INFLUENCE OF CULTUKAL COM dlU ).\S. 



49 



Tahi.!-; W. —Kij)l(in(ili(>n of Ktridtlmi in h m ju ratiiiu' (//ic/.s- <// llnIJ, Itsiillr ami 



hTrrnUh, Trr. 



Ti'inpcrutun.' fundi tions. 

 Absolute max- 1 



imiira. 



Avorago. 



Hallf'ttsvUlo. 

 Kt'rrville 



II 





95.0 

 g5.3 



"F. 

 74.1 

 69.5 



Si 



c 

 2 



KaililMllan.l.'l.Mi.l 

 Kdiiifjil. 



1 6 



84.6 

 82.4 



a 













0-: 





fe- 





::3 

 -^1 









= c 



, -^ 





♦J 



-4 1 



p. 



"3 



111 



ic 1 



o 





•;;e 



Q 



E- 



Q 



"F. 



7n. 



Inches. 





+ 1.1 



0.85 



-1.54 



:j 



.+ 1.2 



3.47 



+ 1.90 



5» 





3 a 



Sucli (liir(>r('nc(\s as tli()S(> shown in i-ainfall and cloud conditions 

 art' (Mitiridy sullicicnt to cx|)lain the diUVi'cncc in th(> cO'cct i\ cikvss of 

 -iniihir ninximuni ttMupcratiin^s. 



At Cucro th(^ month of »lunc was cxtrcnudy liot and (h\\ .show iiiL^ a 

 tcinj)(M*atiirc av(M-aicin<; 4.6 degroos above normal and i-ainl'all 2.01 

 inches below noi'inal. Those conditions are ])robably res])()nsible for 

 the major j)ortion of the cro]^ that was set in that locality. Durini^ 

 July there was an excess of rainfall amounting to 2.0.'^) inches, while 

 during August the excess amounted to 0.77 incli. While the mean 

 average temperature for August was 1 degree below normal, ihc 

 nu^in maximum tem])erature ranged very high. In this case it 

 ap])ears tliat the mortality from heat or drying, amounting to 20.5 

 per cent, was due not so niucli to drought as to the fact that the 

 maximum temperature ex])erienced during the month reached 95 

 degrees or higher upon nineteen days. In this case, aj)parently. heat 

 may have been the important factor rather than drying. 



At Waco, Junction, and Victoria, Tex., the mortality is very 

 evenly divided between heat and ants, the excess at W^aeo being due 

 to a much larger percentage of parasitism. At Brow^nsville a large 

 proportion of the mortality appears to have been due to heat, and 

 this would seem to be a natural condition for that locahty. 



The study of the data shown in Tables VII and VIII for the locali- 

 ties in Group B indicates similar conclusions for those shown for 

 Group A. At ^lineola, in a total mortality of 51.4, 31.5 ])ei- cent was 

 due to heat or drying, and the remarks state that it was "very dry 

 and hot" at the time the collection was made. 



At Trinity, with 50.5 per cent mortality, but 10. 1 ])er ceni was due 

 to heat, wdiile the destruction of stages by ants amounted to .17.7 per 

 cent. The remarks show that although a large portion of the leaves 

 had fallen from t\\v plants because of a fungous disease, the excessive 

 amount of raiid'all would naturally pi*e\'cnt a larg(> mortality from 

 heat or drying, while tlie |)resence of "many vSoleno|)sis" dii'ectly 

 explains the large j)roportion of the total mortality which was due to 

 1157.5— Bui. 74—07 4 



