Saturday, July 7, 2012

The Horror: Japanese Beetles in My Garden

My poor raspberry

It has finally happened. After two years of knowing that our garden was tempting fate, the Japanese beetles have finally found us. I know I shouldn't be shocked.

Why? Because I realize that they are incredibly common garden pests in the mid-Atlantic/Northeast region, and I accept that community gardens tend to have more pests than backyard gardens because of the concentration of tempting treats. Somehow up until now we have been untouched; we have had every-other-garden-pest known to man, but we have never had these and I can't help feeling somehow let down by the garden fates. Haven't we suffered enough? 

A little background:

For those of you not familiar, the Japanese beetle or Popillia japonica was *accidentally* introduced to the US in the first part of the 20th century, likely through infected root stocks imported from Japan. It is fairly easily identified because of its iridescent coloring and little white "tufts" along the sides. They are dreaded by gardeners and farmers all over the US due to the widespread damage they cause. In 2008 alone they were estimated  to have caused as much as $450 million in damages to US agriculture, according to the U.S. Department of Agriculture.

Why are they so dreaded? Well, the upshot is that these are not very picky bugs that feed on a whole host of garden goodies. They are crappy fliers but they have good vision and a strong sense of smell which they put to use to seek out new food sources including a crazy-wide variety of flowers and many things in our garden like tomatoes, raspberries, peppers, blackberries. As they feed they skeletonize the plants' leaves which can  irreparably damage the plant. To make matters worse, they use that great sense of smell to find each other. The ladies put out a pheromone that attracts males to same site so they can get it on and make oodles of grubby babies (literally) which go after turf and lawns. Thus they are damaging as babies and as adults.

What do we do? Right now, there isn't much we can do. Traps apparently do not work well, and we found the beetles in our garden to late to interrupt the larval stage. Supposedly the kaolin clay will help and we may try some prophylactic applications of the surround-at-home protectant but whether we can keep it up enough to stem the tide is debatable. I only really only care about damage to my tomatoes, which are unfortunately right near the raspberries.  For now we will have to hope the garden muses are on our side. Maybe this beetle was just stopping by on it's way to our neighbor's grapes?

Additional Reading:

  • On an interesting note I found this cool 2008 Science Daily article describing great strides that an entomology professor at UC Davis has made into research of the beetles' sex pheromones. He has isolated, identified, cloned and express a pheromone-degrading enzyme that could be manipulated to keep males from finding and mating with females, thus interfering with their life cycle. While this doesn't help us right now I'm glad someone is working on the larger issue for American agriculture.  
  • Colorado State University Extension Service Fact Sheet on Japanese Beetle

No comments:

Post a Comment