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After emulsifiable formulations of aldrin, chlordane, and DDT were each applied to Umapine loam soil at 6 rates ranging from 0.625 to 20 lb per acre, sugarbeets were grown in the treated plots for 3 consecutive years, 1965-1967, and samples of soil and mature sugarbeets were analyzed by gas chromatography. The half-lives of aldrin, aldrin plus its metabolite dieldrin, dieldrin, chlordane, and DDT were 3.1, 8.5, 29.7, 14.3, 22.9 months, respectively. The residues in mature sugarbeets were proportional to the residues in the soil at the time of planting. In 1965, residues of aldrin and dieldrin in beets averaged 18% of the total concentration of the 2 compounds in the soil; in 1966 and 1967, residues that were primarily dieldrin averaged 8.4% of the concentration in soil. Residues of chlordane and DDT in the beets averaged 9.6 and 5.5%, respectively, of the concentration in soil at the time of planting. more...

In laboratory tests, the mortality of sugar-beet wireworms, Limonius californicus (Mannerheim), in soil treated with shortlived insecticides was a function of the product of the concentration of insecticide multiplied by the time of exposure. In the field, Limonius spp. are transients in the upper (treated) layers of soil so the duration of exposure to soil treatments is largely fixed. Thus, the potency of a shortlived treatment in the field is primarily determined by its absolute toxicity and residual concentration. The relative potency of different non-persistent treatments can therefore change considerably with time. Dyfonate® (O -ethyl S-phenyl ethylphosphonodithioate), Bay 37289 (O -ethyl 0-2,4,5-trichlorophenyl ethylphosworms, in potency to the recommended standards, parathion and diazinon. The relative toxicity (based on the LD90 value) was parathion = diazinon = Dyfonate > Bay 37289> carbofuran. The relative persistence was Bay 37289 > Dyfonate > carbofuran = disunion > parathion. Thus, the initial relative potency of treatments with 4.5 kg/hectare of the chemicals was Dyfonate = diazinon = parathion> Bay 37289 = carbofuran, and 6–8 weeks after application the theoretical residual relative potency was Bay 37289 > Dyfonate> diazinon > parathion = carbofuran. more...

Studies of pesticide residues on strawberries were conducted in 1957, 1958, 1959, and 1960. It was demonstrated that the berry caps will contain from 28% to 60% of the residue on harvested strawberries. Studies of seven chlorinated hydrocarbons, nine phosphate insecticides, a carbamate insecticide, and four fungicides showed, with only two exceptions, that sprays applied 24 hours before sampling did not leave residues in excess of established tolerances. Thiodan® (6,7,8,9,10,10-hexachloro-l,5,5a,6,9,9a-hexa-hydro-6-9 methano-2,4,3-benzodioxathiepin-3-oxide) applied 24 hours before harvest left residues in excess of the tolerance of 2.0 p.p.m.; also, demeton in more than two spray applications, the last applied within 14 days of harvest, left residues in excess of the 0.75 p.p.m. tolerance. Variation of the spray pressure from 30 to 200 p.s.i. did not have an appreciable effect on residue deposits. more...

A field of dent corn was treated with a granulated formulation containing 5% of heptachlor, at the recommended time and dosage (1 pound heptachlor per acre), for control of first-brood European corn borers, Pyrausta nubilalis (Hbn.). Corn samples were analyzed for heptachlor and heptachlor epoxide at intervals after insecticide application. Holstein dairy cows were pastured in this field after ear harvest and milk collected from them at regular intervals. Butter was made from this milk. Extracts of butterfat were analyzed colorimetrically for heptachlor epoxide. Because there was no significant difference between the absorbance values of control and test samples, it was concluded that no heptachlor epoxide was secreted in the milk of the test cows. more...

In 2 field tests, 28 lb per acre of 14.3% diazinon granules and 100 lb per acre of 4% Stauffer N-2790 ( O -ethyl S -phenyl ethylphosphonodithioate) granules were broadcast and worked into the soil before planting of sugar beets. Subsequent infestation of the spinach leaf miner, Pegomya hyoscyami (Panzer), were significantly lower in treated than in untreated plots. Sugar beets were grown in similarly treated soil in a Greenhouse where precautions were taken to prevent contamination of foliage. Leaves from 32-day-old seedlings were analyzed chemically by gas chromatographic techniques. Residues of 0.32 ppm of diazinon and 0.048 ppm of Stauffer N-2790 were recovered. Both insecticides had therefore been absorbed and trans located by the plant, thus rendering untreated tissues insecticidal. more...

An analytical procedure for determining residues of Bayer 39007 in plant materials is described. After the residues were partially purified, they were hydrolyzed with methanolic sodium hydroxide and the products of hydrolysis were reacted with the color-forming reagent p -nitrobenzenediazonium fluoborate. Two applications of Bayer 39007 granules at 2.76 kg actual toxicant per hectare per application in 20-cm bands over the tops of small sugar beet plants left 0.43, 0.15, and 0.05 ppm in sugar beet foliage 55, 90, and 117 days after the second application. The treatment was phytotoxic and the plants remained yellow for 6 weeks. Sugar beet roots and crowns had 0.02 ppm Bayer 39007, 117 days after the 2nd application. Potato tubers had 0.18 ppm Bayer 39007 residue 86 days after banding with 10% Bayer 39007 granules at 2.24 kg actual toxicant per hectare. Bayer 39007 did not give satisfactory control of the green peach aphid, Myzus persicae (Sulzer), when used as seed, soil, or foliage treatments all potato or a foliage treatment on sugar beets. more...

Soil fumigation with Telone® (mixed dichloropropenes), DD® Mixture (dichloropropanc-dichloropropene mixture), and ethylene dibromide, applied at 20 gal, 25 gal, and 36 lb/acre, respectively, and broadcast applications of granulated diazinon, parathion, and phorate, applied at 2, 4, and 3 lb/acre respectively, gave economic control of the Pacific Coast wireworm ( Limonius canus LeConte) on potatoes in sandy loam soil. Cullage was reduced 93.6-100%. Granulated disulfoton, broadcast at 3 lb/acre, gave significantly less control than other broadcast treatments. Post-planting sidedressings of granulated parathion, phorate, Stauffer N-2790 ( O -ethyl S-phenyl ethylphosphonodithioate), and Bayer 25141 [ O-O -diethyl O-p -(methylsulrfinyl)phenyl phosphorothioate), applied at 3 lb/acre, reduced cullage 74.4-85.2%. Granulated disulfoton and Bayer 37289 ( O -ethyl 0-2,4,5-trichlorophenyl ethylphosphonothioate) at 3 lb and naphthalene crystals at 450 lb/acre were significantly inferior to the other sidedress treatments. Phorate and disulfoton granules gave as good control when metered onto the soil surface in bands 6 in, wide in the furrow left by the press-wheel potato planter as when side dressed in the soil at the same rate. Of all diazinon, disulfoton, parathion, and phorate treatments, only phorate applied in the planter press-wheel furrow left a detectable residue above the tolerance in tubers collected 3 weeks before harvest. more...