Weed Population Dynamics after Summer Solarization

Soil solarization, a non-chemical method of soil pest control, has been used to manage insects, nematodes, and weeds in agricultural systems. This study focused on optimizing the duration of solarization for weed management in northern Florida by examining weed coverage, density, and biomass, and comparing solarization effects on several summer weeds. In the summer of 2003, solarization plots were installed for durations of 2, 4, and 6 weeks, concluding on 12 Aug. After treatment, weed coverage and density were monitored every 2 weeks. All durations of solarization reduced weed coverage compared to non-solarized plots throughout the experiment. Weed densities were 200 times lower in solarized than non-solarized plots at 14 days post-treatment. Even at the conclusion of the experiment (56 days post treatment), population counts were lower in solarized plots; there was no difference in weed density among solarization durations; and there was a 90% reduction in total weed biomass in solarized treatments when compared to nonsolarized treatments. Indigofera hirsutaand Cyperus rotundus, the two dominant species, responded better to 4- and 6-week solarization treatments than to the 2-week treatment.