16 



BULLETIN 162, U. S. DEPARTMENT OF AGRICULTURE. 



numerous individual trees bearing nuts of sufficient merit and in 

 sufficient quantity to justify their being propagated as new varieties 

 of special promise for this section. 



Twelve standard varieties are growing at this station. The original 

 experiment embodied 19 varieties planted in 1909. These are being 

 tested with much care under good dry-farming conditions. Such 

 results as are indicated here, together with wide and varied obser- 

 vations of the nat- 

 ural home of bear- 

 ing trees and the 

 behavior of compar- 

 able plantings in 

 other situations, all 

 indicate that care 

 should be exercised 

 in selecting loca- 

 tions for pecan 

 plantings. Success- 

 ful tree growth and 

 fruiting should not 

 be expected when 

 the pecan is planted 

 in a soil where un- 

 derground water is 

 not within reach of 

 the roots. The sur- 

 face application of 

 water on most of the 

 higher land of this 

 section does not ap- 

 pear to fulfill the 

 needs of the pecan. 

 As the tree ap- 

 proaches bearing 

 age, the roots must 

 penetrate deeply 

 into soil which is 

 drawing water from the underground water table: then the pecan 

 succeeds and grows to be the most stately tree of Texas. The conten- 

 tion advanced by some enthusiasts that since the pecan is native it 

 can be grown under a great variety of conditions is erroneous. It 

 should be borne in mind that the pecan in this part of Texas is dis- 

 tinctlv a river-bottom tree and that the mere application of light sur- 

 face irrigations sufficient for many other trees will not satisfy its needs. 



Fig. 5.— A tree of Diospyros kaki, or Japanese persimmon, which is nearly 

 dead from chlorosis. This tree has been in its present location for eight 

 seasons. The only persimmons that have been found that are resistant 

 to chlorosis and root-rot are the native Diospyros texana and I), lotus. 

 Compare with figure 6. (Photographed September 16, 1913.) 





