BUKEAU OF PLANT INDUSTRY. 315 



excellent satisfaction in the southern half of Wisconsin and of ^Michi- 

 gan. U. S. Selection 136, introduced from IMexico in 1901 by Dr. 

 S. A. Knapp, has been under process of acclimatization and improve- 

 ment in production at "Waco, Tex., for six years in cooperation with 

 local corn growers. It is now grown by farmers about Waco, 

 Brownsville, and other portions of Texas, and to some extent in 

 Arizona and southern California. It continues each 3'ear to produce 

 best, or second best, in comi:'arison with other introductions, cross- 

 bred and pure-bred types, with which it is tested in dry, hot localities. 



Testing methods of corn breeding. — The various methods of corn 

 breeding that have been put to practical tests during the past ten 

 years are showing their comparative merits. The yields of this fall 

 will show the relative production of corn that has been undergoing 

 improvement by different methods of close breeding and crossing. It 

 is well established that the retention of half the seed of ears tested as 

 to jDroduction is important. It allows further testing under differ- 

 ent seasonal conditions and isolation or crossing of individuals of 

 improved merit. Indications have been foimd that power to yield 

 well is with corn a Mendelian character and that when two homo- 

 zygous individuals, related or unrelated, are mated the progeny 

 produces heavily. 



Determination of most profitable varieties. — Tests of produc- 

 tion made during the past year in cooperation with about 500 farmers 

 have brought forth many reports showing greatly increased yields 

 from well-selected and well-adapted strains of corn. Corn growers 

 desirous of making accurate tests to ascertain what A-ariety can be 

 most profitably grown are furnished with advice, as well as record 

 blanks, and in certain localities seed of some of the improved varieties 

 developed by the Department. 



Plans for future work on corn. — The gratifying and valuable 

 results that have followed the production by breeding and adaptation 

 of high-yielding strains of corn make an extension of the work desir- 

 able. It will not be possible for the corn-breeding experts of the 

 Department to breed high-producing strains for each locality, but it 

 is desirable that their broad knowledge and experience be utilized in 

 producing such strains in distinct portions of the United States. 

 Such strains can be taken up by private corn breeders for more local 

 adaptation, as is now being done wdth the strains already developed. 

 There is need for an extension of corn-breeding work into the rich 

 delta country of the lower Mississippi River, into Pennsylvania, Xew 

 York, the rich muck lands of Florida, the semiarid regions, and the 

 extreme Northwest. Such work would greatly increase the profit on 

 the acreage already devoted to corn in those sections. 



TOBACCO INVESTIGATIONS. 

 SCOPE OF THE INVESTIGATIONS. 



During the past year the tobacco investigations of the Bureau, in 

 charge of Dr. W. W. Garner, Physiologist, have included work with 

 most of the principal cigar, mnnufacturing. and export types, cover- 

 ing ten of the leading tobacco-producing States. The work has been 

 confined to the established tobacco districts and no effort has been 



