screen Econet B has been purchased for this purpose. It would screen out new populations of grasshoppers from entering the high tunnel. To control any nymphs that may hatch out in the high tunnel, Pyganic with and without Neemix could be evaluated for their control.

Result (summary)-
1) The producer felt both biofungicides provided some benefit, as it seemed they had less disease problems. Rootshield was easy to work with as a preplant incorporated product. Companion mixed up easily, and of the two injectors, they had more confidence in Add It, but both were easy to work with and acceptable. The Young Mixer was probably more well suited to smaller application.

2) The producer loved the Rocket Electric Sprayer and noted that due to the ease of application they got to their pest control duties more timely and had better control. They noted that not having to carry around a backpack sprayer on a post 50 year old back probably makes the price cheap compared to back problems. Lastly the long hose made negotiating into difficult areas easier. Pyganic, Neemix and B.T. were all used and seemed to work for the pests they treated for, blister beetles & leaf scraper, aphids, and tiny (sunflower?) headworm, respectively. They did not have enough pest pressure to do comparative treatments.

3) Econet B continued to work well in screening out large grasshoppers and cucumber beetles. Any small grasshoppers or cucumber beetles that got inside were controlled with Pyganic. The crops they grow in tunnels with Econet B can accept the higher temperatures it creates, by reducing wind through the tunnel. It has a secondary benefit in that the cut flowers do not lodge.

Collaborator producing roses (with minimal pesticide use):
1) Use of one biofungicide (Sonata) to control powdery mildew on high tunnel roses – anticipating comparison of its performance to baking soda.

2) Use of predator mites for control of spider mites on high tunnel roses. Will receive five shipments of Phytoseiulus persimilis (2,000 each) from Hydrogardens in the following schedule: two for March, then one each in April, May & June. Suggest you use a hand lens to view the predator mites prior to their release. These will aide in recognizing them on your plants. Please follow the beneficial insect release instructions included with the shipment. Will also receive Floramite, a new insect growth regulator that is effective against two-spotted (and similar) spider mites while not harming predator mites. This is a back-up in case the predator mites do you provide adequate control, and should allow achieving pest and predator mite balance.

Result (summary)-
1) Compared Sonata to baking soda to control powdery mildew. Sonata worked better and left no residue. Sonata also seemed to cure as well as prevent.

2) They released the spider mites and did not have any problems with spider mites that season. Could see the spider mite predators, they were orange, and moved fast. They could never find 2 spotted spider mites on the roses the entire season. Grower would release on their own next year. Whether that was a ‘this year fluke’ or the result of the predator release, they could not be sure, but given past problems, felt there must be some credit. Due to no spider mite problems, they were not able to use the Floramite. However, they also work with an adjoining nursery and the report is it has worked well when used there.

Collaborator with tomato and greens production using beneficial insect releases:
1) Use of organic insecticides to control harlequin bugs on high tunnel kale. I anticipate you will compare Pyganic, Neemix and Pyganic & Neemix in combination.

2) Use of predator mites for control of spider mites on high tunnel tomatoes. You will receive nine shipments from Hydrogardens in the following schedule: two each for April & May, then one each from June through October. I strongly suggest you to use a hand lens to view the predator mites prior to their release. These will aide you in recognizing them on your plants. Please follow the beneficial insect release instructions included with the shipment.

3) Use of Trichogramma to reduce the incidence of Cole crop caterpillars and tomato fruitworm. Since adequate control of these pests are not likely, you will probably have to supplement with BT applications. You may find use of Neemix and/or Pyganic worth considering as well.

Result (summary)-
1) Did not end up trying to control harlequin bugs in high tunnel because they had a planting right behind in the field that did not have any problem. Harlequin bugs did show up, and did kill off the kale, but when they waited long enough the swiss chard recovered as the harlequin bug population fizzled.

