So this
posting I wanted to talk a little bit about Brown Marmorated Stink Bugs
(BMSB). I have heard so many crazy theories about them during my time in
Virginia, and I’d like to take the time to set the record straight.
First
though, I’ll share a few funny examples of things I've heard about BMSB.
“The
government released the BMSB back in the 90’s to take care of the
overpopulation of lady bugs”
“They were
purposely released by the Chinese government as a form of bio-terrorism”
“Ladybugs and
native stink bugs mated to create the super bug”
OK, those are
pretty funny, especially to a bug geek like me. But let’s get to the
facts.
Here in VA we
have over 13 native species of stink bug, a few of which are very
beneficial in the garden. For example the assassin bug (which I mentioned
in a post last year) is a serious predator in the garden, using those sucking
mouth parts to kill other insects. BMSB or Halyomorpha halys is native to
China, Japan, Taiwan and Korea, and is considered an agricultural pest, though
the populations are not as high as they are here. It was first documented in
the US in 1998 in Allentown PA, but was probably here before that. Most
likely the first individuals were stowaways in shipping containers. (We all
know how they like to squeeze into small spaces) They are now found in at least
35 states though they may not be breeding in all of them. They were first
documented in VA in 2004, and they had invaded the entire state by 2010. In VA
they can have up to three generations per year depending on temperature. When
they emerge from our houses, wood sheds and barns every spring they head out to
the forests and farms. They then feed and mate for about two weeks before
they begin to lay eggs on the underside of leaves. Each female is
responsible for about 400 eggs. They are laid in clusters and take
between 3 and 7 days to emerge. At this point they are in their first
nymphal instar. They will go through 5 of these with about a week in each
stage. All of the nymphal stages are wingless; wings develop after the 5th
instar. When they are adults, and have wings, they become very mobile, moving
easily between crops as some food sources are exhausted and more become
available. There are over 300 different hosts for BMSB, including grapes,
berries, tree fruit, tomatoes, eggplant, beans, and some ornamentals. Their
feeding results in deformation and rotten blemishes rendering the fruit
worthless. I couldn't find any comprehensive information on the agricultural
economic damage these pests have done, but in 2010 farmers reported a loss
between 25 and 40% to apples resulting in a 37 million dollar loss for that
year.
OK, now for
the good news. First: our native predators and parasites are already adapting
to utilize this new food/breeding source. There was a study conducted in OH
that started in 2005. They collected stinkbug eggs from around the state and
found that about 5% had been parasitized by wasps that lay their own egg inside
that of the BMSB. In 2012 they conducted the same study again and found that up
to 29% of the eggs were now parasitized. It has also been shown that
native birds are feeding on these insects much more than they did initially.
Second: there are a lot of people working on this problem from various
different angles, and there is a lot of money being put into it. The US dept.
of AG has classified the BMSB as the top invasive species of interest. The US
department of Ag, the Land Grant Universities, the EPA and the USDA are all
putting money and resources into finding the solution. Several universities are
testing the possibility of releasing the parasitic wasp that is native to Asia
and keeps the population there in check. (Parasitic wasps are nothing to be
afraid of. They are tiny creatures that do not bite or sting humans.)
Unfortunately it was recently stated that it will probably be three years or
more before this is a possibility. There is also a group that is sequencing the
genome for BDSM in the hope that they will find a key to an extremely targeted
pesticide, or a key to their defense mechanisms. There are groups working on
mass trapping projects using the bugs own pheromone as a lure. Most
institutions agree that a biological (as opposed to a chemical) control is the
best way to go. Let’s hope the solution presents itself sooner rather than later.
For more information on the current studies that even you can participate in regarding BMSB please visit www.stopbmsb.org.
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Who knew that chickens love watermelon? |
Now, for the
garden. It has been a pleasant few weeks; Great weather and a lot less rain. We
have been harvesting quite a bit, and planting all of our greens for
fall. We put in kale, chard and mustard. We plant lettuce, spinach
and pac choi weekly. We have also been seeding French radishes and Japanese
salad turnips every other week. All of this work should keep us rolling
in produce well past frost. We removed the shade cloth from the green houses
and the plants seem to like it. The second generation of cucumbers is
coming along really well and started to flower this week. Peppers
eggplant and tomatoes have begun to slow way down, but are still ripening and
doing well. The king lima beans began to flower this week and it looks as
if we should have quite a bumper crop. I checked on the sweet potatoes
yesterday and they are coming along really well. The kitchen is already
starting to experiment with them and yesterday I got to taste a sweet potato
ice cream that was delicious.
Our current
harvest list includes; lettuce, spinach, radishes, summer squash, baby carrots,
beets, tomatoes, eggplant, peppers, haricots verts beans, okra, water melons,
shallots. Edible flowers, herbs and micro greens.