Friday, January 30, 2009

Alien Invaders, Part I

I like to stop by my state's extension service on occasion to read the news. The news for the last couple of months have been all about alien invasions and how to control them. The first alien invader that we noticed showed up at our house in 2006 around Thanksgiving time. Their little triangular shapes swarmed out of the sky towards the house trying to break in. "Take me to your lights," they wanted to say. Yes they were moths - winter moths.

They coated any surface outside that was white. They beat themselves futilely against the glass at night. They totally covered our white doors, making it an effort to get inside without dragging a dozen with us each time. They were very annoying and we hadn't seen them before. They had probably been around the year before, but not in enough profusion to make us sit up and take notice. Now we do.

What weird moths they are too. They are most prevalent in December. Their biology must be very different to be able to function in the cold. I really wonder what their antifreeze is. Northern New England doesn't get them. It is too cold. We live right on the border of their range. We had some very frigid temperatures in November and December. I'm hoping it killed a lot of them off, because they have become a very big pest to our forests.

In springtime their children munch on the trees. I haven't seen such caterpillar poop rain since the last gypsy moth invasion. It comes in such quantities, I keep thinking of sweeping it off my patio and collecting it for fertilizer for the garden. On Cape Cod the invasion is so bad, the oak trees have started dying. They can only take so many years in a row of getting defoliated in the spring before they start to die (the invasion started in Plymouth in 2003 and has spread).

The one good thing that seems to have come out of it in my yard has been the influx of birds. I have seen more different species of birds in my garden than I ever have before (especially warblers). Those caterpillars make good baby food.

Luckily we have a good weapon against our invader. Our own little dive bombing aerial weapon is a fly. Though maybe it is more like ground troops setting mines. They lay their eggs on the leaves which the caterpillars eat. The parasitic fly grows from the soon to be ex-caterpillar. When Nova Scotia was invaded with the same moth, it took ten years for that control to work. Massachusetts started releasing flies in the area about four years ago, so we have a few more years of heavy infestation to go yet. I hope my trees survive.

Our other invasion is also taking down our trees, but deserves its own post.


  1. Hi Daphne, good grief, winter moths? Who woulda thunk it? The fly sounds diabolical, nature can ge pretty down and dirty sometimes. The stuff of science fiction writers. I hope your trees survive and the birds do their part. Warblers are so wonderful. The thought of raining caterpillar poop, well, not pleasant.

  2. Where did they come from originally? Weird stuff! Kim

  3. Frances, not not very pleasant, but I always wear a hat when going outside (or try to) so I'm protected. The caterpillars themselves when they fall out of the trees on their silk is actually more disgusting, because the hat won't protect you.

    Kim, they originally came from Europe, but they are in balance in Europe as the fly is also a native there.

  4. Sounds just awful. As annoying as flies can be, I hope they do help some...well, a lot! My husband is from Maine and as you said, they don't have them north of you...and I've never heard his family mention them. It's not an infestation to take lightly. I hope your next post isn't really about your trees being wiped out. That's just sad, all the way around.

  5. Daphne, your poor trees- so sorry to hear this. White moths, I've never heard of such a thing. Keep us posted :) on this. Do they at least die down as the weather warms? Or get worse?

  6. Daphne,

    Sorry if this was sent twice- having problems leaving comments on a few blogs today.

    I wanted to tell you, off subject, that I've been reading through your older posts and I gotta say, your soil looks great! Looks like you've worked hard on it. I learn a lot reading your blog.

  7. Jan, well at least not MY trees, but it really is pretty sad.

    DirtDigger, You never see the moths except in the winter. The caterpillars are out in the spring. They cocoon up and stay that way until late November. Thanks for the compliment. I do love my soil and try to treat it well.