362 



JOURNAL OF ECONOMIC ENTO^IOLOGY 



[Vol. 8 



^dthin a few days, their numbers increased rapidly. Accordingh^, in 

 order to have the fence up and in working order by that date, its 

 erection was commenced on the fifth of June. Ordinary wire screen 

 cloth 6 feet wide was used to enclose a rectangular area 470 feet by 240 

 feet which therefore contained 2.59 acres. This enclosure was placed 

 in a 13-acre block of peach ''buds." A narrow strip of ornamentals 

 bordered the fence on the west side; the other three sides were sur- 

 rounded b}^ peaches. 



Hickory posts 9 feet long were sunk 2 feet into the ground at intervals 

 of 10 feet. The wire screen cloth was then fastened to these uprights 

 with, heavy staples. In order to prevent any insects from crawling 

 through open spaces at the bottom due to irregularities of the ground, 

 the dirt was banked up firmly 3 or 4 inches at the base. At one corner 

 a flap of the wire was arranged so that it could be opened in order to 

 admit teams and workmen. Since the rows ran north and south, on 

 the inside at the north and south ends the trees were dug out for a 

 distance of about 10 feet in order to provide a turning place for the 

 mules and cultivator. 



It had been previously observed that though the tarnished plant-bugs 

 did not actually fly over the fence from the surrounding weeds or 

 nursery stock they would, however, fly onto the fence, crawl to the 

 top and then fly into the enclosure. In order to prevent this a strip 

 of 0. & W. Thum's Tree Tanglefoot about 4 inches in ^^ddth was applied 

 along the upper edge of the wire cloth. The method of application was 

 as follows: Two men worked together, one on each side of the fence. 

 Wooden paddles w^ere used, the ends of which were cut at an angle and 

 bevelled. The tanglefoot was applied from the outside and pressed 

 back and forth until a uniform thickness of about 1/10 inch was 

 obtained, the man on the inside always finishing so that the greater part 

 remained on the outside of the wire cloth. 



It took two men about an hour to put on such a band of tanglefoot 

 100 feet in length. A pail of tanglefoot containing about 25 pounds 

 covered about 300 linear feet. 



In another part of the nursery in which about 13 acres of peach 

 seedlings were planted, a similar fence was constructed but the enclosed 

 area was much smaller, the dimensions being 190 feet b}' 100 feet. 

 Most of the observations were made, however, at the larger enclosure 

 as it was nearer to the laboratory. This enclosure was completed on 

 the 12th of June and the smaller on the 16th. 



The cost of construction of the two fences together, including 

 materials and labor is shown in the follomng statement. 



