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The Pherocon Ic trap captured the greatest number of Cydia caryana (Fitch) adult males and all trap designs appeared to represent population trends equally well. Pooled data from all trap height experiments indicate that traps placed 9.14 m above the orchard floor captured significantly more adult males than those placed at 4.57 m height. Horizontal placement of traps within the tree canopy indicated a significantly greater capture in the central portion of the canopy than at other locations. Correlations between the total capture of male adults and the rate of fruit infestation were not significant.

Emergence of hickory shuckworm, Cydia caryana (Fitch), adults from larval overwintering sites was bimodal. The major emergence peak occurred during the period of mid-March to mid-May and the smaller activity period during July and August. Pheromone trapping was effective for monitoring population trends during generations 1 and 5 of C. caryana but less so during generations 2, 3, and 4. Activity patterns suggest the species is crepuscular rather than truly nocturnal.

Surveys of the populations and the parasitoids of Liriomyza sativae Blanchard on late-season tomatoes were conducted during two years in two locations of Alabama. Population trends and extent of parasitism were tabulated. Ten species of hymenopterous parasitoids from 4 families were reared from field-collected larvae. The three most prevalent parasitoids and their percent occurrence were: 1) Opius dimidiatus (Ashmead) (Braconidae), 33.3%; 2) Chrysonotomyia sp. (Eulophidae), 20.8%; and 3) Halticoptera sp. (Pteromalidae), 19.5%.

Granular systemic insecticides were tested for effectiveness In controlling Fiorinia theae Green on container-grown Camellias under greenhouse conditions. Heavily infested Plants were treated once each spring at rates equivalent to 8-64 pounds AI per acre per six-inch depth. Outstanding Control was obtained with aldicarb and DS-15647 (3.3-dimethyl-1-methylthio-2-butanone O -(methylcarbamoyl)oxime). Excellent control also was provided by dimethoate and carbofuran at high rates. Phorate provided effective control only at the highest rate tested. Disulfoton was ineffective. Increased insecticidal effectiveness was Obtained when treatments were applied during periods of Active plant growth. Visual evaluation of the colonization of new foliage by tea scale was found to be satisfactory for preliminary screening of candidate insecticides.

To determine the effect of Empoasca fabae (Harris) on alfalfa yields, adults collected in the field were used to infest alfalfa growing under cages but otherwise under normal field conditions. Populations of 30, 60, 120, and 240 per square foot on alfalfa 2.5 inches tall reduced yields by 45, 57, 79, and 95%, respectively, whereas on alfalfa 8 inches tall the same populations reduced yields by only 3, 16, 34, and 47%. Where populations of 30 or 60 leafhoppers per square foot were caged on plants of different heights, it was found that yield reduction declined with delayed infestation. In both cases the yield reduction per leafhopper, which ranged from 1.5 to 2.0% down to 0.1% or less, is more nearly geometric than arithmetic.

Insecticides were screened for effectiveness against insect defoliators of collards under field conditions in Alabama. Tests were conducted for 3 years during different periods of the growing season, and the insect complex varied in population sizes and species composition. Good control of imported cabbageworm, Pieris rapae (L.), and diamondback moth larvae, Plutella xylostella (L.), was obtained with Galecron® ( N' -(4-ehloro-o-tolyl)- N, N -dimet-hylformamidine), methomyl, Monitor® ( O , S-dimethyl phosphoramidothioate), and Dipel® (preparation of the HD-1 strain of Bacillus thuringiensis Berliner var. kurstaki de Barjac and Lemille). Satisfactory control of high populations of cabbage looper, Trichoplusia ni (Hubner), was obtained with Dipel at 0.5 and 1.0 lb/acre, Galecron at 1.0 lb/acre, and Orthene® ( O , S-dimethyl N -acetyl phosphoramidothioate) at 0.75 lb/acre.

The potato leafhopper, Empoasca fabae (Harris), was reared over a 3-year period both in temperature-controlled cabinets and under known field conditions. In the laboratory, the relation between temperature and rate of development appeared to be linear at temperatures between 60° and 83°F; above 88° the rate of development decreased, and its maximum occurred probably at 86°. The base temperature for the species was approximately 52.5°. A thermal constant of 435 degree-days was established. Under field conditions, the computed thermal constant varied in magnitude, depending on the location of the recording instrument and the method of determining the mean daily temperature. Even when the official temperatures of a weather station situated 5–15 miles away from the fields were considered, the resulting thermal constant was fairly consistent over the 3-year period. On the basis of these results, if the peak oviposition date is known and if the official daily temperatures of a nearby weather station are used, the peak adult emergence of the developing leafhoppers can be expected when 480–500 degree-days (over a base of 52.5°F) have accumulated.

In laboratory rearing studies and 2 types of field studies, Empoasca fabae (Harris) oviposition rates ranged between 2.5 and 3.8 eggs per female per day, and the average number of eggs per female ranged between 33.7 and 57.4. In 9 separate studies conducted in the laboratory over a period of 13 months the percent females produced ranged from 47.7 to 56.3 and averaged 52.8. In 10 cage studies under field conditions conducted over a period of 3 years, the percent females in the progeny ranged from 48 to 52 and averaged 50.2. Likewise, over a period of 4 years, in sweep-net collections of breeding populations of E. fabae in alfalfa, the sex ratios were consistently close to 1:1.

