528 Journal of Agricultural Research vol. vi, No. i 4 



occur. Rape contains a larger amount of sugars * and is therefore likely 

 to develop a high acidity. Rape, in common with other Crucif erae, con- 

 tains considerable amounts of organic sulphur compounds, which are 

 likely to form disagreeable volatile products if the fermentation pro- 

 gresses too far. For these reasons a mixture of rape and a legume 

 should produce better silage than either alone. 



EXPERIMENTAL RAPE SILAGE 



The experimental silage was therefore made from rape alone and from 

 mixtures of rape with various other materials, as outlined in Table I, 

 with the purpose of determining the most satisfactory combination. 

 The other plant materials used were alfalfa (Medicago saliva), red clover 

 {Trifolium praiense), sweet clover (Melilotus alba), potato tubers (Solatium 

 tuberosum), timothy (Phleum praiense), Sudan grass (Andropogon sorghum, 

 aethio picus) , sorghum cane (Sorghum -vulgar e), and bluegrass (Poa pra- 

 tensis). The rape used was quite mature but still succulent. The rape 

 leaves were cut off at the main stalk. The entire plant was cut 3 inches 

 from the ground. The alfalfa was cut just before blooming. The corn, 

 Sudan grass, and sorghum cane used were mature. The other plant 

 materials were cut just before maturity. All the forage was cut by a 

 silage cutter, into half -inch lengths. The material was tightly packed 

 into glass jars of about 1 -gallon capacity, in the same manner as corn 

 silage has repeatedly been made in this laboratory. The jars were closed 

 with metal caps, which were not too tight to prevent the escape of excess 

 gases. 



1 An average air-dry sample contains 5.60 per cent of total fermentable sugars calculated as dextrose. 



