While some nature lovers among us may declare that Japanese beetles are a part of nature and should be permitted to chomp away at the greenery, I don’t find myself among that set. For one thing, if we want to extend that line of thinking, then clearly humans are a part of nature too; should humans be allowed to do whatever they want on the grounds that they are “natural?” For another thing, Japanese beetles are an introduced species in the United States, not part of the original ecosystem: they’ve been in this country for less than a century and aren’t being very well restrained. They certainly haven’t been that well restrained in my yard, taking the leaves on a newly planted Mountain Ash tree to pieces:
Some say that these “bug bags” actually attract more Japanese beetles than they trap. My experience, with two traps each placed about 40 feet away from the victimized tree in question, is that the traps work. The picture you see on the left is typical of the condition of the Mountain Ash tree before I introduced a Japanese beetle bug trap scented with pheromones and colored an attractive yellow; the picture you see on the right is representative of the current condition of the Mountain Ash, two weeks after I put a pair of “bug bags” up. The difference in the leaf condition is striking, with new growth being given a chance to leaf out before being chewed down. Before I hung the traps up, I’d find 6-8 beetles on my young tree every morning. By the morning after the traps went up, the Japanese beetles stopped coming to the tree and started falling in the bag. I haven’t spotted a single beetle on that tree since.
The Japanese beetle traps I’ve deployed don’t use pesticides that could harm other living things; they attract with a pheromone scent and physically trap Japanese beetles in a slick bag out of which they can’t climb. They seem to me like the perfect pest management tool in terms of effectiveness and environmental responsibility. Yes, they seem that way, which is why the cynic in me wonders whether there is some dastardly downside to these devices that I haven’t considered. Is there a reason I shouldn’t be hanging these bags in my yard?