4 
the public wealth from production would be only faintly indicated 
by the above figures. 
There are many complex factors involved in the use of water 
in irrigation and the amount of water that may be necessary. Some 
water is required for the needs of the plant and is removed with the 
crop; a greater amount is evaporated from the foliage during the 
growing season; some is evaporated from the ground, and a cer¬ 
tain proportion sinks into the ground and passes away as ground 
water. In general, there are also losses, so far as the individual is 
concerned, in the excess water which runs over the surface. But in 
careful irrigation and under the pressure of necessity this becomes 
less and less. In a ditch system there are also the losses of carriage 
from evaporation and from seepage. So far as the plant is concerned 
some of these losses are unnecessary, but are incident and perhaps 
necessary to our ways of supplying it to the plant. Could we know 
the amount of water required in each of these ways, we should know 
in which direction there would be the greatest chance for improve¬ 
ment. A full investigation of the question would involve a deter¬ 
mination of the losses in each of these directions, but the determin¬ 
ation is one of great difficulty, and the results are not definite 
enough to report at present. 
The observations and measurements which are here reported 
are some of those made during the past three years in the Cache-a- 
la-Poudre Valley, one of the first valleys in the State to be developed. 
The results are principally from the records of self-recording instru¬ 
ments. These were placed so as to record all the water which passed 
through weirs, which were so placed as to measure all the water ap¬ 
plied to various crops. Instruments have been placed so as to 
measure the water applied to crops of potatoes, of alfalfa, of clover, 
of native hay, of wheat, of oats. The depths as used by some of 
our best farmers are given in the following tables and diagrams. 
We have the record of three seasons of the amount of w'ater used by 
the Cache-a-la-Poudre Canal Co. No. 2, one of the original Greeley 
Colony canals. From the skill of the farmers drawing water from 
it, and from the fact that it is one of the original Greeley Colony 
canals, it perhaps best represents what would be the practice of skillful 
farmers in the valley when water is supplied to them as they desire 
it. One season’s record of the New Mercer could not be definitely 
reduced, owing to the fact that most of farmers use water from a 
neighboring canal, and the waters could not be separated. 
The experience gained in these measures has shown the diffi¬ 
culties to be encountered, and will enable us to make the determin¬ 
ations of the future more satisfactory. But though confessedly in¬ 
complete, the importance of a more general knowledge of the subject 
makes it desirable to publish such results as we have. It is hoped 
that it may lead many individual farmers to undertake more care¬ 
ful observations on the amount of water which they use, and meas¬ 
ure it with more care. The observations undertaken by this section 
