22 BULLETIN 575, U. S. DEPARTMENT OF AGRICULTURE. 



at all unusual for the hungry animals to grab hastily at the plants, 

 and this may result in disastrous consequences. Under such circum- 

 stances it is important that the cattle shall not be driven rapidly, 

 for then they will snatch all the* more, and they should also have 

 been thoroughly fed before going upon such a drive. 



This has been illustrated in certain places in Colorado, where it is 

 customary to drive cattle from one range to another, and for years 

 there were always heavy losses. In the old days it was the custom 

 to gather the cattle together and rush them as rapidly as possible 

 through the place where the tall larkspur was growing. Losses 

 invariably occurred. In recent years, instead of gathering the cattle 

 together they have been put through the drive in small numbers 

 and have been allowed to feed before starting. They are not driven 

 rapidly. Under such conditions no losses have occurred. 



It is also evident, from what has been said earlier in this paper, 

 that if cattle can be kept off fields of larkspur until after the plant 

 has blossomed, little trouble may be expected. This method has 

 been employed for many years in certain regions in Colorado, where 

 it is a common practice to "ride for poison," as it is called; that is, 

 the herders ride and keep the cattle down from the higher ranges 

 until the larkspur has blossomed and matured, after which there is 

 no further danger. The same thing has been accomplished in cer- 

 tain regions by putting up drift fences which are designed to keep 

 the cattle on the lower ranges until the danger is past. There are 

 valleys known as death traps fftr cattle. Frequently it will be found 

 that in these valleys the tall larkspur is thriving in large clumps, and 

 cattle drifting in will feed freely upon it. It is often possible under 

 such conditions to clear out this larkspur, or enough of it so there 

 will be no danger. In order to kill the plants, the roots of most of 

 the species should be cut off at least 6 or 8 inches below the surface. 



Deaths from Cicuta poisoning rarely occur except in the case of 

 animals that are almost in a starving condition. If very hungry 

 animals are turned loose upon a range, and they find a number of 

 Cicuta roots lying beside a ditch or along a mountain stream, and 

 there is nothing else to eat, they eat these roots, of course, and 

 death follows. 



The fosses of sheep from death camas (Zygadenus) occur under 

 very similar conditions to those of cattle from larkspur. Zygadenus 

 grows very early in the spring. It precedes the grasses in its growth 

 and is present in a succulent condition at a time when other forage 

 is extremely scarce. Inasmuch as it occurs frequently in large 

 masses, if sheep are trailed over these places they are liable to get 

 enough to cause heavy losses. It is particularly important in the 

 handling of sheep in such localities that, if possible, they be grazed 

 in loose order. In fact, this applies to the handling of sheep under 

 all circumstances. When the animals are massed together they will 



