USE OF METHYL BROMIDE AND OTHER CHEMICAL PEST CONTROL BY STRAWBERRY AND FRESH TOMATO GROWERS Van Johnson1 U.S. production of methyl bromide is currently restricted to the level produced in 1991. On January 1, 2001, production and importation of methyl bromide in the United States will be prohibited. Methyl bromide inventories could be used up within a few years following the ban. Other industrialized countries will phase out production of methyl bromide, with a total ban by the year 2010 (7). For developing nations, there will be a freeze on production in 2002 based upon an average of the years 1995-1998. These agreements are being revisited in September 1997 at the Ninth Meeting of the Parties to the Montreal Protocol, an international treaty developed to protect the earth from the detrimental effects of ozone depletion. About 60 million pounds of methyl bromide are used annually in U.S. agriculture, primarily for soil fumigation (87%), for commodity and quarantine treatment (8%), and for structural fumigation (5%) (7). Crops, which use methyl bromide as a soil fumigant, include almonds, apples, apricots, cherries, citrus, grapes, nectarines, peaches, plums/prunes, walnuts, carrots, cucumbers, eggplants, fresh tomatoes, melons, peppers, strawberries, sweet potatoes, tobacco, ornamentals, and forest seedlings (6). Strawberries and fresh tomatoes account for about 13-14 million pounds of methyl bromide used annually. California is the number one strawberry producing state and Florida the number one fresh tomato producing state. Sales of strawberries averaged $553 million during 1993-95, and sales of Florida fresh tomatoes averaged $216 million (5). About 90 percent of California's strawberry acreage and Florida's fresh tomato acreage are fumigated with methyl bromide. The primary fumigant alternatives, or combination of alternatives, likely to replace methyl bromide on both strawberries and fresh tomatoes include 1,3-D (Telone), metam sodium, and chloropicrin (including a herbicide on tomatoes). Based on field testing to date, these alternatives are considered by some researchers to be "generally equally effective" as methyl bromide (1,3). The two potential alternatives are currently about 10 percent higher in cost of materials and can be applied using essentially the same equipment as with methyl bromide. As heavy users of methyl bromide, without a history of viable fumigant alternatives, strawberry growers in California and fresh tomato growers in Florida are especially vulnerable to the methyl bromide phaseout. The reasons that use of 1,3-D and metam sodium have been limited to date include the State-related restrictions pertaining to acreage treated, application method, and soil type. For example, 1,3-D use from 1990 to 1994 was prohibited in California. There are new ____________ 1Van Johnson is an environmental statistician with National Agricultural and Statistical Service, USDA. Walter Ferguson, an agricultural economist with Economic Research Service, USDA, assisted in summarizing data. 31-1 safety precautions that could be taken using these two alternatives, combined with less restrictionson use, that could potentially allow them to replace methyl bromide (1,2,3). However, there are still unanswered questions about the risks associated with the new safety precautions and the lessened restrictions in use that are being considered. Given the lack of history of viable chemical alternatives and the close proximity of the 2001 deadline, the chemical industry is faced with responding quickly to shifting demand conditions for alternatives to methyl bromide. Shortages of fumigant alternatives could result in lower quality or quantity of yield. Lower quality could lower prices growers receive for their crop. Reduced yields could increase prices at the retail level. In the longer term, domestic markets and the balance of trade could be adversely affected by increased imports. Chemical Use for California Strawberries and Florida Fresh Tomatoes (4) • During the 1992, 1994, and 1996 survey years, California strawberry growers reported an average of 4.4 million pounds of methyl bromide on 89 percent of the 23,967 acres grown. Growers reported a stable use of methyl bromide with a three-year range of 85 to 92 percent of the 23,300 to 25,200 planted acres treated using 4.0 to 4.9 million pounds of active ingredients (Table 1). • During the 1992-96 survey years, strawberry growers, in the seven major-producing states (CA, FL, NY, NC, OR, WA, WI), reported an average of 5.7 million pounds of methyl bromide on 61 percent of the 44,550 acres grown. The only other fumigant reported was chloropicrin. • In 1996, California strawberry growers reported 2.1 million pounds of chloropicrin applied on 87 percent of the acres planted. Other pesticides, applied during the growing season, included herbicides (2,4-D, DCPA, Glyphosate, napropamide, paraquat, sethoxydim, simazine, terbacil), insecticides (abamectin, azinphos-methyl, Bt, carbaryl, carbofuran, chlorpyrifos, diazinon, dicofol, endosulfan, fenbutatin-oxide, fenpropathrin, malathion, methomyl, naled, oxydemeton-methyl, potassium salts, propargite), fungicides (benomyl, captan, copper hydroxide, fosetyl-al, iprodione, metalaxyl, myclobutanil, sulfur, thiophanate-methyl, thiram, vinclozolin), and other chemical: metaldehyde. (Table 2). • During 1992-1996, Florida fresh tomato growers reported an average of 7.2 million pounds of methyl bromide on 94 percent of the 45,767 acres grown. Compared with the 1992 and 1994 survey years, the growers in 1996 reported about 3 million fewer pounds used, which was due to less acreage planted and a lower rate per acre than reported in previous years. • During 1992-96, fresh tomato growers in the six major-producing states surveyed (CA, FL, GA, NJ, NC, TX), reported an average of 7.8 million pounds of methyl bromide on 47 percent of the 99,233 acres grown. Chloropicrin was the only other fumigant reported. 