Editor’s note: Kelly R. Jackson takes questions called into his phone recently at the Christian County Extension Office and answers them in the Garden Corner column.
Question. What’s the best way to get rid of a yellowjacket nest?
Answer. Yellowjacket nests are often underground in old animal burrows or beneath rocks or landscape timbers. They also build nests in walls, attics, crawlspaces, and behind exterior siding of buildings. If the nest can be located, it often can be eliminated by applying an aerosol-type wasp and hornet spray into the opening. Insecticide dust formulations containing Sevin, DeltaDust, or Drione, are especially effective but require a hand duster to dispense several puffs of the dust into the nest opening. Insecticide dust blown into the opening penetrates farther than sprays, and the workers transport it throughout the nest.
Ideally, treatment should be performed at night, when most of the yellowjackets are in the nest and less active. Pinpoint the nest opening during the daytime, so you will remember where to direct your treatment after dark. Approach the nest slowly and do not shine the beam of your flashlight directly into the nest entrance as this may startle the wasps and cause them to fly toward the light. Instead, cast the beam to the side to illuminate the nest indirectly. If possible, place the light on the ground rather than in your hand.
When contemplating extermination of a yellowjacket or hornet nest, be fully aware that you are entering a danger zone. There is no pest-control scenario more frightening than a “blown” wasp or hornet treatment. It is often prudent to hire a professional, especially when access to the nest requires a ladder or is difficult. If the nest is located away from frequently used areas, another option is to wait and do nothing. In Kentucky, yellowjacket colonies die off naturally after the weather turns cold.
Q. Why do earthworms come to the surface after a rain?
A. Although the common thought was that earthworms surface after a rain because their tunnels are flooded and they need to breathe; new research from soil experts agree they are surfacing for migration purposes.
Wet conditions after a rain gives earthworms a better opportunity to travel greater distances across the soil surface than they could through the soil, according to Dr. Chris Lowe, lecturer in Waste and Environmental Management, University of Central Lancashire in Preston, United Kingdom. He also stated that earthworms can survive several days fully submerged in water and to be able to breath, they actually require moisture in the soil.
Another explanation involves rain-drop vibrations on the soil surface sounding similar to predator vibrations, like that of moles. Earthworms often come to the surface to escape moles.
“Rain can set up vibrations on top of the soil like mole vibrations,” said Professor Josef Gorres of the University of Vermont’s Department of Plant and Soil Science. “Similar to how earthworms move upwards and out of the way when predator vibrations are felt, they could move in a similar way for rain vibrations.”
Kelly R. Jackson is the Christian County Extension Agent for horticulture. He can be reached at 270-886-6328 or visit Christian County Horticulture online at www.christiancountyextension.com.