There seems little doubt that the most important fire ant pest, S. invicta, traveled from South America to Mobile, Alabama, in ship ballast between 1930 and 1940. It spread in all directions from there, limited only by cold winters or desert drought conditions. S. richteri may have arrived earlier (perhaps in 1919), only to be largely displaced by S. invicta. The latter is currently established in 11 states (Florida, Georgia, Alabama, Mississippi, Louisiana, Texas, North Carolina, South Carolina, Arkansas, Tennessee, Oklahoma) and Puerto Rico. A new infestation was discovered in California in 1998, and eradication efforts are under way.
It was predicted that imported fire ants could not survive a winter when the minimum temperature was below -12°C. However, infestations now occurring in southern Oklahoma and Tennessee have led to a revised estimate of -18°C. Another limiting factor is rainfall. The deserts of west Texas have proven a barrier to the fire ant's progression westward. It is likely that annual rainfall of less than 25 cm precludes S. invicta from becoming established unless there is also irrigation.
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Make money with honey How to be a Beekeeper. Beekeeping can be a fascinating hobby or you can turn it into a lucrative business. The choice is yours. You need to know some basics to help you get started. The equipment needed to be a beekeeper. Where can you find the equipment you need? The best location for the hives. You can't just put bees in any spot. What needs to be considered when picking the location for your bees?