6 CIRCULAR 609, U. S. DEPARTMENT OF AGRICULTURE 
moisture in the compost. Very little loss of moisture takes place at 
this time because of the reduced differential between the manure and 
air temperatures. 
DURATION OF COMPOSTING 
The most satisfactory length of the composting period depends on 
the condition of the manure when it is put into the beds. Manure 
fresh from the stables undoubtedly should be composted a few days 
longer than manure that has been a week or two in a freight car en 
route to the grower. Likewise, manure that has been allowed to 
become sour by standing under anaerobic conditions will take longer 
to decompose, and manure that has been excessively wet will take 1 
or 2 days longer to reach a proper composted condition than manure 
that has been properly moistened before composting. 
At the end of indoor composting the criteria used to determine the 
suitability of the compost are much the same as those used by ex- 
TABLE 1.—Effect on yield of mushrooms of differences in duration of composting 
period and in amount of moisture in the manure at the time of filling 
EXPERIMENTAL DATA 
| 
Yield when approximate percentage of water to dry matter 
was— 
Days com- Bed 
posted No 200 250 300 Sums Mean 
(number) ; eee siaioiar Ie 
Single ; Single Single 
plots Mean plots Mean plots Mean 
Ounces! | Pounds? | Ounces! | Pounds ?| Ounces! | Pounds?| Ounces! | Pounds? 
1 258 | 268 225 
ae Ue OS 2 oot lata | ae 1.52 ne 0.99} 2,540 1.32 
4 208 | 182 154 
1 276 | 272 277 
10s eee z oO lhe e160, ae 1. 48 ae 1.52] 2,950 1.53 
4 271 | 106 246 ? 
1 293 | 309 212 
[oe Cees vce z ae 1.79 | 2 1.73 ae 136}. 39134 1.63 
4 265 | | 295 232 
1 256 | | 253 261 
i sgt latin z Ae 1.66 | pa 1.75 are 1. 40 3, 010 1.60 
4 255 259 210 
Gums mate aa la eee F156. |e ee | est QO) teak co Serene SeSR 7a (ose ee ones 11, 6340|2 2 ee 
Means’). | uae oereees ; 18 | hee TeGot| bees een 1.32)| = 
ANALYSIS OF VARIANCE 
| 
a nea thn Degrees of Sum of Mean 
Source of variation freedom squares square 3 
IBGtWEEMt MN OISUUITES Hee ae a ia eg ede cae ae ew 2 22, 734 **112366 
Betweenlen gthstofeCOnap os tira cay see eee eee eee 3 16, 555 SPH 51e 
MioisturespGlenethsiof Com postin geese eee eee see eee eee 6 9, 793 1, 632 
‘Between'ibeds (blocks) = =5 Stas eee eee ee ee ee 3 9, 723 3, 241 
Beds X<treatments (error) sata se See eee ee eee 33 40, 062 1, 214 
FTO Ge a a Ere ad ee ee 47 98, 867 
1 Per 10 square feet. 
2 Per square foot. 
3 **= Probably significant; odds greater than 99 to 1. 
