38 BULLETIlvr 800, TJ. S. DEPARTMENT OF AGRICULTURE. 



On the basis of tlie same theory. Sheep 372 and Sheep 461 were 

 treated with eserin and pilocarpin. In both cases the eserin produced 

 defecation. Sheep 372 recovered, while Sheep 461, which received a 

 somewhat larger dosage, died. It is evident that the results from the 

 use of arecolin and eserin were somewhat doubtful. "Wliile it seems 

 probable that the course of the illness was somewhat modified, these 

 drugs can hardly be considered as effective remedies. 



From the character of the lesions in the central nervous system it 

 seems probable that no remedy would be very effectual, and that lit- 

 tle reliance should be placed on any kind of treatment. Possibly if a 

 line of symptomatic treatment were followed with the same care with 

 which a human patient is treated, the course of the illness might be 

 modified, but such treatment is impracticable, and in any case a fatal 

 result is to be expected in most animals. 



ERADICATION OF THE WHORLED MILKWEED. 



The apparent rapid increase of this weed in some sections, together 

 with the fact that it is dangerous in hay as well as while green, makes 

 the question of its eradication an exceedingly important one. 



From what has been said of the habits of the plant, it is evident 

 that its eradication will be a very difficult matter, for the young seed- 

 ling, once started in a favorable location, begins to spread by adventi- 

 tious buds from roots, being greatly aided by cultivation where cover 

 crops are not grown. The rapid spread of the plant is aided by ordi- 

 nary cultivation. The more the plant is broken, the better it thrives. 

 Disk harrowing and plowing, without removal of the roots, simply 

 helps to propagate the plant. 



If the roots are exposed on the surface they will die, but every 

 piece left in the ground become^ the possible origin of a new plant, 

 and the greater the number of pieces, the larger will be the resulting 

 crop. Plate IV, figure 2, shows a plant growing from a piece of 

 root one-quarter of an inch long. 



Presumably if tilled crops like beets, potatoes, and corn are grown, 

 intensive cultivation by destroying the aerial parts of the plant will 

 eventually have some effect, but it is a discouraging piece of work. 



Cutting or mowing the milkweed before seeding, while it does not 

 eliminate the plant, will accomplish much in preventing its distribu- 

 tion. This is especially important in driveways where hungry ani- 

 mals are trailed, and in locations like bedding grounds, where animals 

 are herded close together. Had this been done in the " death patch " 

 near Cortez, previously referred to, the losses would have been greatly 

 reduced, if not entirely avoided. 



Prevention of seeding of the whorled milkweed will stop the spread 

 of the plant to a considerable extent. Mowing milkweed and de- 



