This is further substantiated by the fact that when the soil in these 

 baskets is immediately replanted with wheat there is a decline in the 

 growth of the second crop of 50 per cent, especially where the soil 

 is untreated. With certain beneficial treatments, however, or by 

 re-treating the soil just before planting the yield may be maintained. 



RESULTS OF DIFFERENT MANURIAL TREATMENTS OF LEONARDTOAVN LOAM. 



In view of the fact that this soil is apparently deficient in organic 

 matter, it was believed that treatments with barnyard manure would 

 be especially beneficial. All practical farmers are of course aware 

 of the fact that there is considerable variation in the composition 

 of barnyard manure, and that its efficiency also depends upon its 

 state of decomposition. In order to get some results bearing upon 

 these points samples of manure Avere obtained from eight different 

 sources, and the above two samples of soil, as well as others, were 

 treated with these manures at the rate of 20 tons per acre. 



The following table shows the results of the experiment, the rela- 

 tive growth of plants being expressed on the basis of 100 for the 

 untreated soil in each case : 



Kffcct of manure from, different sources on Leonanltotcn loam. 



a In this and subsequent tables the actual relative growth on the untreated samples of 

 these two soils is 100 for the poor and 148 for the good, but the results of each treatment 

 are stated on the basis of 100 for the untreated soil to simplify the comparison of the 

 different treatments. 



The above results show that the efficiency of barnyard manure on 

 these soils is widely variable and that under certain conditions of tht 

 soil or of the decomposition of the manure it may actually be harmful. 

 The depressing effect of the sample of fresh horse manure can not 

 attributed to its lack of plant food constituents, for it was probably 

 one of the most concentrated in the series. It seems likely that some 

 product in the manure or the decomposition which took place ii 

 the soil gave rise to products that were somewhat injurious to the 

 plants. It is noticeable throughout the experiment with barnyai 



