24 



BULLETIN" 564, U. S. DEPARTMENT OF AGRICULTURE. 



Table 21. — Row records of infested squares collected with bag-and-hoop , Hecla plantation 

 experiment, Mound, La., 1916. 





Infested squares collected. 



Row No. 



June 16. 



June 22. 



June 29. 



July 10. 



July 17. 



1 



Row 

 total. 



Average 

 per row 

 in 5-row 

 blocks.i 



Average 



per row of 

 outside 



and inside 

 blocks. 



1 



22 



8 



13 



32 



13 



18 



19 



28 



13 



25 



44 



8 



24 



15 



10 



24 



9 



9 



18 



14 



9 



12 



23 

 14 

 28 

 29 

 12 

 11 

 19 

 26 

 8 

 33 

 28 

 18 

 23 

 18 

 23 

 23 

 18 

 23 

 22 

 16 

 20 

 12 



19 

 19 

 6 



36 

 23 

 28 

 27 

 15 

 28 

 24 

 35 

 14 

 22 

 29 

 21 

 51 

 19 

 11 

 20 

 19 

 30 

 15 



47 

 33 



5 



70 

 36 

 64 

 31 

 48 

 19 

 48 

 26 

 28 

 44 

 29 

 26 

 26 

 11 

 30 

 22 

 44 



7 

 23 



71 

 40 

 43 

 29 

 38 

 33 

 18 

 30 

 14 

 24 



4 

 23 

 11 

 18 

 16 



9 

 20 

 13 

 14 



2 

 12 



5 



182 

 114 



95 

 196 

 122 1 

 154 1 

 114 1 

 147 



82 

 154 

 137 



91 



124 ' 

 109 : 



96 

 133 



86 



96 

 95 

 78 

 67 



144.0 



• 127. 



• 110. 6 



S3. 1 





2 





3 





4 



144.0 







6 













9 





10 





11 





12 



> 118. S 



13 





14 





15 





16 





IT, 





IS 





19 





20 



83.1 



21 





22 







1 







1 Outside blocks each consist of 6 rows. 



Table 21 shows the row collections of the infested squares in the 

 same manner. An analysis of this table by blocks shows the square 

 collections to correlate very well with the weevil collections, the 

 number of infested squares decreasing with the increase in distance 

 from the check plat. In this connection it is interesting to note 

 that the highest record was in row 4, while the second highest was in 

 row 1 , so it is seen that the most highly infested rows were included 

 hi the 4-row buffer which was dropped. 



Considering these row records on the whole it is seen that the only 

 outside influence affecting the infestation of the picked plat was 

 ■apparently the migration of the weevils from the check plat. This 

 was sufficient in extent to increase slightly the infestation of the 

 side immediately adjoining the check and would undoubtedly have 

 some influence on the results secured. However, this migration 

 appears to have been comparatively unimportant, and consequently 

 its only effect on the results would be in the degree. That is, it 

 would not offset any beneficial effect from the bag-and-hoop collec- 

 tions, but probably would lessen the gam somewhat. 



LXFESTATIOX. 



The infestation of these various plats was followed throughout 

 the season in the usual manner. As has been mentioned, the weevil 

 abundance was determined from May 8 to June 5 by plant examina- 

 tions, the figures secured expressing the ratio of the weevils to the 

 plants. After June 5, however, the squares became sufficiently 



