Wooden Pesticide-Treated Sphere 



Sphere Body: 

 Feeding Stimulant: 



Surface: 



8.4-cm wooden sphere. 



42. 5g sucrose bound with 7.5g paraf- 

 fin. Ingredients are heated to 302°F, 

 granulated, and pressed to form 2" caps 

 with 8 flutes. Sugar is released from 

 the top of the sphere during rainfall. 



Red latex paint containing 2% (a.i.) 

 imidacloprid. 



(b) 



Sugar/Flour Pesticide-Treated Sphere 



Sphere Body: 7.7-cm sphere, consisting of the follow- 

 ing: 38g water, 90g sugar, 83g corn 

 syrup, 158g com Hour, 3.7g Cayenne 

 pepper, 0.4g sorbic acid. 



Feeding Stimulant: 



Surface: 



173g sucrose and fructose bound in 

 sphere body. Sugar is released from the 

 body of the sphere during rainfall. 



Red latex paint containing 2% (a.i.) 

 imidacloprid. 



Figure 1. Schematic illustrations of PTS used in 2000: (a) wooden PTS bearing a sugar/wax cap, and (b) sugar/ 

 flour PTS. 



captured on interior unbailed monitoring traps (four traps on 

 central trees of each plot) and percent injury to fmit in samples 

 taken five times from July to September. 



In addition to measurements of whole-plot treatment 

 effectiveness, we assessed the structural durability of each 

 PTS type bi-weekly from June to September. For these as- 

 sessments, we recorded the percentage of spheres impacted 

 by the two most commonly damaging influences: feeding on 



caps or spheres by rodents and mold growth on sphere sur- 

 faces. For each of four sample sites, we also recorded the 

 amount of rainfall accumulated during each sample period 

 as a factor potentially leading to premature breakdown of 

 sphere effectiveness (tlirough wash-off of sugar and/or toxi- 

 cant). 



At the mid-point (6 weeks of field exposure) and end 

 (12 weeks of field exposure) of the trial, we retrieved indi- 



46 



Fruit Notes. Volume 65, 2000 



