The miracle of chemistry
Jul. 26th, 2008 04:19 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
altivoAmazing. The Japanese beetle, Popillia japonica, is a serious pest in North America (for those who didn't know about it.) It's a large, handsome looking beetle that is native to east Asia and Japan, where it has natural enemies that keep its population stable and controlled. Once introduced to America, though, it ran wild. Few native species care to eat the beetle, though I've heard rumors that raccoons will dig up the larvae from under lawns and eat them (eewww, no accounting for raccoons' taste, but I knew that.)
Anyway, last week I noticed a large population of these pests on some wild grapevines near the vegetable garden. They eat leaves, leaving only the skeleton of veins behind, so the damage they do is quite apparent. I started looking around, and sure enough, they have attacked our blueberry bushes and some of the apple trees. They are noted for their resistance to pesticides, but I don't use chemical pesticides anyway. The larvae (and thus the adult beetles) can be exterminated from an area over a period of several years by applications of a bacteria spore to the soil. Like BT on most moths and butterflies, this bacteria causes the larval stage to die, but takes years to establish itself well in the soil. Gary went somewhere and came home with a couple of Japanese beetle traps instead.
I checked and found that some garden experts say the traps are ineffective. They catch only a small percentage of the adult beetles, supposedly, while attracting many more to the area. However, today I observed that the beetles are still there and I want to give my squash and tomatoes a chance to live. So I went and got one of the traps and read the rather vague directions for setting it up.
It consists of four vertical plastic vanes at right angles to one another, with an hourglass shaped plastic bag that hangs beneath them. A sticky pad containing fruit and floral fragrances and some kind of sex attractant is attached to one of the vanes just at the bottom. The scent draws the beetles in and they crash into the vanes, falling into the plastic bag and presumably not being able to find their way out before they suffocate or dessicate or something.
I peeled the cover off the scent pads and affixed them to the trap, which was already hung on a post about ten feet from the infested grapevines but on the far side of their trellis from the garden itself. This just happened to be upwind of the beetles I had noticed.
I had to duck out of there in a hurry. It was like being mobbed by a swarm of bees. I had no idea there were so many Japanese beetles in the area. They are about the size of bees, so you can hear them flying and see them quite easily, especially when there are hundreds about. They are clumsy fliers and apparently when drunk on sex pheromones, they don't look where they are going. Sure enough, they fly right into the yellow plastic vanes and fall into the plastic bag below. I could see the bottom of the hourglass shape starting to swell even as I watched. Standing back and watching the sky, I could see the flight pattern, just as I'm used to seeing bees fly. That little postage stamp sized patch was drawing bugs in from at least half an acre away. I think I'll have to go out in a short while and tie that bag shut at the hourglass waist. A second bag was included with the trap, and I figure any that I seal into the bag and throw into the trash will at least not escape. Anyone want half a pound of Japanese beetles? No? Speak up before they're all gone...
Anyway, last week I noticed a large population of these pests on some wild grapevines near the vegetable garden. They eat leaves, leaving only the skeleton of veins behind, so the damage they do is quite apparent. I started looking around, and sure enough, they have attacked our blueberry bushes and some of the apple trees. They are noted for their resistance to pesticides, but I don't use chemical pesticides anyway. The larvae (and thus the adult beetles) can be exterminated from an area over a period of several years by applications of a bacteria spore to the soil. Like BT on most moths and butterflies, this bacteria causes the larval stage to die, but takes years to establish itself well in the soil. Gary went somewhere and came home with a couple of Japanese beetle traps instead.
I checked and found that some garden experts say the traps are ineffective. They catch only a small percentage of the adult beetles, supposedly, while attracting many more to the area. However, today I observed that the beetles are still there and I want to give my squash and tomatoes a chance to live. So I went and got one of the traps and read the rather vague directions for setting it up.
It consists of four vertical plastic vanes at right angles to one another, with an hourglass shaped plastic bag that hangs beneath them. A sticky pad containing fruit and floral fragrances and some kind of sex attractant is attached to one of the vanes just at the bottom. The scent draws the beetles in and they crash into the vanes, falling into the plastic bag and presumably not being able to find their way out before they suffocate or dessicate or something.
I peeled the cover off the scent pads and affixed them to the trap, which was already hung on a post about ten feet from the infested grapevines but on the far side of their trellis from the garden itself. This just happened to be upwind of the beetles I had noticed.
I had to duck out of there in a hurry. It was like being mobbed by a swarm of bees. I had no idea there were so many Japanese beetles in the area. They are about the size of bees, so you can hear them flying and see them quite easily, especially when there are hundreds about. They are clumsy fliers and apparently when drunk on sex pheromones, they don't look where they are going. Sure enough, they fly right into the yellow plastic vanes and fall into the plastic bag below. I could see the bottom of the hourglass shape starting to swell even as I watched. Standing back and watching the sky, I could see the flight pattern, just as I'm used to seeing bees fly. That little postage stamp sized patch was drawing bugs in from at least half an acre away. I think I'll have to go out in a short while and tie that bag shut at the hourglass waist. A second bag was included with the trap, and I figure any that I seal into the bag and throw into the trash will at least not escape. Anyone want half a pound of Japanese beetles? No? Speak up before they're all gone...
