Orchard, applicator

Diazinon SOW was applied by air blast sprayers in accordance with typical application practices for orchards. Application began in March and continued until early-to mid-July. Dormant sprays typically contained diazinon in an oil mixture. Aqueous emulsions were applied as foliar sprays thereafter. Eqmpment was calibrated to provide an application rate of 3.4 kg active ingredient (a.i.)ha At least five applications were made at approximately 2-week intervals. During these applications, 233 samples were taken from spray tanks across the four treatment fields to estimate the application rate in PA, and 244 samples were collected in WA. 

With reference to the surface deposits accruing from orchard application of insecticides, certain characteristics which enhance their value as implements in the chemical control of many species of insects—physical persistency and chemical stability—may also be conducive to the contamination of the harvested fruits with potentially deleterious residues. 

Dermal Route. In orchard applications the dermal route of exposure has been established as the major one (2, 3). Durham... 

Table III. Applicator Exposure During Airblast Spraying of Chlorinated Hydrocarbon Insecticides in Orchards Application Rate 1-3 lb Al/acre...

Use of higher plants has attracted attention for the remediation of TCE-contaminated aquatic systems, and in particular the use of hybrid poplar (Newman et al. 1999). Although this was encouraged by the removal of labeled TCE to >90% using hybrid poplar under hydroponic conditions (Orchard et al. 2000), and the ability of hybrid poplar to metabolize TCE (Newman et al. 1997 Shang et al. 2001), there are additional considerations that must be evaluated to determine its general applicability. 

Figure 1 Mean diazinon dissipation from vegetation collected within two orchards in Pennsylvania following five applications spanning Julian days 93-187. Note that leaves were infrequently present until Julian day 120...

Table 1 Diazinon concentrations in crop samples collected from European starlings (Sturnus vulgarus) following several applications to orchards in eastern Washington, USA...

Collection stations were located at various distances from the point of application up to 2600 ft in the aerial studies, 1300 ft in the ground application studies and 1000-1500 ft in the orchard studies. 

The amount of parathion spray residue on soft fruits is roughly proportional to the length of time between date of application and date of analysis. Parathion spray residue was lost from the surface of Delicious apples at the rate of 80 to 85% in 12 to 13 days and 93 to 100% in 30 to 32 days. The rate of loss was the same for 1-pound as for 4-pound concentrations. Fifty-five samples, collected from commercial orchards, were analyzed. No significant relationship was found between the number of days between spraying and analysis and the parathion residue. There was no significant difference in parathion residue due to the concentration of the spray mixture used. All residues were only a fraction of 1 p.p.m. 

Bifenthrin Orchard 2 app at either 20, 30, or 50 g a.i./ha with 21 day spray interval Effects reported on all groups of predators at all application rates but with more marked effect at 50 g a.i./ha Full recovery not reported at 50 g a.i./ha by end of study. Signs of recovery were reported by end of study at 20-30 g a.i./ha... 

However, climate, season, and cropping system specificity still represent serious limits for a further diffusion of soil solarization practice, as effective results are mostly provided by summer application to specific cropping systems, i.e., greenhouse and field horticulture and fruit orchards, in warm climates. Adversely, solarization is less effective and more expensive in cooler regions and not suitable for rain-fed agronomic crops in large areas. 

Tjamos EC, Biris DA, Paplomatas EJ (1991) Recovery of olive trees with Verticillium wilt after individual application of soil solarization in established olive orchards. Plant Dis 75 557-562... 

Pheromones are used primarily for monitoring pest populations, but their use as pest suppression tools has also been proposed. These alternative uses include mass trapping, mating disruption, and lure and kill. Although these approaches have been tried with varying levels of success in field and orchard crop systems, they have had limited application for the management of stored-product insects. 

---