But the ants come back after a few weeks. We need a longer solution. The growth regulators and other new chemicals work by inhibiting egg laying or stopping young ants from maturing when foraging ants deliver the chemical-laced baits to the colony. The keys are finding a bait that is more attractive than natural foods in the orchard and determining the best time to place the bait in the orchard. This summer, farm advisors in Fresno, Kern, Merced and San Joaquin counties will test baits based on cornmeal and some of their own formulations.
Ant diets vary by species and time of year.
Using a newly acquired farm implement, Mitchell plants tomatoes this spring into the residue of rye and vetch grown over the winter at the UC West Side Research and Extension Center near Five Points. The system has proved to be extremely effective in Eastern and Southern states, where summer rains can wash away unprotected sandy top soils. In those areas, the cover crop mulch also inhibits weeds, provides nutrients, cools roots and adds organic matter to the soil. Whether the benefits will outweigh the cost in California remains to be seen.