86 MINNESOTA STATE HORTICULTURAL SOCIETY. 



Red Rosa rugosa x Baby Rambler. 



Red Rosa rugosa x Mad. Plantier. 



General Jac x Rosa rugosa (Red). 



Mad. Plantier x Rosa rugosa (Red). 



No. 2654 X Rosa rugosa (Red). 



No. 2655 >^ Rosa rugosa (Red). 



The work with potatoes has been kept up for many }-ears. We 

 have aimed to select varieties that were disease resistant. Experi- 

 ments along this line have been continued the past year, and over 

 fifty varieties have been tested. 



In the study of the flowers which we have made we have at- 

 tempted to determine — if possible — why the potatoes did not set 

 fruit as formerly. This study has revealed the fact that our com- 

 mon varieties seldom produce healthy, plump pollen, and out of 

 over fifty varieties tested there were only seven or eight that had 

 normal pollen. These varieties were as follows : 



State of Maine, Washington, Green Mountain, Uncle Sam, Im- 

 proved Peachblow (best pollen), Irish Cobbler, Snow Ball, Ver- 

 mont Gold Coin. 



Trial Orchard, Minnesota State Experiment Station. 



We then attempted hand crosses between these varieties and 

 also crosses between them and a wild kind known as Solanum Com- 

 mersonii. These latter crosses produced about one hundred seed 

 balls. These seed balls were unusually large, but practically con- 

 tained no fertile seeds, there being only about four half-ripe ovules 



