 ello fellow mulch spreaders. The
Goddess is here this week to tell you more about biological pest control
methods. This week's garden heroes are the parasitiod wasps of the family
trichogrammatidae, and especially trichogramma pretiosum Riley, that little
non-stinging wasp that can work wonders when it comes to caterpillar control
in your garden.
 Trichogramma pretiosum are beneficial
insects that really mess up the dinner plans of pest caterpillars and other
lepidopteran critters that can really damage a garden in short order. Corn
ear worm, tomato horn worm, and cabbage loopers all can be controlled in
the garden with less monetary expenditure than it takes to spray, and a
lot less time is used releasing trichogramma into the garden than would
be needed to apply a spray. The most important aspect of releasing trichogramma
into the garden is that after release they continue to work until the targeted
pest is controlled. This is how they work:
- You're out in your garden at dusk (or anytime, for that matter).
- You see a fast-moving moth around your tomatoes or a cute little white butterfly hovering around your prized perennials. They're laying eggs!
- The tiny trichogramma wasp also sees this egg laying and gets ready to go to work.
- The moth or butterfly moves off to another garden to victimize it, or you attack it in mid-flight with a barrage of ninja throwing stars.
- Trichogramma moves in and lays its eggs inside of the eggs of the moth or butterfly by using an ovipositor which she has instead of a stinger.
- Trichogramma goes on her merry way to find some more bad guy eggs to parasitize.
- Trichogramma's egg hatches inside of the host egg and the tiny larval wasp eats all of the host, interrupting the plans of the pest insect before it has a chance to eat in your garden.
Nature is brutal, but very effective.
Trichogramma wasps are probably the most widely released beneficial insect
in the southwestern United States. It is used by smart growers of fruit,
vegetables and ornamentals to control caterpillar and worm pests on their
crops. The real beauty of this method of pest control is that the targeted
pests can not develop a resistance to trichogramma like it could when a
chemical pesticide is used. Trichogramma eats the pests there's no defense
against that. Chemicals are as toxic to you as they are to the pests, and
often ineffective against the targeted pest due to resistance. Instead of
coating the garden with toxic substances, it seems logical to this goddess
to have trichogramma working round the clock. The bad guys don't stand a
chance.
When releasing trichogramma into
your garden, it is good to wait until the first signs of a caterpillar or
worm doing their business. This will ensure that you have a food source
for the wasps when they are released.
Releasing trichogramma is very simple.
When you purchase the insects, they come to you as parasitized moth eggs.
You just hang the little strips on a branch in the vicinity of your caterpillar
problem and forget about it. Trichogramma is on the job!
Adult trichogramma wasps are nectar
and pollen feeders, so it is a good idea to plant nectar-rich flowering
plants like any of the mint family; they really like the flowers of the
dill weed as well. So do some companion plantings of these kinds of plants
for your benefit as well as for trichogramma's well being. This will help
to keep the adults from finding a source of nectar outside your garden,
and I'm sure many of you can find a use or two for fresh mint or dill in
the kitchen. Everybody wins except for the bad guys. I like stories like
that, don't you?
Next week we will be discussing late
summer care for your rose garden and how to get a few extra weeks of bloom
before letting them rest. Come up and see me sometime. | 
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