7 articles tagged "Beneficial Insects and Mites".

Over the past several weeks, there have been a number of reports of high populations of aphids on cucurbits, as well as report of disappointing levels of control with various insecticides. Without getting into the specifics of individual complaints, here are some suggestions for improved control of aphids. Remember that our primary method of control of aphids is natural enemies. There are a wide variety of predators and parasites than usually keep aphids at reasonable levels. Usually, an outbreak of aphids is an indication that a grower has done something to kill off the natural enemies, which allows aphid populations to reproduce unchecked. And, aphids have a very high reproductive capacity, so without those natural enemies they can build up in number very quickly. Obviously, there are other pests that cucurbit growers need to control, so some disruption of the natural enemies is to be expected. However, growers should only[Read More…]


Figure 1. A ladybug feeding on aphids

Supplementing the natural enemy population to control insect pests, i.e. augmentation biological control, is of interest to many high tunnel producers. Augmentation biological control has proven very effective at managing a number of greenhouse pests and there are a variety of commercial suppliers. For high tunnels, the greatest challenge is keeping the released predators or parasitoids inside the tunnels and choosing agents that are effective under high temperatures, during the peak of the growing season. We have evaluated some of the more common control agents in high tunnel cucumber and tomato production. The convergent ladybug, Hippodamia convergens, is not grown in a growth facility but rather caught in the wild in the western U.S. (typically California) and shipped throughout the US for control of aphids in particular. They are a fairly inexpensive predator (1500 for about $15.00), the immature form (larvae) and adults feed on aphids (Figure 1). However, you[Read More…]


Figure 1. Aphids on tomatoes in a high tunnel (Photo credit Wenjing Guan)

We have begun to receive the first reports of aphid outbreaks in high tunnels on tomato, pepper, and cucumber (Figure 1). Aphids are a very common problem in high tunnels because the covering excludes rainfall, which is a major mortality factor for small insects like aphids. Some growers are interested in using biological control in their high tunnels because the ability to contain natural enemies within the tunnels increases the likelihood of achieving control. Based on our experience, we believe that lacewing larvae hold the greatest promise for successful biological control of aphids in high tunnels. Because they don’t fly, they are less likely to leave the high tunnel than many other biological control agents. There are a number of biological control suppliers who can provide lacewing larvae for growers. For growers interested in chemical control, some of the insecticides that could be expected to provide good control and are[Read More…]


​Indiana is working on a state pollinator protection plan, which is being spearheaded by the Office of the Indiana State Chemist with input from various stakeholders, including growers, farm chemical company representatives and beekeepers. A large part of the plan will involve protecting bees from pesticides. This plan is part of a national movement initiated by the president last year. A “national strategy to promote the health of honey bees and other pollinators” was released on May 19 by the newly established Pollinator Health Task Force. The national plan offers an assessment of the decline of honey bees, wild bees and monarch butterflies. The decline in honey bees coincided with the introduction of parasitic mites but other factors including pesticides play a role. Last year the nation lost 40% of its hives. Beekeepers had to scramble to make new hives to pollinate the nation’s crops. The annual loss has been[Read More…]


​During the past two weeks, I am aware of two beehives that were almost decimated when insecticides were used nearby.  In both cases, the commercial applicators had used the DriftWatch program before spraying to look for sensitive crops or bees near the targeted crop.  However, neither hive was recorded in DriftWatch.  DriftWatch is a web-based program to help growers of sensitive crops and bees to map their location.  Pesticide applicators can bring up maps of the area to be sprayed, warning them of potential issues. DriftWatch is free of charge.  Sign up at https://in.driftwatch.org/map.  Growers and beekeepers provide information such as name, address, phone number, and the location of the field or hive.  You do not need to have an email address to sign up for DriftWatch.  Simply call Beth Carter at the Office of the Indiana State Chemist, (765) 494-1585, to get an account set up.  If you do not have a computer at home,[Read More…]


​As you all know, many of our vegetable crops are dependent upon pollinators to move pollen from flower to flower. The cucurbits, muskmelons, cucumbers, watermelons, pumpkins, and squash, are completely dependent on insect pollination. Eggplant, okra, lima beans, and peppers will set fruit without pollinators but can have increased yield if pollinators are present. Honey bees are likely the most important pollinators for most of these crops, but other pollinators such as a number of species of native bees and other insects can also provide useful pollination services. In recent years, there has been a lot of attention given to larger than normal die off of honey bee colonies, commonly referred to as colony collapse disorder. There has been a great deal of discussion in the scientific community and in the public about the cause or causes of these colony deaths. Some of the suspected causes include new disease organisms,[Read More…]


Driftwatch registry map with pin marking high tunnels at Pinney-Purdue Ag Center circled in yellow as an example.

​Vegetable, fruit, and organic farmers can register their production areas on Driftwatch.org to let commercial pesticide applicators know where the fields are. Beekeepers can also register sites where beehives are located. Once sites are registered and approved they appear on the Driftwatch registry map (see Fig. 1) and partnering applicators are notified. This helps applicators reduce drift or accidental application to vegetable crops.  Registration is free and easy. Why not do it today? Visit Fieldwatch.com to find the user guide with instructions.  If you registered fields last year you will need to renew the sites in order for them to show up in the registry this year. When renewing, it isn’t necessary to reenter all the information, just what has changed for 2015. Instructions for renewal are also online.


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