18 
Taser 2.—IJncrease of Mexican boll weevil when one-half are destroyed by application of 
methods recommended for destruction. 
Uninjured 






Number | 5auares | Squares Squares 
Month weevils | eaten per produced | squares | produced 
: per acre, |220nth per|permonth| left per | per plant 
: acre. per acre. month. |permonth. 
Warder es eee clcerinsce=bs BS eee cpa 2 | 60 8, 300 8, 240 1 
{ aol | 
Wuiae 14 5et tec aie ee rt eee ea 25 |, a30 41, 500 40,720 5 
| 780 | 
| f 9, 000 | 
Tuy te eee een eRe ebb 4 2 300. |: 2360 83, 000 73, 640 10 
| 9, 360 | 
| 112, 500 
AVIE TIS Gee eee oe es ON eee Sa Ee ret 3,750 |) & 4,500 249, 000. 132, 000 30 
| 117, 000 
1, 406, 250 | 
Septeniber Goes: stein sect ale ONE A 46, S75: (9) Os 200 NUS avg OpOn |e. oe ee 50 
1, 462, 500 | 
Ro teal Urata sae ss erste ee es ered Se epee ice Ey) RRO e 254, 600 96 
| 





aNumber of squares injured during the month by females left over from previous months. This 
is half the entire number for that month feeding at the rate of one square per day. 
b The tctal of uninjured squares is for August 1, and that of squares produced per plant is for Sep- 
tember 1. 
NORTHERN-GROWN COTTON SEED AND EARLY-MATURING 
VARIETIES. 
Attention has already been called to the advantage of securing 
squares on the plants as early as possible in order to confine the egg 
laying and the gathering of infested squares to the trap rows. This 
is easily accomplished either by planting cotton seed grown in a lati- 
tude as far north as practicable, or by planting extra early fruiting 
and maturing varieties. 
There is another important reason why the same principle should be 
adopted in selecting the seed to be used for the main crop, planting of 
which follows the trap rows. From Table 1 it can be noted under rate 
of increase that it requires the early portion of the season up to mid- 
summer for the weevils to breed and become numerous enough, even 
if given full sway, to produce one weevil for each square that the 
plant can produce. It is well known in the Brazos and Colorado river 
bottoms that home-grown seed produces plants whose tendency is to 
make a large and vigorous growth early in the season and to set its 
crop of bolls later. Hence, it does not begin setting much fruit until 
July, which, according to Table 1, is the time when the weevils have 
become numerous enough to prey upon each square as it is produced. 
Extra early varieties, or the same varieties with seed obtained from 
farther north, begin fruiting freely three weeks to a month sooner, 
and set a fair crop of bolls beyond the reach of boll weevils previous 
to the month of July. Seed from Indian Territory planted in the 
Colorado River bottom in Colorado County, Tex., has been observed 
to set fully enough bolls for one-half bale per acre by the middle of 
Le Sele b hoe 
lt ie at mien 
