A story broadcast on San Diego’s CBS8 channel recently covered an issue that was causing locals to call their area pest control services. The problem: ant invasions. People in San Diego County have been seeing more and more invasions into their homes this summer and according to a news release published by the Standford News Service, the school released a study that found there was a strong relationship between the weather and infestation.
In order to find the link between the two occurrences, Deborah M. Gordon, an associate professor of biological sciences, led a team of Stanford researchers, who surveyed 69 homes in the Silicon Valley area of California between 1998 and 1999. Once a week, participants of the study were asked to monitor and report an estimated number of how many ants invaded their home. They also were asked to report whether they had used any pesticides to get rid of the ants.
Simultaneously, Gordon and her team members documented weekly temperature and rainfall data at weather stations in the area to compare to the reports from participants of the study.
While some of the products reduced the number of ants, none effectively prevented invasions. Sprays got rid of the most ants, followed by household cleaners and baits, and herbal and natural products were the least effective.
“Our goal was to determine if there really is an association between ant invasions and weather,” Gordon stated in the release. “And if so, does pesticide use affect the intensity of infestation?”
The reports from the study showed that a number of products were used in an attempt to rid the homes of ants including:
• “Cleansers, such as bleach, ammonia, soap, Windex and Formula 409;
• Herbal and natural products, including hot pepper, chili oil, lemon and vinegar;
• Sprays, such as Raid, Black Flag and Hot Shot;
• Baits and traps, including Combat, Grant’s and Ortho Ant Kill.”
Ultimately, ants will likely invade homes during cold and wet conditions, usually during winter months. The study found a smaller peak occurs in hot and dry conditions, around August and September.
“When you don’t have ants in your house, putting out pesticides won’t make any difference,” Gordon stated. “The most reliable cause of a decline in infestation may be a change in the weather. They come in because of the weather, and they go out because of the weather.”
What should you do if you have ants?
Sigma Pest Control staff are trained to help manage ants and similar pests. Keeping ants out of homes and buildings is an ongoing process, not a one-time treatment. That’s why we recommend Sigma’s Quarterly Pest Control Service (QPCS) as the best solution for ant prevention and infestation.