lii Depaktmknt oi-^ Experimental Plant-Breedinc. 



by Mr, H. II. Love, and the results are now in manuscript ready 

 for publication. In general, the conclusion reached is that high 

 feeding does increase the range of variation, but the true value of 

 such variations in breeding has not yet been fully determined. 



2. Test of unbalanced fertilizers on variations. 



3. Tests of various chemicals not considered as foods, on varia- 

 tions when fed to the plant as solutions applied to the soil. 



4. Efifect of marked changes of soil. 



5. Effects of chemicals injected into the developing buds at or 

 about the time that the reduction division is taking place in the 

 formation of the germ cells. 



6. Tests of violent temperature changes applied about the time 

 that the reduction division is taking place in the formation of the 

 germ cells, or at other susceptible periods. 



In none of the above cases have the investigations reached con- 

 clusion, but important results have in some cases been obtained. 



One of the lines of investigation of the above nature has been 

 conducted on a somewhat extensive scale by Mr. E. P. Humbert, 

 an assistant in the department. This experiment consists in test- 

 ing the effect of chemical injections on pure-bred plants of one 

 of the wild silenes (Siloic noctiHora). Coupled with the study 

 of the injected material, a study is also being made of the varia- 

 tions which may be derived from pure strains. Something over 

 15,000 plants have been grown in connection with this experiment 

 the present season. 



Accompanying the investigation on the causes of variation, 

 studies are being made also on the extent of variation in many 

 plants as found growing in nature and in cultivation. An ex- 

 tended investigation has been made by Dr. C. F. Clark on the 

 range of variation in timothy, the observations being made in con- 

 nection with the timothy breeding experiments outlined above. On 

 a very large number of the timothy plants which have been grown 

 continuously for a number of years, careful notes have been made 

 each year on the date of bloom, duration of bloom, height of plant, 

 yield, etc.. and the same notes have been taken continuously on 

 the same plants for three to five generations. These data have 

 been brought together to show the extent of seasonal or place 

 variations. The manuscript of this investigation is completed and 

 awaiting publication. 



Studies on the laws of inheritance. — In connection with the 

 plant-breeding work, studies on the laws of inheritance, which arc 



