THE PKODUCTION OF POTATO SEED TUBERS BY MULCHING. 



Report of tlie Committee on Vegetiibles. 



By R. A. Emerson. 



There is a general impression among the potato growers of Nebraska, 

 particularly among those of the southern part of the state, that it is an 

 advantage to secure seed tubers from the North at least oncey every 

 two or three years. In other words, many potato growers believe that the 

 potato deteriorates when grown in southern Nebraska from the same 

 stock of seed year after year. Experiments carried on at the Nebra-ska 

 Experiment Station, as well as experiments reported from other places, 

 indicate that there is a basis for this belief. About five years ago the 

 Experiment Station secured some Early Ohio potatoes from the Red 

 River country of Minnesota, a region which has the reputation of pro- 

 ducing very good seed stock. This same stock of Early Ohio has been 

 grown at the Experiment Station every year since. Two or three times 

 since getting this original stock we have brought in Red Ohios for com- 

 parison. During the past three or four years, the potatoe stocks direct 

 from the Red River country have yielded decidedly better than the 

 Experiment Station stock, which, as noted above, came originally from, 

 the Red River country. In other words, the Red River stock seems to 

 have deteriorated by being grown in the vicinity of Lincoln for a few 

 years. 



The explanation commonly offered by potato experts to account 

 for such deterioration as that noted above when potatoes are grown in 

 the South is something like this. The potato is naturally a cool weather 

 plant. It is supposed to have been native in the high plateaus of South 

 and Central America. In these regions, while the days are hot the nights- 

 are invariably cool, owing to the elevation. Similar conditions are ap- 

 proached in the northern States of this country. It is certainly true that 

 the potato succeeds better in the cooler climate of the Northern States 

 than it does in the warm climate of the extreme Southern States. It is 

 certainly also true that the hottest part of the day is of shorter duration 

 in the North and that the nights are distinctly cooler. It is also true 

 that the soil temperatures are in general lower and doubtless more uni- 

 form in the North. 



Some years ago it occured to me that if northern-grown seed was: 

 better than home-grown for the reasons noted above, we might be able 

 to grow seed tubers in this region successfully by imitating more northern 

 temperature conditions. This might be accomplished in part, it was 

 though, by very deep planting, so that the tubers, forming somewhat 

 deeper in the ground, would be subjected to lower and more uniform tern- 



