108 
Psyche 
[Vol. 94 
threads). Parallel threads representing radii were spaced 6 mm apart 
and perpendicular to these other threads (woven parallel 1-2 mm 
apart). The threads of each AS W were covered with equal amounts of 
adhesive (Stick’em Special TM Sea Bright Enterprises) the night 
before they were placed in the field. The traps were transported to and 
from the field in reinforced cardboard boxes with dividers to keep 
webs from touching one another. 
In the field, frames were suspended on sturdy string with centers at 
1 .50 m high in microhabitats similar to these exploited by M. gracilis. 
Traps were placed in the field seven times, on nonrainy days between 
23 July 1980 and 14 September 1980 (four times in Mt. Airy Forest 
and three times in Felter’s Tanglewood). They were in place by 0730 
hrs (while spiders were actually building their webs) and removed by 
1900 hours (when spiders began taking down their webs). Care was 
taken in moving throughout the study sites so as not to destroy the 
vegetation of the microhabitats; two study sites were chosen in order 
to keep this problem to a minimum Temperature and humidity were 
recorded on a Hydrothermograph placed in the center of the study 
site. Wind speed and direction were recorded only for the first two 
dates because wind was found to be negligible within the understory 
(also see Biere & Uetz 1980). 
Traps were taken to the laboratory, where the insects were 
removed (by individually placing a trap in a large porcelain pan 
containing pure kerosene). This dissolved the adhesive and facilitated 
the removal of even the smallest insects. After the insects were 
removed and placed in labeled vials, the screen was cleaned by 
blowing the kerosene off with an air hose, rinsing it under hot water, 
air-hosing the water off, wiping the frame dry, and then placing the 
screen on absorbent paper for at least four days. No odor of kerosene 
could be detected at this point and further applications of adhesive 
stayed on with no apparent problems, so we felt confident in the 
re-use of traps. Insects were identified to order and their length was 
recorded with a micrometer to the nearest 0.5 mm. 
The visibility of ASW’s is a potential problem with their use, but we 
minimized this effect by using clear, nylon thread and a large frame 
size. Besides functioning in the same way as real webs, ASW traps 
have advantages over other sampling techniques that add to their 
usefulness in the field. Primarily, they allow an air-flow that is not 
