USING OUR INSECT PALS TO BATTLE INSECT PESTS

Last Friday Doug and I got a ton of technical advice and hands-on experience about FARMING WITH BENEFICIAL INSECTS;  CONSERVATION BIOLOGICAL CONTROL when we participated in the inaugural Xerces Society  short course by the same name.

BeneficialInsects_coverWe came home with a copy of their very helpful book, Farming with Native Beneficial Insects,, a fat folder of information, 12 pages of typed notes and just a mild case of sunburn.

The class was led by Thelma Heidel-Baker, IPM Specialist, and Sarah Foltz Jordan, Pollinator Conservation Specialist, both with the Xerces Society for Invertebrate Conservation.banner4

This is a great organization.  It’s like the Audubon Society, but for Invertebrates.  For 40 years they have been working to protect endangered species without backbones, which most of us never think about – spineless animals on whom we are more dependent than we can imagine.

WHY FARM WITH BENEFICIAL INSECTS?

We are surrounded by insects.  There are more species of beetles alone than there are plant species in the world.  The beetle species outnumber mammals by almost 100-to-1!  Most insects are harmless.  Some are friendly.  Some are pests, primarily because they have managed to invade habitats beyond their native neighborhoods, often with the unwitting help of humans.

“The greatest single factor in preventing insects from overwhelming the rest of the world is the internecine warfare which they carry out among themselves.”  These words were penned by Dr. Robert Metcalf, a visionary entomologist who spoke out in the 50s as the U.S. was first being blanketed with insecticides.

Big Agriculture did not listen to Metcalf, and instead is waging an ongoing war against pest species, using poisons instead of beneficial invertebrate allies.

This is the way NOT to encourage beneficial insects.

This is the way NOT to encourage beneficial insects.

WHO IS WINNING THE PESTICIDE WAR AGAINST INSECT PESTS?

Right now, this farming season, Big Ag is saturating the world in unprecedented amounts of insecticide.  In the words of Vandana Shiva this approach is war spread thinly over the earth. Many fear this war  will unintentionally decimate our failing honey bee population – collateral damage  that may only be the tip of the iceberg.

The estimated economic value of pest control using wild, beneficial insects is $4.5-12 billion annually for U.S. crops and $100 billion worldwide.  That’s a lot of value from insects that are free for the encouraging.

And that’s a lot of value to be putting at risk with modern agricultural practices that veer toward throwing the beneficial-insect baby out with the insect-pest bathwater.

This class was information rich.  We soaked it up.

This class was information rich. We soaked it up.

Providing our native benficial-insect army with some natural habitat is key, and yet 9+ million acres of grassland/prairie has been converted to cropland since 2008. That’s the largest conversion of habitat-to-cropland since the years just before the Dust Bowl – not a comforting correlation

A huge amount of that conversion to more ag acreage involves fields where every last square foot of ground that used to be native, natural-habitat (such as fencerows and hedgerows) is now under pesticide-drenched cultivation.

A NEW, MORE POSITIVE, STRATEGY THAT JUST MIGHT WORK

Xerces’ findings are that we should be going in the other direction and adding more margin area for native, beneficial insects to survive.  And if we do, they will make their way into our gardens and croplands and put a big dent in the number of the pest insects — reducing or eliminating the need to use poison.

That’s what this class was all about — learning how to identify beneficial insects and how to encourage them.

Doug and two classmates getting hands-on experience at the Ag Station.

Doug and two classmates getting hands-on experience at the Ag Station.

Insect predators like ground beetles, lady beetles, assassin bugs and syrphid flies will consume the baddies.  I have a lot to learn just identifying these guys!

  • Syrphid or hover flies feed on pollen and nectar as adults, but a single larva will eat hundreds of aphids
  • a week.
  • A single Lady Beetle may consume 5,000 aphids in their lifetime.  Fireflies (which are actually beetles) prey on slugs, snails and caterpillars.
  • Minute Pirate Bugs prey on thrips, mites, scale, aphids and small caterpillars.
  • Parasitoid Wasps are among the most abundant beneficial insects on earth, though they are so small that they are difficult to see.

The list goes on and on!

Using info from this short course, Doug and I are developing a plan for the 2 acres of south-facing slope we are in the process of converting from scrubby shrubs and brome grass to a mixed planting of hazelnuts, and possibly elderberries and juneberries.  We plan on making half of our new field a haven for beneficial insects from the start.

The workshop gave us several ideas for designing and restoring habitat – Perhaps the key ingredient in our ag-venture:

  • Field Borders planted to make beneficial insects at home.
  • Pollinator/Insectary Strips – A great way to get services in area where you need them.
  • A beetle bank strip in the middle of things, because these crawling beneficials can’t be effective if the pests they could eat are out of their limited reach.
  • Cover crops that you don’t cut till after they flower.
  • Flowering hedgerows.
IMG_5941

This bumble bee was loving the pollinator-friendly strip at the ag station.

After lunch, we carpooled from our indoor classroom at the UW-Arboretum to an outdoor classroom at the UW West Agricultural Research Station where we got to try our hand at assessing habitat and identifying some of our little friends and foes.

Bumble bees are easy enough to spot, and were all over the single (way too small!) pollinator-friendly strip planted at the Station.  But a lot of the vast army are very tiny and are easier to find sweeping an insect net or even tapping a branch over a piece of white paper.

I photographed and ID'ed this is a long-legged fly.  Adult flies consume thrips, aphids, a variety of other small insects and, of course, spider mites (which by the way, are not insects, but belong to the spider family).

I photographed and ID’ed this is a long-legged fly. Adult flies consume thrips, aphids, a variety of other small insects and, of course, spider mites (which by the way, are not insects, but belong to the spider family).

It’s good to have a 10X lens in your hand when you go out to ID insects so you can appreciate this largely unseen and under appreciated army out there.  And placing the hand lens in front of your phone camera lens can lield some surprising detaied documentation of what you find.

There is going to be another short course on Conservation Biological Control at the NRCS FARMINGTON FIELD OFFICE, Farmington, Minnesota on Tuesday July 28th, 2015 from 9:00 am – 4:00 pm CT.  Click here for details including the agenda.

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2 replies

  1. That sounds really useful. I was so pleased to see the ladybirds (lady bugs?) out earlier than the black fly this year, so hopefully they are ahead of the game. The only problem is this year we seemed to be inundated with the kinds of beetles that seem intent on eating my flowers and leaves of plants. I have seen lots of large metallic looking beetles before but never all congregated on my lupins and munching their way through them. Since we want to plant sweet lupins for feed next year, this is not something we want to encourage. It does tend to feel like we get one pest sorted and another springs up, I sometimes sympathise with the farmers when they resort to chemicals – it can seem such a simpler solution, although as you rightly point out, it is not the long term solution at all.

    • Hi Joanna,
      Yes, sprays seem very direct and straight forward. But I’m committed to trying to find alternatives. And I have the luxury of turning to my local farmers market if I lose a crop.

      Doug and I decided not to grow grapes because in our moist climate there is simply no alternative to straying for certain molds. No organic alternative has been discovered.

      My goal is to find the things I can grow without too much swimming upstream against the local conditions. I don’t want to go to war against the insects. I know they will win in the end.

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