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Carnation cuttings, set through 6X8 wire mesh in raised 3 ft wide beds of Leon sand ammended with peat, were grown under 25% natural saran shade cloth similar to commercial production. Plants were set and losses reset the first week of February. Weekly treatments by M-45 fungicide was applied for disease control. Populations of spidermites were allowed to develop until March 27 when acaricides were applied with a compressed air hand sprayer. Plots consisted of 36 plants or 12 sq ft of bed; each treatment was replicated 6 times. Samples consisted of 5 leaves/plot taken from the lower portions of the plant. Mites and eggs were counted under 10 x magnification on March 29, April 12, 24 and May 9. Five flowers were pulled from stems in each plot, placed in plastic bags, and mites extracted by shaking the flower heads in warm detergent water.

Laboratory and field tests established that the adult tomato pinworm, Keiferia lycopersicella (Walsingham), is crepuscular (evening) in its mating habits. Approximately 75% of males captured in traps baited with female pheromone extracts and placed in tomato fields in February were caught during the twilight period (5-8 PM EST). Females exposed to an abrupt-transition photoperiod in the laboratory exhibited maximum calling activity 0.5 after lights-out, but males were responsive to female extracts throughout the night. Virgin pairs mated only during hours 1-3 of the laboratory scotophase. Females called most and males were most responsive to the pheromone in a laboratory olfactometer during the third night after eclosion. Males were more responsive when bioassayed with dim light both above and below the olfactometer than when there was light only from below.

Experiments were conducted on a commercial vegetable and ornamental transplant range in Sun City, FL during the 1977 fall and winter to determine attraction of various trap colors and to monitor leafminer dispersal into the range. Significantly more adult flies were captured on yellow traps than on yellow-green, orange, green and blue. Use of a protective transparent plastic bag on the yellow poster board traps had no significant affect on the number of adult flies trapped. Significantly more flies were trapped on cards located on the periphery of the range nearest the prevailing wind and within 100 ft of commercial tomato farms. Fly movement onto the transplant production range and infestation within production houses reflected both proximity of source and prevailing wind direction.

Phytoseiulus macropilis (Banks) was studied in the laboratory to determine its potential rate of population increase when fed on eggs of Tetranychus urticae Koch. The shortest developmental period was 4.7 days for males, and 5.8 days for females reared at 27 + 2?C and 90% + 5% RH under 12L:12D. Mean generation duration was 14.2 days with an average reproductive rate of 1.89 eggs per female per day. Predation of P. macropilis, expressed as the number of prey eggs consumed per individual, was 5.9 eggs for the immature stages and 194.1 eggs for the adult or 7.9 eggs consumed per adult per day. Mean adult longevity was 25.3 days. For each predator egg produced, 4.3 prey eggs were consumed. The intrinsic rate of predator population increase (r1,) was calculated as 0.27 individuals per female per day.

Seven foliar applied insecticides were evaluated for their effects on hemispherical scale on Ardisia. Four replications of each insecticide were applied with a hand sprayer to ca 10 inch high potted greenhouse grown plants infested with all stages of scales. Counts of live scale nymphs were made on two leaves per plant before treatment and at 7 and 14 days after treatment.

Seed heads of `DeKalb E-57' sorghum, planted on 26 April, 16 May, and 1 June 1976, were harvested in the soft dough stage and placed in emergence cages to determine the temporal pattern of emergence for the sorghum midge, Contarinia sorghicola (Coquillet), and its parasite, Aprostocetus diplosidis Crawford. Midge emergence began at the end of the milky stage, peaked 5-6 days later, and was complete in 10-11 days. Parasite emergence began 7-8 days after the end of the milky stage, peaked at 12-14 days, and was completed in 18-19 days. The emergence of the 2 insects overlapped from the 7th to 11th day after the end of the soft dough stage, Toxic residues of insecticides, applied to kill emerging adult midges, could be present for 7 days after the end of the soft dough without harming the adult parasites.

Three acaricides were tested for their effect on the twospotted spider mite population infesting neanthe bella palms in 3 in.pots in a greenhouse. Sprays were applied by handspraying until foliage was thoroughly wet. Five replicates were treated with each material and compared to an untreated check. Counts of eggs and mites were made on a 1 cm square of an infested leaflet. These counts were made before treatment and 1, 7, and 14 days after treatment.

Seasonal populations of the fall armyworm, Spodoptera frugiperda (J. E. Smith) and the velvetbean caterpillar, Anticarsia gemmatalis Hubner were surveyed during 1975-77 at Gainesville, Sanford, Bradenton, and Homestead, Florida. S. frugiperda was most abundant at Homestead during the spring and fall, and tended to be more numerous at the other locations during the summer and fall. A. gemmatalis larvae were present on soybeans at Homestead during all except 3 months of the study; populations peaked in the fall at all 4 sites.

Foliage mealybugs Phenacoccussolani group infesting purple passion plants were treated with five insecticides and numbers compared to those of untreated plants before and three, seven and 14 days after treatment. Counts were made on three leaves and the two internodal regions between them from each of five, one plant replicates. Insecticides were applied to foliage with a hand sprayer to the point of runoff. Plants were grown in containers under greenhouse conditions.

The population of beet armyworms, Spodoptera exigua (Hubner), in a chrysanthemum range near Ft. Myers, Florida, was simulated by a model based on the insect life history, the maximum and minimum temperatures, and light trap records. The increase in population with no treatments was similar to that observed at Red Rock, Arizona, and at Gainesville, Florida. Then the effect of insecticides on the life stages was superimposed in the model. With treatments, the populations could not be sustained at the original level. However, when migrant adults were added, the original populations were approximated. Thus, eggs from migrant moths place an unceasing demand upon the control program to insure plant protection and to maintain production.