Page 16 - 2017 Griffin Gazette Issue 4
P. 16

By Tami Van Gaal,     sticking or transplant, and continuing at       Now that we understand the need to focus
                             CEA Division          regular intervals until the crop is harvested.  on prevention when using BCAs, we can
                             Leader                Early prevention is especially important        discuss the best options for preventative
                                                   when there is no effective chemical control     use. BCAs are generally not crop specific.
                             Most growers pro-     option available for a crop.                    With a few exceptions, what works great in
                             ducing edible and                                                     lettuce will also work great in tomatoes and
                             medicinal crops uti-  One of the biggest mistakes growers can         medicinal crops. Remember that BCAs
                             lize biological con-  make when utilizing BCAs is to delay the        target insect and mite pests – these tiny
                             trol agents (BCAs)    first release until the pest is present in      warriors do not sting or bite the people
                             as part of their in-  the production space. Waiting becomes           working in the crop.
                             tegrated pest man-    problematic for two reasons. First, delayed
agement plans for a number of reasons.             release risks establishment of the pest         Aphids – Parasitoid wasps are the primary
Top concerns include a desire to reduce            within the crop. Second, delivery of BCAs       preventative tool for aphid control. A blend
chemical pesticide use, a lack of effective        requires a little planning. With the exception  of two species of wasps, Aphidius colemani
and allowed products for a specific crop,          of beneficial nematodes, BCAs can't             and A. ervi, is a perfect choice for prevention,
and a need to slow the development of              be stored in advance of use. And, most          providing protection against a wide variety
resistance within a pest population. The           BCAs need to be ordered by mid-week for         of small and large aphid species. Aphidius
BCA species used will depend on the target         delivery the following week. The risk is that   ships as parasitized aphids, called aphid
pests and the crop production methods.             if one waits until the pest is seen to order    mummies. The adults will emerge after
                                                   BCAs, it’s possible that more than a week       shipping and are simply released into
Think of BCAs as a protective shield over          will pass before the BCAs are delivered. It’s   the crop. Release is particularly easy
the crop. This shield is most effective if         far better to order in advance for known        with A. colemani blister packs. Aphidius
it’s in place before the pests are present.        crop cycles. Some growers place routine         are effective in both greenhouse and
Therefore, the best plans will call for a          orders weeks or months in advance. Talk to      warehouse situations, and are most
focus on prevention over curative control,         your Griffin sales representative to put this   commonly used with lettuce, leafy greens,
achieved by releasing BCAs at sowing,              practice in place for your operation.           herbs, peppers, medicinal marijuana and

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