yons, some of which maintain streams throughout the year, while others dry up about mid-summer. The foothills between the valley bottom and the first timber are covered with the common sagebrush (Artemesia tridentata), bitter brush (Kunzia tridentata), little rabbit brush (Gutierrezia diversifolia) and Indian Pink (Castilleia angustifolia). Among the forage plants of importance in these foothills are Anderson's clover (Trifolium Andersonii), the bigheaded clover (Trifolium macrocephalum), Sandberg's blue-grass (Poa Sandbergii), and Fendler's blue-grass (Poa Fendleriana). The gulches at one time had upon them a considerable quanity of Juniper, (Juniperus occidentalis) commonly called cedar, but most of it has been cut off for firewood and fenceposts. The region from 6000 to 8000 feet may be spoken of as the open yellow pine forest area. Very little old timber is now left in this area, the higher ridges containing only stumps. The canyons, however, are being rapidly reforested with a thick growth of pines (Pinus ponderosa) and firs. The white fir (Abies concolor) seems to be coming in more readily than the yellow pine and from a standpoint of reforestation for conservation of water it is more valuable. This species is being used in considerable quantities for paper at the plant of the Floriston Paper Company some 20 miles west of Reno. Higher up, and particularly on the northern slopes where the soil remains moist practically all the year around, there is an abundance of vegetation consisting chiefly of the common sunflower (Wyethia mollis), the big sunflower (Balsamorhiza sagittata), the little sunflower (Helianthus Nuttallii), tomato plant (Hydrophyllum alpestre), wild dandelions (Crepis intermedia), and Indian pinks (Castilleia miniata).

The denuded forest area is very quickly being covered with the little manzanita (Arctostaphylos nevadensis), the shrubby chestnut or chinquapin (Cantanopsis sempervirens), Indian carpet (Ceanothus prostratus), snowbrush (Ceanothus velutinus), and mountain currant (Ribes cereum), so that from a forest cover standpoint the soil will soon be protected from erosion.

This particular portion of the range is fortunate in that it is under the control of one sheep man who reserves it for his band of thoroughbred Shropshires so that every year the varieties that were once eaten out are gradually coming in again.

WEATHER CONDITIONS DURING EXPERIMENT

The experiments were begun on June 13th. The sheep were fed for two days on alfalfa before the experiments were started in order that

PLATE 1. Gathering Indian Potato Plants on the Range.

they might adjust themselves to the new conditions. The experiments proper began on June 15th and at first some little difficulty was experienced in accustoming the animals to the feces sacks. It would have been better to have placed these on the sheep a few days before beginning the actual experiments.

At this time the weather was cold with frequent squalls of sleet and hail. This weather continued until about the 21st, when the weather became warmer and severe thunderstorms, accompanied by rain and hail, were encountered.

It was at this time that the leaves were blown from the cottonwood trees into the pens and quickly eaten by the sheep. From this time on the weather was excellent, in fact by July 25th, when the experiments closed, it was decidedly warm.

METHODS OF FEEDING

In selecting a site to carry on this work, it was essential that a place be found with plenty of forage material at hand and close to water. An investigation was made of conditions on the range for the work and the location finally selected was in the foot-hills of the eastern Sierra Nevada Mountains in the vicinity of Hunter Creek Canyon, about fourteen miles west of Reno. Here we found the particular forage plants we desired to investigate in this first series. of experiments growing in abundance. Later a camp was established in the canyon of a small creek tributary to Hunter Creek, and feeding stalls constructed for the sheep. The stalls were made of rough boards, and built in a grove of cottonwood trees to afford shade. During the period of experiment the sheep were confined to separate stalls, each stall being nine by twelve feet in size.

Each experiment was preceded by a three days' preliminary feeding with the forage plant under investigation. This preliminary feeding served to determine the amount of fodder a sheep would eat, also to eliminate from the system material that was fed in the previous experiment. At the end of the three days preliminary feeding, the feces sacks were attached and the feces gathered for six days, in most cases the experimental period. The feces gathered were spread out in the sun to dry and then put into canvas bags. At the close of the experiments the bags were taken to the laboratory, the feces further dried, weighed, and prepared for analysis.

The fodder was gathered by hand, just before feeding-time, and fed in its green state. Samples were taken from each feeding ration, weighed, spread on drying sheets, and allowed to dry in a tent provided for that purpose, to protect the samples from the wind and dirt. When the samples were air-dry, they were weighed again and bagged, taken to the laboratory and there prepared for analysis.

For the most part all the forage plants fed were readily eaten by the sheep. It was noticeable, with few exceptions, that in changing from one forage plant to another the sheep at first did not eat well of the new fodder, seemingly to prefer the fodder fed in the previous experiment. In a few days, however, they came to feed readily on the new fodder, apparently with a relish. The only exception being in the case of Wild Vetch (Lathyrus coriaceus) which is discussed later.

A bucket of fresh water was kept constantly before the sheep, and about once a week each sheep was given a small portion of salt. Wethers, three years old, in healthy condition, were used in the experiments.

EXPLANATION OF TERMS USED IN THE TABLES

In all food materials, a part is undigested and is eliminated in the feces. Particularly is this true of the food of animals, which contains considerable amounts of nutrients that are unacted upon by the digestive juices, in its passage through the alimentary canal. There is constantly a breaking-down of the tissues which in the healthy animal is renewed by new material absorbed in the process of digestion. The waste from the broken-down tissues is thrown off from the body by being eliminated in the feces. Just how fast this breaking-down and rebuilding of body tissues is taking place is not known. There must be necessarily a slight error which cannot be avoided entering into the results of digestion experiments, but this error is very small and does not affect the results materially.

The digestible nutrients of a fodder are those absorbed from the digestive tract during the process of digestion. Their functions are to repair and build up the body. The undigested portions are eliminated in the feces. The amount digested is determined by subtracting from the total amount of nutrients eaten the amount eliminated.