FOREST AND RANGE RESOURCES OF UTAH 



43 



Chokecherry usually causes some loss if stock are forced to live on 

 it alone, or if they have not had any of the plant for some time and 

 then suddenly eat large quantities of it. Infrequently stock are 

 poisoned by eating small quantities of it, as, under certain condi- 

 tions, it seems to develop the deadly prussic acid. The chief loss 

 from chokecherry occurs among sheep. Properly grazed, choke- 

 cherry causes no loss and is a valuable forage. 



There are a few other poisonous plants occurring in Utah, but 

 they cause such proportionately small losses that they need not be 

 discussed. 



KEEPING STOCK OFF POISON AREAS 



If the poison plant occurs on comparatively small areas, the stock 

 may be kept off by fencing or herding; if the plant lasts for only 

 a short time, as is the case with death camas, or is dangerous for 

 only a certain period, as is the case with lupine, stock may be kept 

 off entirely during the danger period. Another method for prevent- 



FlGURE 



-Sheep grazing on sneezeweed (Helenium hoopesii). Typical sneezeweed 

 on overgrazed ranges 



ing loss is to have the plant grazed by a kind of stock immune to 

 its poisonous properties; as, for example, grazing sheep upon lark- 

 spur. It happens in many places, however, that poisonous plants 

 are so widespread that considerable forage is lost if stock must be 

 kept off the area. In some cases it is not practical to graze the area 

 by a kind of stock immune to poisonous properties. In other cases 

 no stock is immune. 



ERADICATION OF POISONOUS PLANTS 



Studies have been made by the Forest Service of the best methods, 

 the cost, and the practicability of eradicating larkspur. Some re- 

 sults of this study are given in Farmers' Bulletin 826 (1). 



For National Forest ranges as a whole the most effective way of eliminating 

 loss from larkspur poisoning is to grub out the plants. This method is made 

 practicable by the fact that larkspur grows mainly in isolated patches. * * * 

 Grubbing, furthermore, appears to offer a permanent solution of the problem. 



