- 11 



more than clear plexiglas ( = a neutral surface ) indicates that 

 EAS captures on white were the result of positive attraction and 

 not simply random collision. 



Table 1. Comparative captures of EAS adults on rectangles of var- 

 ious colors. 7 replicates. 



Rectangle Total No. EAS adults 



captured 



White 61 



Gray 25 



Clear plexiglas 18 



Yellow 3 



Aluminum foil 1 



Black 1 



Red 1 



Green 



Orange 



Spectrophotometer analysis of light reflected from apple blos- 

 som petals and all other blossom parts (stamen, pistal, etc.) showed 

 all flower parts to be high in reflectance at wavelengths from 400- 

 650 nm, and very low in reflectance in the ultra-violet part of the 

 spectrum (300-400 nm) . The human visible spectrum is 400-700 nm; 

 the insect visible spectrum is 300-650 nm. 



In our second test, we therefore compared 5 types of white 

 rectangles: zinc oxide, Day Glo primer, white enamel, lead oxide, 

 and Zoecon pre-dyed white cardboard. The first three were low in 

 ultra-violet reflectance (as were apple blossoms) and the last two 

 were high in UV reflectance (unlike the blossoms). 



The results (Table 2) showed that zinc white, which most close- 

 ly mimics apple blossoms in color reflectance pattern, captured the 

 most EAS. Day Glo and enamel whites captured nearly as many EAS 

 as the zinc white, but Zoecon and lead white, which were poor mimics 

 of apple blossom reflectance patterns, were not at all attractive 

 to EAS. These results indicate that sticky-coated rectangles coated 

 with either zinc oxide white or Day Glo primer white could be used 

 to monitor EAS activity. 



Table 2. Comparative captures of EAS adults on rectangles of vari- 

 ous white surfaces. 10 replicates. ^__^ 



Rectangl? Total No. EAS adults 



captured 



Zinc white 90 



Day Glo primer 62 



White enamel 49 



Zoecon white 3 



Lead white 



