Partial budget analysis was used to evaluate soil treatment alternatives to methyl bromide (MeBr) based on their cost-effectiveness in the production of strawberries (Fragaria ×ananassa). The analysis was conducted for two geographical areas: the piedmont and coastal plain area (including North Carolina and Georgia) and the mountain area of western North Carolina, based on 7 years of field test data. The fumigation alternatives evaluated were Telone-C35 (1,3-dichloropropene 61.1% + chloropicrin 34.7%), Telone II (1,3-dichloropropene 94%), chloropicrin (Chlor-o-pic 99% and TriClor EC), InLine (1,3-dichloropropene 60.8% + chloropicrin 33.3%), and metam sodium (Vapam or Sectagon 42, 42% sodium methyldithiocarbamate). The MeBr formulation was 67% MeBr and 33% chloropicrin (Terr-O-Gas) with the exception of the earlier trials where a 98:2 ratio was used. In the piedmont and coastal plain area, the soil treated with chloropicrin showed the best results with an additional return of $1670/acre relative to MeBr, followed by Telone-C35 with an additional return of $277/acre. The projected return associated with shank-applied metam sodium was approximately equal to the estimated return a grower would receive when applying MeBr. Fumigating with drip-applied metam sodium, InLine, and Telone II as well as the nonfumigated soil treatment resulted in projected losses of $2182, $2233, $4179, and $6450 per acre, respectively, relative to MeBr. In the mountain area, all of the alternatives resulted in a projected increase in net returns relative to MeBr. The largest projected increase was $1320/acre for the InLine treatment, while the added returns for the TriClor and Telone-C35 applications were estimated to be $509 and $339 per acre, respectively. The drip-applied metam sodium application resulted in an additional return of $40/acre, and the added revenue for the nonfumigated soil treatment was $24/acre more than MeBr treatment. Although technical issues currently associated with some of the alternatives may persist, results indicate that there are economically feasible fumigation alternatives to MeBr in the production of strawberries in the southeastern U.S.
Geologic Map of the Santa Barbara Coastal Plain Area, Santa Barbara County, California
