58 



tree surface, thus maintaining them within the confines of the cubic 

 foot. 



Tie wire was twisted around the screen to secure it. A clip-type 

 clothespin was placed just beyond the screen and outside of the cubic 

 unit to identify the particular cube. Yellow ribbon was also attached 

 to make locating the cubes easier. 



Three of the cubes were randomly chosen to have one snail, three 



with three snails, and three without any as controls. As the snails 



p 

 were placed on the units, yellow Day-glow numbers representing the 



particular cube unit were applied to the dorsal surface of the shells 

 as in Chapter I, Section 2. A similar number was placed on the clothes- 

 pin for identification. For the first twelve hours (8:00 p.m. until 



8:00 a.m.) the snails were observed hourly. An ultraviolet light, 



p 

 model ULV-56, was used to see the Day-glow painted snail and identify 



it. Temperature, relative humidity, and periods of snail movement were 

 recorded every 15 minutes. 



Pretreatment and posttreatment counts on citrus rust mite popula- 

 tions, as well as presence or absence of sooty mold, were collected just 

 prior to snail infestation, using a modified hand lens (Allen, 1976). 



Ten leaves from nine different cubic feet of citrus were randomly chosen 



2 

 and one 1 cm observation made on each leaf. Numbers of rust mite 



P_. olievora were counted as were positive or negative presence of sooty 



mold. These observations were continued for six days. 



Determination of snail hours each day was initially made by visual 



observations and relative humidity readings. Later, snail hours were 



determined by recorded humidity readings on a recording hygrothermograph 



located near the test tree. 



