Fumigation with Chloropicrin, Metham Sodium, and EPTC as Replacements for Methyl Bromide in Southern Pine Nurseries

Abstract

Abstract The effects of soil fumigation with chloropicrin alone or in combination with metham sodium and or with EPTC on the growth of loblolly pine (Pinus taeda L.) seedlings and on nutsedge (Cyperus spp.) control were investigated at three forest tree nurseries. Fumigation with chloropicrin plus metham sodium (CMS) significantly increased seedling numbers and growth compared to controls. Averaged among nurseries, mean root-collar-diameter increased from 0.14 to 0.17 in., and biomass from 0.14 to 0.20 lb/ft2. This produced seven more plantable seedlings and 6.5 more grade 1 seedlings/ft2 in CMS compared to not fumigated plots. Fumigation increased average potential sales $7,100/ac and increased present values, projected for the growth increases for additional grade 1 seedlings, by $25,900/ac. Fumigation increased biomass per unit area similarly at tested bed densities (10 to 29/ft2), but at low bed densities (≤20/ft2) the present values associated with grade 1 seedlings increased more than at higher densities. South. J. Appl. For. 24(3):135-139.