A megaphone -shape trap was developed in Indiana about 1950 to use a 100 -watt 

 mercury vapor lamp. It was the trap and lamp used in studies in Texas in 1952, when 

 the pink bollworm moth was found to be attracted to a lamp. 



Use of the BL lamp for survey purposes required a change in design because of the 

 lamp length. Several such traps equipped with a 15 -watt BL lamp were furnished to 

 entomologists in several States and some may still be in use. Chief advantage was in 

 low first cost but it was not entirely satisfactory because of its unidirectional design. 

 We still list it as a useful survey trap. 



A modified Minnesota European corn borer trap, equipped with two 15-watt BL lamps 

 mounted horizontally as attractants, was developed in Iowa about 1954. This type was 

 found to be much less effective in capturing European corn borer moths in 1958 than a 

 trap without roof and one 15-watt BL lamp mounted vertically. 



This roofless trap was developed primarily by J. P. Hollingsworth in Texas in 1953 

 for survey of cotton insects, particularly pink bollworm. One 15-watt BL lamp is the 

 attractant. The metal collecting chamber is designed so that rain passes through and 

 drains out of the bottom. 



Three of these traps have been used in early pink bollworm survey studies in Texas: 

 (1) trap with one 100-watt mercury vapor lamp (fig. 1); (2) unidirectional trap with one 

 15-watt BL lamp (fig. 2); and (3) trap with three 2-watt argon lamps (fig. 3). 



A survey trap of the same design as one shown in figure 3 was used in late 1958 and 

 195 9 by the Plant Pest Control Division in Arizona, Nevada, California, and Mexico 

 for pink bollworm survey. 



A modified type of this trap equipped with one 15-watt BL lamp has been supplied 

 to entomologists for survey purposes in 24 States. Most of them are used for checking 

 time of emergence and abundance of 10 common economic pests. Results reported are 

 published weekly in the Cooperative Economic Insect Report. Considerable interest has 

 been manifested recently by entomologists and engineers in the Middle West in the 

 formulation and adoption of standards for: (1) Survey trap design, (2) trap installation, 

 and (3) analysis of catches. 



Light traps, designed to control insects, may be grouped into three types: Electric 

 grid, suction, and mechanical. In general, light traps have not been recommended for 

 control purposes, although they are used on small acreages of high-priced crops, around 

 paper factories where night-flying insects must be controlled, at outdoor fruit stands, 

 and around dairy stables and milkhouses. 



The light trap with electric grid is flat or a hollow cylinder surrounding the lamp. 

 All of the lantern type have used an incandescent lamp except that developed by Herms 

 in California in 1935. The flat grid type has been used where BL lamps are used as the 

 attractant (figure 4). Our field investigations on possible insect control with such traps 

 have revealed serious clogging of the grids with heavy flights of European corn borer 

 in cornfields or Heliothis zea in either cornfields or cottonfields. The majority of such 

 traps have 3/8-inch grid spacing with impressed voltages of 3,500 to 4,500. Taylor 

 experimented in Indiana during 1950 with a l/2-inchgrid spacing and higher grid voltages 

 with less grid clogging. However, leakage through the supporting insulators developed at 

 the higher voltages, thus creating a new problem. He published the requirements of a 

 suitable insulator for a higher -voltage grid in 1951, but thus far no known changes have 

 been made by manufacturers in grid voltage. 



Experimental work at Oxford, N. C., in 1949, on hornworm attraction to ultra- 

 violet lamps also disclosed shortcomings of the electric grid trap as a killing device. 

 Hornworm moths attracted to the BL lamps were merely stunned by the grid and would 



