36 The Colorado Experiment Station. 
low the surface of the soil. Wooden or iron stakes are used to hold 
the boards in place. 
Manure for Hotbeds .—The heating material most commonly 
used is fresh manure from grain-fed animals—horses or mules. It 
is better to secure it from a livery stable, as larger quantities can be 
gotten within a short time. As much as one-third or more of the 
manure may consist of straw or litter used in the bedding. If the 
manure has less straw or litter than this, it will be too dense and will 
not heat well and if it contains too much, the period of heating will 
be shortened. The manure is taken from the stable and placed in a 
flat-topped pile four or five feet high and as long and wide as nec¬ 
essary. If the manure is dry, it should be moistened by sprinkling, 
but must not be made too wet. Under normal conditions, it will 
start heating in four or five days. If the weather is cold, it may be 
necessary to sprinkle a part of the pile with hot water in order to 
start fermentation, or a small quantity of hen manure placed in one 
part of the pile will sometimes cause it to begin heating. 
When fermentation has progressed for a short time the pile is 
turned in order to make the heat uniform throughout. It may be 
necessary to turn the pile two or three times. When it is steaming 
uniformly throughout, the manure is ready to be put in the hotbed. 
The period between the piling of the manure and the time when it is 
ready to put into the bed is ordinarily about two weeks. • 
In putting the heating material into- the hotbed, the amount used 
depends on the outside temperature. If zero or colder weather is 
expected, manure to the depth of 18 to 30 inches should be put in 
the bed. For milder temperatures less can be used, and where there 
is only three or four degrees of frost, six or eight inches will be suf¬ 
ficient. The material is best put in by layers, each layer a few inches 
deep, and well tramped down with the feet before the next layer is 
put in. 
When the necessary amount of heating material has been put 
in and well packed down the bed is then ready for the soil. Soil 
made of one-fourth sand, one-fourth well rotted manure, and one- 
half good garden soil will answer very well. It is spread over the 
heating material to a depth of five to seven inches, the greater depth 
being desirable for radishes and other root crops. If plants in pots 
or boxes are to be put in the hotbed, sawdust or sand may 
be used instead of soil. Plants in pots are plunged to the rim in the 
sawdust, while boxes are simply set on it, the sawdust or soil, either 
of which can be used, being only three inches deep in this case. 
Temporary Hotbeds .—A temporary hotbed may be made as 
follows: Construct the walls of the hotbed of one-inch instead of 
