6 X. II 1-:XPKR1MEXT STATION 1 bulletin 320 



Table 5. — Average yields in 3 grass pastures, 1931 



Pounds per acre Pounds per acre 



Treatment Dry matter Protein Gain for Dry matter Protein 



untreated plots while the protein values are somewhat wider than 

 this. 



The grass pastures, Table 5, again exhibited a tremendous stimu- 

 lation from nitrogen, although in 1931 the plots treated with super- 

 phosphate alone showed up to a little better advantage than the 

 grass pastures of 1930. (Table 3). It may be well to point out that 

 the season of 1931 had considerably less rainfall than in 1930 which 

 doubtless accounts for lower relative yields on these lighter soils in 

 1931, since these are the first to suffer in a dry season. 



It can be readily seen, however, from a study of these brief tables 

 that the type of sward that develops under fertilization will in large 

 measure govern the response secured from the different materials. 

 Nitrogen showed good response on all these pastures in both years. 

 Whether a farmer should use nitrogen will depend upon whether he 

 needs more feed in the spring since the stimulation from this ele- 

 ment, applied early, will be secured mainly in May, June and early 

 July. Of course there is a possibility of using nitrogen fertilizers 

 later in the season and while the total response might not be as great 

 it luight still prove to be profitable if a serious feed shortage existed 

 on the farm in the summer or fall. 



The tal)les show also that returns from supt'r])h()S])hate, potash and 

 lime are likely to be governed b\- the presence or absence of clover 

 in the sward. Clovers respond more generously than do the grasses 

 to these substances while grasses are especially responsive to nitro- 

 gen. 



No tillage operations were practiced in these pastures and no seed 

 was sown. The vegetation that was there or that develo])C(l under 

 the various fertilizer procedures included the native grasses, Ken- 

 tucky Iduegrass, bent grasses, poverty grass, and other indigenous 

 plants along with wild white or native pasture clover. \'egetative 

 counts that were made on the plots during the time of their opera- 

 tion showed a distinct change from poverty grass and weeds to (he 

 better pasture types, Kentucky bluegrass and wild white clovir. due 

 to the rapid spread of these species at higher fertility levels. This 

 change was surprisingly rapid amounting to 50 per cent or more in 

 the course of one growing season. 



In selecting these pastures at the outset, an attempt was made to 

 choose as uniform a section of each one as possible and to get an area 

 free from brush so that it wouhl be feasible to mow small sections of 

 each ])lot at intervals to check yields. The ground where the plols 

 were located in each ca'^e \va^. therefore, coverefl with vecretation 



.-> ' 



