8^6 BULLETIlSr 790, U. S. DEPAETMENT OF AGRICULTURE. 



In some cases tlie total acreage and distribution of larkspur on a 

 cattle range unit is such that grubbing is not practicable because of 

 the cost, which, for the present at least, is excessive. Where this con- 

 dition occurs a combination of grubbing, fencing, and herding may 

 solve the problem. If it "will not, and the loss is unwarranted, a 

 change from cattle to sheep may be advisable. 



The larkspur plants should be grubbed by cutting the main roots 

 6 to 8 inches below the surface of the ground. Some plants may be 

 missed in the first grubbing, and others will grow from portions of 

 the roots left in the ground. These plants should be removed by 

 grubbing one year after the first work is done. 



The grubbing can be done best as soon as the plants have made 

 sufficient growth to be readily recognized. This varies with different 

 localities and with altitude. Usually the work may start about one 

 week after growth begins on the area in question. 



A mattock with the spur cut off and the blade drawn out to about 

 9 inches in length is recommended for grubbing in loam soils. For 

 rocky soils, a pick with one end flattened to 2 inches wide, or a com- 

 bination pick-mattock has proved satisfactory. 



The practical results from the grubbing work alread}^ done war- 

 rant every possible effort to determine the feasibility of grubbing out 

 the larkspur on every cattle range unit where it is definitely known 

 that cattle are killed annually by larkspur poisoning. The first step 

 is to determine the value of cattle poisoned annually ; the second step 

 is to determine the acreage of larkspur and the approximate cost of 

 eradication. In a great many cases grubbing will cost less than the 

 value of the cattle lost annually from larkspur poisoning. In some 

 cases it may be advisable to grub out the larkspur if the cost is as 

 great as the value of the cattle lost in eight years. 



Where fencing is the alternative, it should be remembered that 

 maintenance of fences in mountain country is expensive and that 

 if the fence is clown or a gate is left open during the dangerous 

 poison period the fence may fail to prevent loss. 



PARTIAL BIBLIOGRAPHY FOR STOCK-POISONING PLANTS OF 



THE UNITED STATES (ARRANGED CHRONOLOGICALLY). 



I. PUBLICATIONS OF THE UNITED STATES DEPARTMENT OF AGRICULTUKE. 



A. AVAILABLE FOR FREE DISTRIBUTION BY THE DEPAET5IEKT. 



Marsh, C. D., Clawson, A. B., and Marsli, H. Zvsadenus, or Death Camas. 



BuUetm 125, 1915. 

 Marsh, C. D. The Loco-weed Disease. Farmers' Bulletin 380, 1909 (reprinted 



without change in 1915). 

 Marsh, C. D. Prevention of Losses of Live Stock from Plant Poisoning. 



Farmers' Bulletin 720, 1916. 

 Marsh, C. D. The Cause of " Spewing Sickness " of Sheep. Bureau of Animal 



Industry leaflet A. 9, 1916. 



