As temperatures drop, more and more Texas residents can expect to have unwanted winter guests drop in for a visit as well, according to a Texas AgriLife Extension Service entomologist.
"This time of year, primarily outdoor insects such as roaches, spiders, centipedes and scorpions will try to wriggle their way into people's homes in search for warmth and water," said Molly Keck, integrated pest management specialist for AgriLife Extension in Bexar County.
Keck suggested that Texas residents take precautions to "winterize" their homes against insects and small animals.
"Start by sealing up any exterior holes or cracks," she said. "You can use caulk to seal up solid walls like stucco or steel wool to fill weep holes in brick to keep insects and small rodents out and still allow continued airflow."
Keck also suggested trimming tree branches to keep them from touching a home's exterior walls or roof, as well as removing any debris or wood, trash or compost piles near the home.
"Tree branches can allow access (to points) of entry for insects or possibly something larger," she said. "And wood piles, piles of debris or compost heaps and bins can make a warm shelter for insects. The closer they are to the house, the greater the chance of bugs getting indoors."
However, Keck said, finding roaches in a compost bin or pile is not necessarily a bad thing.
The two most common types of roaches found in compost bins are the American cockroach and wood cockroach, Keck said, and they help break down composting material.
"During the winter, people may see more cockroaches in their compost bins because it's nice and warm in there," she said. "But so long as you keep the bin sufficiently far from the house and the house sufficiently sealed, there's probably no need to treat for them."
Treating cockroaches in a compost pile or bin might inadvertently kill other beneficial insects as well, reducing the efficiency of the composting process, she said.
"Another thing to remember is that even though it's winter, it's still very dry, and bugs will try to get in to find water as well as warmth," Keck said. "There's not much you can do about that, but remember that any standing water near your home will draw bugs closer."
Another pest that tends to show up in people's homes during wintertime is the fungus gnat, she added.
"Fungus gnats feed in the fungus that grows in the soil of potted plants, and that fungus is usually there as a result of overwatering," she said. "When people bring their plants inside to protect them from a freeze, they often notice lots of these gnats flying around the garage or interior of their home. That's partly because the warmth speeds up their life cycle."
Keck said the best way to control the gnats is to repot plants in fresh soil prior to bringing them inside.
"However, once adult gnats are in the home they can be treated using an aerosol pesticide spray, provided it is applied in accordance with label instructions," she said. "The adults only have a life cycle of about a week, but you still have to eliminate the fungus to ensure there are no eggs left to produce more gnats."
Another area of "winterizing" for pests is the home garden, Keck noted.
"People with gardens should completely remove dead plant material in the winter so the same pests don't return in the spring," she said. "Cucumber beetles, caterpillars, stinkbugs and other non-beneficial pests that may have bugged them in the past year will be back next year if they don't remove the material that contains their eggs or provides shelter for dormant adults."
Keck said even though many insects are in or nearing a state of diapause or dormancy, others are still creeping and crawling around, frantically searching for a warmer, wetter place to winter.
"And if you live in a more rural area, it's probably still a good idea to give your shoes or boots a good shaking to be sure there are no scorpions in there before you put them on," she said.
Information and descriptions of insect biology and behavior of typical Texas insects can be found at http://insects.tamu.edu/fieldguide/index.html .
More information can also be found at Keck's blog, http://bexarento.blogspot.com.