48 IXFLrENCE OF SiZE OF SeED ON YiEI.D OF POTATOES. [ApR., 



weights and numbers of tubers — see Tables II and III. It 

 appears that neither size, weight, nor external character of a 

 tuber set, influences the phenomenon of secondary outgrowths 

 in the potato crop. 



Although the tendency to produce secondary growth is 

 obviously not carried on by the tuber seed, nor influenced in 

 any way by the size of the set, it is, however, clearly a property 

 of larger, rather than smaller tubers of the crop. 



The results of the experiment so far as this first year allows 

 of conclusions are : — 



1. That although small chats give a great return in proportion 

 to their weight as seed, and produce as much, in this experiment 

 more, big ware as any class of seed, yet they are decidedly 

 uneconomical. 



2. The best seed class are tubers of 2 oz. in weight. 



3. Seed tubers over 2 oz. in weight give smaller crops whilst 

 the amount of seed used is progressively greater. The amount 

 of heavy ware is progressively less both actually and relatively. 



4. The tendency to secondary growth formation is not con- 

 veyed to the crop from the seed tuber. It is a peculiarity of 

 big tubers and is not directly influenced by the size of the seed 

 tuber. 



5. Seed tubers with secondary growth make exceedingly good 

 seed, and, apart from the fact that they are large and wasteful 

 without cutting, the evidence would tend to show that their use 

 as seed is strongly indicated. 



In conclusion it may be noted that the experimental results 

 as regards the best weight of tuber sets being 2 oz. merely con- 

 firms general experience. As to the value of tubers exhibiting 

 secondary growth as seed, it is the custom amongst the allotment 

 holders and others in this district to use, when cut as seed, those 

 tubers they exhibited in the local Flower Show for *' largest 

 size class, and which almost invariably are deformed by promi- 

 nent outgrowths, in the firm belief that they yield the biggest 

 crops and earliest crops of the particular variety. 



