270 Plant Biology 



color of their drooping fruit or flower clusters, (2) their smooth twigs 

 and leaves, and (3) the even edges of the leaflets. The application of a 

 concentrated solution of sugar-of-lead in 60 per cent alcohol every few 

 hours is useful in poison-ivy and poison-sumac poisoning. Instead, a 

 strong solution of baking soda (sodium bicarbonate) may be applied as 

 soon after exposure as possible. Parsnip and carrot roots and herbs 

 affect certain persons much in the same manner as described above. 

 Some persons are poisoned when preparing them for eating. Certain 

 of our common orchids, known as yellow lady slipper (Cypripedium 

 parviflorum) and showy lady slipper (Cypripedium hirsutum) of the 

 orchid family produce symptoms similar to those described above because 

 of a fixed oil similar to cardol. 



QUESTIONS AND TOPICS 



1. What is meant by an economically important plant? 



2. In which phylum are the plants of greatest economic importance? Give 

 proof to justify your conclusions. 



3. List the various ways in which a knowledge of economically important plants 

 may be of value. 



4. Can you think of any plants which might be improved? What methods would 

 you suggest for such improvements? 



5. Define bacteria. Why are they classed as plants? 



6. How many species of bacteria are fairly well known? What percentage of the 

 total is in one way or another detrimental to man? How many are beneficial 

 to man? 



7. List the more common diseases of ( 1 ) man, (2) animals, and (3) plants which 

 are caused by bacteria, giving the causal organism for each disease. 



8. Write an article on the so-called galls of plants, including the causes and 

 economic importance. 



9. Give the values of a knowledge of plants in such professions as ( 1 ) medicine, 

 (2) dentistry, (3) horticulture, (4) agriculture, (5) landscaping, (6) forestry, 



■ 



(7) pharmacy, (8) business, and (9) everyday living by nonprofessional 

 people. 



10. Write an article on antibiotics, including the specific organism from which 

 each is derived, and including their uses in the prev^ention and treatment of 

 certain diseases. 



11. List some important diseases produced by (1) yeasts and (2) fungi, giving 

 the causal agent for each disease. 



SELECTED REFERENCES 



Bessey: Textbook of Mycology, The Blakiston Co. 



Brown, Panshin, and Forsaith: Textbook of Wood Technology, McGraw-Hill 



Book Co., Inc. 

 Dorrance: Green Cargoes, Doubleday, Doran & Co., Inc. 