The test was conducted on Chandler Mountain, St. Clair County, AL. Seedlings were planted (1 plant/1.5 ft) Jun 20. Each plot consisted of one row, 20 ft long with 10 ft distance between rows. A randomized complete block design with 4 replications per treatment was used. Treatments were applied weekly from Aug 17 to Sep 13 using hand operated compressed air sprayers delivering 50 gal/acre. Manzate 200 was added to each spray at 2.0 lb ai/acre. Damage data were taken on Sep 18. Fruitworm damage was determined by examining 100 fruits per plot. Treatment efficacy on leafminer was evaluated by collecting from each plot all the mined leaves that could be gathered by one person within 5 minutes and then counting the number of mines (both active and inactive).

Seed pieces were planted on March 2. Prior to planting, the field was treated with Mocap at 6 lb ai/acre. During early growth, the plants were sprayed with the fungicide Difolatan 4F (using 1.5 quarts/acre) on May 3, 10, and 17. A randomized complete block design, with 4 reps per treatment, was used. Plot size was 1/200 acres (3 44-inch rows, each 20 ft long) with the plots separated by 5 ft alleys. Experimental sprays were applied using hand sprayers delivering 50 gal/acre. Treatments were made on May 20 and 27, June 4 and 10. Final observations were made on June 17. Potatoes were harvested on June 23 and yield data were taken from the middle rows. Midway through the test period, most Colorado potato beetle larvae went into pupation; as a result, some of the early differences among treatments disappeared. Infestations were not uniform throughout the field. Two replications remained practically uninfested by the European corn borer.

Several fruits, Irish potato tubers, and sweet potatoes were tested as possible hosts for rearing tea scale, Fiorinia theae Green (Homoptera: Diaspididae) in the laboratory. Tea scale developed on all hosts tested but survival was highest on butternut squash. The technique developed for rearing tea scale on butternut squash was used successfully in rearing twelve broods of this insect.

Tea scale, Fiorinia theae Green, has long been a destruetive pest of camellias in the Southeast (English and Turnipseed 1950, Kuitert and Dekle 1972) and homeowners have difficulties in Controlling infestations. Tea scale has no known parasites and no research has been conducted on its predators. A survey of tea scale control recommendations in the southeastern United States revealed that chemical Control by foliar sprays is advocated. Dimethoate soil drenches and disulfoton granular applications also are recommended. Trunk applications of systemic insecticides were tested and gave promising results (Tippins 1969).

The test was conducted in a grower’s field near Atmore, Ala. Corn was planted 24 Mar in 30-inch rows. Test plots were 2 rows wide and 320 ft long, were replicated 4 times in a randomized complete block design. Five insecticides were applied as granules in 7-inch bands over the rows and lightly incorporated into the soil during planting. Diazinon plots were planted with ‘Pioneer 3389’; all other plots with ‘Pioneer 3320.’ The field was irrigated 9 times during the season with 1.5 inches water/application. Stand counts and counts of damaged plants were taken 20 Apr. Plots were harvested 24 Aug, yield data were collected, and the moisture content was measured. Yields were adjusted to 15.5% moisture for comparison.

This test was conducted at the North Alabama Horticulture Substation, Cullman. Tomato transplants were set on Jun 13. Plots consisted of 3 rows, 25 ft long (88-inch centers), with 5-ft alleys. A randomized complete block design with 4 replications per treatment was used. Sprays were initiated when fruit began to set. All applications were made with a Super Blue Boy 6000 high clearance sprayer. Treatments were applied on Aug 5, 12, 26, Sep 2, 9 and 27. For disease control, Manzate 200 (at 1.6 lb ai/acre) was applied early in the season and Difolafan (at 1.0 lb ai/acre) was used late in the season. Tomatoes were harvested 5 times (Aug 25, Sep 1, 8, 16 and 23). Damage and yield data were taken from the middle row of each plot. All fruits were examined visually, and dissected when necessary, to determine damage by the fruitworm.

Tomatoes ‘Homestead 24’ were planted on May 2. Each plot was 1/100 A and included 10 tomato hills. There were three replications per treatment in a randomized complete block design. During early growth, the plants were dusted with Sevin (1.0 lb/A) on May 13, and sprayed with parathion (0.5 lb/A) on May 20 to prevent flea beetle and aphid damage. Applications of test insecticides were made on June 2, 9, 16, 23, and 30. Materials were applied using hand sprayers and plants were sprayed to runoff. The fungicide Bravo (1.0 lb/A) and Biofilm spreader-sticker (6 fl oz/A) were added to each spray mix. Tomatoes were harvested first on July 10 and the number of tomatoes damaged by the fruitworm determined. The plants received an additional spray on July 10, after the first harvest. A second harvest and determination of damage were made on July 22.