June, 1942J Agricultural Experiment Station 11 



LITTER USED 



An attempt was made to use a series of various kinds of litters 

 throughout the experimental period so as to include as far as possible 

 all commonly used types. Those for tlie plot house were maintained 

 throughout the test period as originally set up, as given below : 



List of Litter Samples as Used in Plot House 1939-41 

 Plot Number Litter 



21 Sawdust 



22 Stazdry 



23 ' Peat Moss and Shavings 



24 Hay 



25 Shavings 



26 Servall 



27 Peat Moss 



28 ' Peat Moss and Straw 



29 Oat Hulls 



30 Straw 



31 Sand and Gravel 



32 Sand, Gravel, and Straw 



The variations in type of litters used according to pens are listed 

 in the pen summaries in Tables 4, 5, and 6. 



DISCUSSION 



In Tables 1 and 2 the monthly averages of the moisture content 

 of poultry pen and plot house litters is given as found during the 

 three year experimental period. It will be noted that during January, 

 February and March the pen litters had the greatest moisture con- 

 tent. Likewise, the late fall and Avinter months were of greatest in- 

 fluence in raising the moisture content of the Plot House litter sam- 

 ples. This shows that the fall and winter months, the normal period 

 of high atmospheric moisture, are the most critical in control of mois- 

 ture in poultry litters. 



The peat moss litter absorbed and retained the highest moisture 

 content of any of the litters used. Sand and gravel both in the poultry 

 pens and plot house absorbed and retained the least moisture through- 

 out the experiment. 



A question may be here raised, therefore, as to whether it is more 

 desirable to select for poultry litter one having a relatively high ab- 

 sorptive capacity for water which retains absorbed moisture or one 

 having a low absorptive capacity and a low moisture retention value. 



Several tests were made of the moisture holding capacity of the 

 different plot house litters. These results can only be considered ap- 

 proximate, but give an indication of the relative absorptive values. 

 These results are presented in Table 3. As shown, the figure is a 

 ratio of the weight of water absorbed to the dry weight of the sample. 

 Thus for peat moss the figure 4.5 indicates that 100 grams of peat 

 m.Oss would hold 450 grams of water, or 4.5 times its own weight. 



