The computer simulation showed an automatic aeration controller could keep insect populations below economically damaging levels without insecticides, even as far south as Oklahoma. Scientists say the automated system could be set to turn on fans whenever air temperature is 18 degrees F lower than grain temperature. The automated system suppresses insects by cooling the grain as soon as possible, and saves electricity and grain weight loss by cooling only when necessary. Tall whitetop, also called perennial pepperweed, is an increasing problem in western native hay meadows. The weed is among the five worst noxious weeds in Nevada.
Cattle there rely on native grass hay for winter feed.
But they won't eat hay dominated by this weed. Several chemicals kill its flowering stalks and leaves, but range managers don't have a tool for killing its roots or slowing their spread. In the first two years of an ARS study, chlorsulfuron controlled the roots. Scientists suspect tall whitetop is spreading rapidly across the West, though its full extent is unknown. In one part of their study, ARS scientists monitored the weed's spread in 500 acres of privately owned grassland.