606 DISEASES OF CATTLE, SHEEP, GOATS, ETC. 



feeding conditions. The practice of trailing sheep to market renders 

 it necessary to urge sheep forward at a rate of from 6 to 10 miles 

 per day. It is easy to understand that under such circumstances the 

 sheep are forced to grab at any green thing within reach, and can not 

 exercise the same choice of forage which they would if feeding at 

 ease. The same conditions prevail in driving sheep from winter to 

 summer range and often with disastrous consequences. 



An obvious method for avoiding the danger from driving or 

 trailing sheep too rapidly consists in detailing two herders with each 

 band, so that one may travel in advance of the sheep and direct the 

 band away from the poisonous areas. The herder in the rear of the 

 band may cooperate w r ith the herder ahead in preventing the sheep 

 from becoming too closely crowded together. 



The present practice of the sheep raisers on Western ranges is to 

 keep sheep under the constant care of a herder, in bands of from 

 2,000 to 2,500. They understand the great differences in the skill 

 with which bands of sheep are managed by different herders. If a 

 band is frequently dogged and urged forward, the inevitable result is 

 to crowd the sheep together and render it impossible for those which 

 happen to be in the center of the band to feed. It is impossible to 

 insist too strongly upon the desirability of interfering as little as pos- 

 sible with the sheep during feeding. All sheep raisers understand 

 that it requires considerable time for a large band to become scat- 

 tered out after having been rounded up by dogs or by their fright. 

 The time necessary for such redistribution of the band is lost from 

 the feeding time and the sheep become hungry and excited. Under 

 such circumstances it is frequently observed that they are more apt 

 to eat unwholesome plants than when given greater liberty in feeding. 



The problem of stock losses from poisonous plants is affected also 

 by the water supply on the range. On ranges where the only water 

 supply in the dry season is found in alkaline lakes, it would seem de- 

 sirable to build troughs into which spring water is piped. This 

 would enable stock to obtain water more conveniently, and the water 

 would be less alkaline than when allowed to flow into alkaline lakes 

 and gradually become saturated with alkali by evaporation. 



It has long been observed that poisoning is especially apt to oc- 

 cur after heavy rains. A number of explanations for this fact have 

 been offered. It has been supposed that certain plants are more poi- 

 sonous when wet with fresh rains or dew than when dry. The ex- 

 planation which is most frequently suggested, however, is that after 

 heavy rain-storms the roots of various plants are more easily pulled 

 up than when dry, and it is well known that in the case of many 

 poisonous plants the active principle is chiefly located in the roots. 

 In the case of death camas, the writer attempted to determine the 

 question whether the bulb could ever be pulled up by the stem, and 

 found that under ordinary circumstances this could not be done. 

 After an unusually heavy rainstorm, however, it was found that a 

 considerable proportion of the bulbs could be drawn out of the soil by 

 pulling upon the stem of the plant. This observation is of some im- 

 portance in connection with the fact that the bulb of death camas is 



