ECOLOGY 235 



the places in which they grow, how they migrate or are 

 disseminated, means of collecting food, their times and sea- 

 sons of flowering, reproduction, and the like. 



Review. — What is a plant society? Why do plants grow in 

 societies? Name societies that are determined chiefly by moisture. 

 What societies are most abundant where you live? Name those de- 

 termined by latitude and altitude. Name some small or local societies. 

 What are colonies? Where are they most marked? Why do they 

 tend finally to break up? How are societies composed when colonies 

 are not present? How do forests arise on cleared areas? What effect 

 have pasturing and mowing? How do plants associate? What is 

 undergrowth and overgrowth? Explain how societies may differ at 

 different times of the year. What are zonal or belt societies? Discuss 

 autumn colors. What is ecology? 



Note. — One of the best of all subjects for school instruction in 

 botany is the study of plant societies. It adds definiteness and zest 

 to excursions. Let one excursion be confined to one or two societies. 

 Visit one day a swamp, another day a forest, another a pasture or 

 meadow, another a roadside, another a weedy field, another a cliff 

 or ravine. Visit shores whenever possible. Each pupil should be 

 assigned a bit of ground — say 10 or 20 feet square — for special study. 

 He should make a list showing (1) how many kinds of plants it con- 

 tains, (2) the relative abundance of each. The lists secured in different 

 regions should be compared. It does not matter if the pupil does not 

 know all the plants. He may count the kinds without knowing the 

 names. It is a good plan for the pupil to make a dried specimen of 

 each kind for reference. The pupil should endeavor to discover why the 

 plants grow as they do. Challenge every plant society. 



