EXPERIMENT STATION BULLETINS. 339 



may be applied broadcast or in the furrow. When applied broadcast, they 

 are spread by hand, by a grain drill, or by special fertilizer sower after the 

 soil has been thoroughly fitted and shortly before the potatoes are planted. 

 After the fertilizer has been broadcasted it should be harrowed into the 

 moist soil. When potatoes are planted with a machine having a fertilizer 

 attachment, the fertilizer may be sown in the bottom of the furrow. It 

 should be distributed in a wide strip, and should be mixed with the soil so 

 that the growing sprouts and roots will not be injured by it. In sections of 

 the state that are subject to drought, it is not generally advisable to apply 

 fertilizer in the furrow at heavier rates of application than 300 to 400 pounds 

 to the acre, since heavier applications may cause injury to the young plants. 



VARIETIE.S 



The standardization of potato varieties is very important. Michigan 

 potatoes have in the past been discriminated against in many instances be- 

 cause of lack of standardization in uniformity of varieties and grades. The 

 markets cannot handle car loads of mixed potatoes satisfactorily, and for 

 this reason it is desirable that not more than one early and not more than one 

 late variety be grown in a community. 



Observations and tests over the state, from both the production and market 

 standpoints, indicate that the following varieties are to be recommended: 



Early 



1. Irish Cobbler. 



2. Early Ohio. 



Late 



1. Late Petoskey (Russet Rural) (Petoskey Golden Russet). 



2. White Rurals, including Rural New Yorker No. 2, Sir Walter Raleigh, 



and Carman No. 3. 



3. Green Mountain. 



The Irish Cobbler matures early. The vines are medium in size, having 

 rather short jointed, dark green stems and large, medium dark green leaves. 

 The flowers are light purple or rose lilac, though under hot weather conditions 

 they may be nearly white. The tubers are roundish and often have the 

 stem end rather deeply notched. The eyes vary from shallow to deep, par- 

 ticularly in the seed end. The skin is smooth and of a light, creamy-white 

 color. The sprouts are reddish violet or magenta. This variety is of good 

 quality and gives a fair yield under good growing conditions. 



The Earhj Ohio matures a few days earlier than the Irish Cobbler. The 

 yield, however, is generally somewhat less. The vines are rather erect with 

 dark green stems. The flowers are white. The tubers are round-oblong 

 with full, rounded seed and stem ends. The eyes are rather shallow but 

 when grown under unfavorable conditions they tend to develop knobs. 

 The skin is light pink with small, corky dots. The sprouts are carmine-violet. 



Seed potatoes of the Irish Cobbler and Early Ohio varieties are in demand 

 by growers of the southern states. Thus far Maine, Minnesota and Wis- 

 consin have been supplying the bulk of this early seed. 



The Bliss Triumph is a very early variety that is grown to some extent in 



