IMPROVING SELF-FERTILIZING CROPS 



133 



isolation of desirable forms. This was done at the Svalof Station. 

 The selections, Klock 1 and Stormogul, maturing early and late 

 respectively, were obtained. Both possess stiff straw and Storm- 

 ogul has good yielding ability. The improvement of the latter 

 character was sought by crossing with higher yielding light 

 colored forms. The following diagram indicates the method 

 followed. The varieties and strains were purified before the 

 crosses were made. 



Svart Tartarish Plymhafre 



Milton (Probsteier type) 



I 

 Klock I (1901) X Guldregn (1903) 



I 

 Stormogul (1901) X Klock II (1909) 



Klock III (1917) 



Klock II is the result of crossing a good-yielding black oat of 

 stiff straw (Klock I) with a high-yielding yellow oat (Guldregn). 

 The offspring has the stiff straw of Klock I and the high-yielding 

 ability of Guldregn. One selection in the cross of Klock II with 

 Stormogul gave a strain, Klock III, which has the early maturity 

 of Klock II, a somewhat higher yielding ability than Stormogul, 

 as well as non-lodging ability, which last character both parents 

 possessed. In Table XXX the yields of three of the strains 

 are shown. 



TABLE XXX. RESULTS OF COMPARATIVE YIELD TRIALS OP THE VARIETIES 



KLOCK II, STORMOGUL, AND A SEGREGATE KLOCK III OF A CROSS 



BETWEEN STORMOGUL X KLOCK II AS OBTAINED AT SVALOF 



FROM 1912 TO 1916 



