230 PLANT SOCIETIES 



388. Some Details of Plant Societies. — Societies may be 

 composed of scattered and intermingled plants, or of dense 

 clumps or groups of plants. Dense clumps or groups are 

 usually made up of one kind of plant, and they are then called 

 colonies. Colonies of most plants are transient: after a short 

 time other plants gain a foothold amongst them, and an 

 intermingled society is the outcome. Marked exceptions to 

 this are grass colonies and forest colonies, in which one kind 

 of plant may hold its own for years and centuries. 



The return to forest. Bushes and trees now begin to crowd. 



389. In a large newly cleared area, plants usually first 

 establish themselves in dense colonies. Note the great patches 

 of nettles, jewel-weeds, smart-weeds, clot-burs, and others in 

 recently cleared but neglected swales, also the fire-weeds 

 in recently burned areas, the rank weeds in the neglected 

 garden, and the ragweeds and May-weeds along the recently 

 worked highway. The competition amongst themselves 

 and with their neighbors finally breaks up the colonies, and 

 a mixed and intermingled flora is generally the result. 



390. In many parts of the world the general tendency 

 of neglected areas is to run into forest. A large number of 

 different plants begin growth in a cleared area. Here and 

 there bushes gain a foothold. Young trees come up: in time 



