Japanese Beetles
Japanese Beetles are serious pests, attracted to dozens of different plants, including many in the garden. Originally from Japan (where they are controlled by natural predators), Japanese Beetles were first detected in the United States around 1916 and are suspected of entering the U.S. through a shipment of iris bulbs.
Japanese Beetles arrived in our area of Tennessee about 7 years ago. They increased in numbers for several years, but have been decreasing and having less affect for about the last three years. Compared to other years, in 2014 they arrived about 2-3 weeks later in the month of June than usual, and in much smaller numbers. Still it only takes a few to cause some serious damage.
In the image right, the beetles are feasting on corn silks. They also consume the corn tassels at the top, which produce the pollen necessary to pollinate the silks. Each silk represents one kernel on an ear of corn. If the beetles chews off the silks before pollination has taken place, the corn kernel will not develop.
When I spot an infested ear, after removing all of the beetles, I pull back the shucks a bit to expose the remaining silks in hope that the silks might still have a chance to be pollinated.
So far (over the last few years), my corn has filled out and developed properly, even after an attack. It is quite possible the silks were already fertilized before the beetle attack.
When the beetles first made their presence known, my wife and I and our neighbors used traps that attract the beetles with a pheromone scent. The beetles would then fall into a bag below. The second year of their appearance here, my wife and I filled a 30 gallon drum with dead beetles.
However we found, and it has been proven through university studies, that the use of pheromone traps actually attracts more beetles to your vicinity. Many of those drawn by the pheromones will never enter the trap, but they will consume nearby plants and increase the amount of damage you receive.
Be Forewarned: If you do intend to use beetle traps, place them as far away as possible from the plants you are trying to protect.
If beetle numbers are small to moderate,I have found you can control them by picking the beetles off by hand. This best done in the cool early morning when the beetles are moving slow.
When disturbed from their state of rest, the beetle's instinct is to fall, tumbling down into the plant leaves below as they attempt to disappear in the foliage. You can use this to your advantage by placing a cup half filled with water under them.
Simply nudge the leaf or the beetle and they will drop directly into your cup. By only filling the cup half way, the beetles cannot crawl out. Swimming about in the water, they are also unable to take off and fly away.
Leave the container out in the sun and return the next morning, empty and begin your collection again.
However if you wait until the heat of the day to collect your beetles, their first instinct is to fly away rather than drop down into your water container.
Japanese Beetles spend their larvae stage underground. During this phase, the grubs are susceptible to a bacterium called "milky spore." Milky Spore can be purchased commercially in powder form and applied to the soil as a means of prevention.
Thanks as always for your time and attention! Douglas@thefarmcommunity.com |
