364 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 8 



Check Plot 



Row 1 . . . 



2 



0 



4 



7 



8 



12 



7 



9 



18 



10 



20 



51 



45 



9 



10 



9. . . 



0 



0 



2 



6 



2 



20 



6 



17 



21 



6 



62 



111 



60 



30 



16 



17. . . 



1 



1 



1 



9 



4 



8 



18 



24 



37 



11 



77 



108 



62 



47 



18 



25 . . . 



2 



0 



6 



5 



9 



34 



24 



34 



24 



46 



78 



87 



88 



26 



30 



33. . . 



0 



2 



2 





6 



40 



15 



25 



33 



80 



112 



61 



62 



24 



20 



41. . . 



1 



1 



2 



20 



7 



32 



21 



29 



54 



29 



150 



123 



125 



34 



17 



49. . . 



1 



2 



7 



22 



9 



31 



17 



32 



37 



67 



124 . 



150 



84 



33 



12 



57. . . 



0 



0 



0 



17 



4 



18 



12 



25 



53 



99 



146 



140 



67 



8 



22 



65. . . 



0 



1 



3 



19 



9 



31 



18 



42 



70 



100 



185 



136 



169 



27 



21 



Total 



7 



7 



27 



112 



58 



226 



138 



237 



347 



448 



953 



967 



762 



238 



166 



It was at first proposed to count, at intervals of several days, the 

 number of injured terminals on six rows inside the enclosure and on 

 six rows of equal length on the check plot outside of the enclosure. The 

 number of trees in each of these rows was therefore counted and the 

 percentage of injured terminals was to be determined. The number of 

 injured terminals was counted at intervals of 3 or 4 days but it was found 

 that by the twenty-ninth of July about 75 per cent of the trees on the 

 inside of the enclosure and of those in the check plot had been stung 

 and the counts were discontinued. The number of injured trees 

 increased at about an equal rate in both the enclosed and the check plot. 

 The nursery was visited again on November 8 and there was about 95 

 per cent injury both inside the enclosure and on the check plot. 



At the time the fence was erected the number of tarnished plant-bugs 

 w^hich had appeared in the nursery blocks was negligible. By examin- 

 ing the totals in the above table it may be seen that during the period 

 in which it was under observation the fence did keep out many of 

 the tarnished plant-bugs, in some cases over 50 per cent, but from the 

 final condition of the trees inside the enclosure as seen on November 

 8 not enough had been excluded to make its use worth while. 



The behavior of these insects on the fence was carefully observed 

 from day to day. It was found that very few of the bugs would alight 

 on the fence higher than three feet from the ground. The}^ would 

 then make their way to the edge of the tanglefoot by walking or by a 

 series of flights of six or eight inches each. From this point it required 

 but a short flight to carry the insect over the width of the tanglefoot 

 and into the enclosure. Some, of course, did not act in this manner but 

 after walking or flying about a little returned to the weeds or peach trees. 



