14 JOHNSON & STOKES 
Professor Roberts has suggested $250 per year as a con- 
servative estimate of the value of the manure produced dur- 
ing seven winter months on a farm carrying four horses, 
twenty cows, fifty sheep and ten pigs. The estimated value 
may be made much higher in cases where farmers are willing 
to use thought and labor in preparation and preservation of 
home-made manures. 
Solid Manure and Liquid Manure The urine is the 
most valuable portion of the excretion of animals, according 
co the tables of the agricultural chemists. It is especially 
rich in nitrogen, and, hence, its strong odor under fermenta- 
tion. It is also rich in potash. Its place is on the manure 
heap, not in a ditch leading to a brook. If it collects in 
quantities beyond the absorbing power of the manure pile, 
it should go on the compost heap or else be diluted and at 
once put upon the land. 
When to Fertilize.— The land is a good bank in which 
to deposit money in the form of manure; but there are cer- 
tain portions of the year when the land bank declares no 
dividends. It is safe to put manure upon an unfrozen soil at 
any time, but the best, the quickest, and the largest results 
are obtained by manuring during the growing season, pre- 
ferably just before planting the crop. Small applications, 
often repeated, are preferable to large, though rare, applica- 
tions. Plants, like animals, consume small amounts of food 
each day, and cannot take a year's food at a single meal. 
Humus — Humus, often referred to by agricultural writers, 
is a name for decaying organic matter in the soil. Green 
crops turned under, grass roots, stubble, leaves, long manure, 
etc., form humus. The term is a comprehensive one. Humus 
is a dark-colored substance, abundant in all rich ground. A 
lump of manure that has been lying in the ground for a year 
or two has become, practically, a mass of humus. 
Minute Soil Workers.— In all good soils there are 
