— 175 — 



All these figures are invaluable, it seems to me, in showing 

 that this is an entirely unreliable method of experimentation and 

 that isolated results are not to be depended upon. The variations 

 in these potatoes were no doubt due much more to the stock itself 

 — how it had been grown and handled in previous years — than to 

 any influences of latitude. In other words, I believe that it is 

 impossible to secure stock from different growers which is uni- 

 form enough to allow of comparative experimentation ; and this 

 is as true in other plants as in potatoes. If this generalization is 

 correct, we must modify many of our methods of experimentation. 

 In order to secure a uniform stock, it must be grown in the same 

 place and under the same conditions for several years, and this 

 can then be distributed to various growers and after a time re- 

 turned to be grown again side by side for comparison. And even 

 here it will be difficult to eliminate uncertainties. But in this 

 line we shall now work upon our studies of the influence of 

 latitude upon plants. 



NOTES UPON METHODS OF HERBACEOUS GRAFTING. 



My attention has been called a number of times to the unsatis- 

 factory records and directions concerning the grafting of herba- 

 ceous plants. There appears to have been very little attention 

 given to the subject, and the scant discussions of it are mostly 

 copied from one author to another. A few years ago I made some 

 attempts at herbaceous grafting, but it was not until last winter 

 that experiments were seriously undertaken. The work was put 

 in the hands of J. R. Lochary as a subject for a graduating thesis. 



The experiments were undertaken primarily for the purpose of 

 learning the best methods of grafting herbs, but a secondary and 

 more important object was the study of the reciprocal influences 

 of stock and cion, particularly in relation to variegation and col- 

 oration. This second feature of the work is still under way, in 

 one form or another, and we hope for definite results in a few 

 years. As a matter of immediate advantage, however, herba- 

 ceous grafting has its uses, particularly in securing different kinds 

 of foliage and flowers upon the same plant. There is no difficulty 

 in growing a half dozen kinds or colors, on geraniums, chrysanthe- 

 mums, or other plants from one stock of the respective species. 