31-2 • In 1996, Florida fresh tomato growers reported 1.8 million pounds of chloropicrin applied on 79 percent of the acres planted. Other pesticides, applied during the growing season, included herbicides (metribuzin, paraquat), insecticides (abamectin, Bt, endosulfan, esfenvalerate, imidacloprid, methamidophos, methomyl, permethrin) and fungicides (benomyl, chlorothalonil, copper hydroxide, mancozeb, metalaxyl) (Table 3). References 1. Patterson, David. Personal Communication, Project Leader, Methyl Bromide Florida Demonstration Project, Florida, ARS, U.S. Department of Agriculture, September 8, 1997. 2. Thomas, William. Personal Communication, U.S. Environmental Protection Agency, September 5, 1997. 3. Trout, Thomas. Personal Communication, Project Leader, Methyl Bromide California Demonstration Project, California, ARS, U.S. Department of Agriculture, September 5, 1997. 4. U.S. Department of Agriculture. Agricultural Chemical Usage, Vegetables, 1992, 1994, and 1996 Summary, NASS, ERS. 5. U.S. Department of Agriculture. Agricultural Statistics, 1995-96, NASS, 1997. 6. U.S. Department of Agriculture. The Biologic and Economic Assessment of Methyl Bromide, National Agricultural Pesticide Impact Assessment Program, July 1992. 7. World Wide Web Home Page: http://www.epa.gov/docs/onone/mbr/mbrqa.html. 31-3 Table 1. Methyl bromide: Strawberries, California and Fresh Tomatoes, Florida Survey Acres Area Rate per Total year planted applied crop year applied Pounds Million Percent per acre lbs. Strawberries, California 1992 23,400 85 203 4.0 1994 23,300 91 212 4.5 1996 25,200 92 211 4.9 Average 23,967 89 209 4.4 Strawberries, 7 States 1/ 1992 46,300 53 201 5.0 1994 45,800 61 207 5.8 1996 44,550 68 207 6.3 Average 45,550 61 205 5.7 Fresh tomatoes, Florida 2/ 1992 49,400 93 172 7.9 1994 47,900 94 183 8.2 1996 40,000 94 143 5.4 Average 45,767 94 166 7.2 Fresh market tomatoes, 6 States 1992 105,100 46 168 8.4 1994 103,900 48 179 8.9 1996 88,700 50 138 6.1 Average 99,233 48 162 7.8 1/ Survey states included CA, FL, NY, NC, OR, WA, and WI. 2/ Survey states included CA, FL, GA, NJ, NC, and TX. Sources: 1. Agricultural Chemical Use, Vegetables, 1992 Summary, USDA, NASS, ERS, Ag Ch 1(93), June 1993 2. Agricultural Chemical Use, Vegetables, 1994 Summary, USDA, NASS, ERS, Ag Ch 1(95), July 1995 3. Agricultural Chemical Use, Vegetables, 1996 Summary, USDA, NASS, ERS, Ag Ch 1(97), July 1997 Table 2. Strawberries: Agricultural Chemical Application, California, 1996 1/ Agricultural Area Rate per Total chemical applied crop year applied Pounds 1,000 Percent per acre lbs. Herbicides: Napropamide 6 2.01 3.1 Insecticides: Abamectin 67 0.05 0.8 Bt 42 2/ 2/ Carbaryl 16 2.98 12.0 Chlorpyrifos 15 1.40 5.4 Dicofol 13 1.65 5.6 Fenbutatin-oxide 19 1.55 7.3 Fenpropathrin 11 1.28 0.8 Malathion 35 9.28 81.4 Methomyl 30 1.58 12.1 Naled 21 2.09 11.3 Potassium salts 7 9.41 16.0 Propargite 12 1.11 3.3 Fungicides: Benomyl 27 1.05 7.1 Captan 77 12.63 244.0 Iprodione 50 2.50 31.5 Myclobutanil 63 0.29 4.6 Sulfur 65 13.12 214.3 Thiram 48 8.61 104.8 Vinclozolin 39 2.19 21.4 Other Chemicals: Chloropicrin 87 95.60 2,102.5 Metaldehyde 8 1.64 3.5 Methyl bromide 92 210.66 4,858.5 1/In 1996, 25,200 acres of strawberries were planted in California. 2/Rates and total applied are not available because amount of active ingredients are not comparable between products. Source: Agricultural Chemical Usage, Vegetables, 1996 Summary, NASS, ERS, Washington, DC, Ag Ch 1(97). 31-4 Table 3. Tomatoes, Fresh: Agricultural Chemical Application, Florida, 1996 1/ Agricultural Area Rate per Total Chemical applied crop year applied Pounds 1,000 Percent per acre lbs. Herbicides: Metribuzin 62 0.57 14.1 Paraquat 66 0.87 22.9 Insecticides: Abamectin 74 0.02 0.6 Bt 88 2/ 2/ Endosulfan 44 1.93 34.2 Esfenvalerate 22 0.14 1.2 Imidacloprid 70 0.39 11.1 Methamidophos 47 2.96 55.8 Methomyl 55 1.27 28.2 Permethrin 57 0.45 10.2 Fungicides: Benomyl 48 0.79 15.1 Chlorothalonil 95 8.34 317.6 Copper hydroxide 96 7.44 285.1 Mancozeb 93 10.22 379.3 Metalaxyl 35 0.17 2.3 Other Chemicals: Chloropicrin 79 58.55 1,842.1 Methyl bromide 94 142.52 5,345.7 1/ In 1996, 40,000 acres of tomatoes were planted in Florida for the fresh market. 2/ Rates and total applied are not available because amount of active ingredients are not comparable between products. Source: Agricultural Chemical Usage, Vegetables, 1996 Summary, NASS, ERS, Washington, DC, Ag Ch 1(97). 31-5