QUESTIONS 249 



3. Define poison. 



4. (a) What families embrace the most poisonous plants? (b) Name the 

 six genera of plants which cause the heaviest hvestock losses. 



5. (a) To what extent are poisonous plants generally palatable? (b) Dis- 

 cuss the relation of range use and variation in poisonous-plant substances. 



6. Discuss salt and salting of livestock as factors in poisonous-plant control. 



7. (a) To what extent and under what conditions is eradication of poisonous 

 plants practicable? (b) What methods of plant eradication have been tried, 

 and which have given the best results? Why? (c) What is the cost of plant 

 eradication if one of the more effective methods is employed? 



8. Discuss the handling of stock on depleted driveways where poisonous 

 plants occur. 



9. What methods of herding and bedding sheep in relation to plant poison- 

 ing are most effective and desirable? 



Note. — The bibliography for the general subject of stock-poisoning 

 plants is placed at the end of Chapter XIV (page 289). 