2) Released spider mite predators as scheduled through the season, but had a problem in July. Corrective action was Mite-X (OMRI approved) twice a week for 2 weeks and then they did a double release. Then the mite pressure seemed to decline and the plants resumed fast enough growth to be OK. Looked for spider mite predators at release and could find, but once were on the plants they had a difficult time telling the difference. May try next year to see if they work again. Otherwise they would probably just plant and spray Mite-X if they had trouble. [Growth was very thick and may have been too hot, so (next year) they will put less plants & spray instead.]

3) Trichogramma were easy to release, but they did not feel like there was any reduction in caterpillar population. They had plenty of tomato fruitworm in the fall high tunnels.

4) Installed Home Depot insect screen in the greenhouse ‘as a tent’ which did keep the cucumber beetles off the cucumbers, but they had troubles with aphids on the cucumbers. The aphids were controlled with ladybugs and Aphidius, but yields were low (fruits kept aborting). Field cucumbers planted in white plastic and with floating row cover worked quite well.

Collaborator with tomato and greens production using a high pressure sprayer:
1) Use of organic insecticides to control harlequin bugs on high tunnel kale. Compare Pyganic, Neemix and Pyganic & Neemix in combination.

2) Use of BT to control tomato fruitworm in high tunnels, with the aide of a high pressure sprayer. You may find use of Neemix and/or Pyganic worth considering as well. Since the principle question here is whether the use of the high pressure sprayer makes a significant impact of pest control (and labor needed for application) everything you can do to more fulle document this would be helpful. Three things to consider are: a) leaving a couple of tomatoes untreated in each high tunnel, b) applying BT with the same sprayer you have in the past, and c) use of the high pressure sprayer for some field applications as well.

Result (summary)-
1) On harlequin bugs tried row cover, Pyganic, and Pyganic & Neemix- nothing worked.

2) Insect screening worked well for tomato fruitworm and tomato hornworm. Had almost no incidence. But the aphids quite bad April into July. But the tomato crop followed some salad greens & herbs.

3) For the unscreened greenhouse they did get control with BT and the high pressure sprayer and did observe the caterpillars with blackened guts. Sprayed about every 2 weeks with copper, fish emulsion and BT. The sprayer was much faster. Compared to the tractor sprayer the droplets were much smaller and gave better coverage. More spray may have been used, but it wasn’t anything that substantial.

Collaborator with salad green production and flea beetle problems:
1) Use of insect screening for reducing flea beetle damage on salad greens. The insect screen Econet M has been purchased for this purpose. It would screen out new populations of flea beetles from entering the high tunnel. To control any larvae or adults that may already be in the high tunnel, you have four products to work with- Entrust, Pyganic, Neemix and Diatect V. All but Diatect V could be tried in combinations to enhance the pest control.

2) Use of insect screening for keeping cucumber beetles from cucumbers, with a further goal to keep bacterial wilt from being transmitted. The insect screen Econet M has been purchased for this purpose. Any cucumber beetles that may already be in the high tunnel or slip in could be controlled with Pyganic, Neemix or Diatect V. Pyganic and Neemix could be tried in combinations to enhance the pest control.

3) Use of insect screening used in the open field for reducing flea beetle damage.It would be supported in the field with materials and design similar to high tunnel support. The insect screen Econet M has been purchased for this purpose. It would screen out new populations of flea beetles from entering the area. To control any larvae or adults that may already be in the area, you have four products to work with- Entrust, Pyganic, Neemix and Diatect V. All but Diatect V could be tried in combinations to enhance the pest control. Use of insect screening in the open field was developed to enhance the quality you obtain with salad greens produced subject to full sum and wind, that results in them being more toughened up. Will also desire to move the material frequently and easily.

Result (summary)-
1) Did not get to insect screen but will try next year.

2) Tried Pyganic and Neemix combined and gradually increased rate until the results were noticeable but not adequate. The biggest problem was that it just doesn’t kill the beetles. Customers did accept the product, but they did need to stop with wholesale accounts when damage was bad. Farmer’s Market sales continued. But the control does not give the grower any confidence, especially compared to rotenone. And they had to treat more often. Neemix did not burn the salad greens.

3) Did not use Diatect. Just did not get to it.

Collaborators: