478 



XELA TlOhr TO ENVIRONMENT. 



trees "f dilTereiit hei,ii;lils, the ranop)- is said to be "comjjound" 

 or "storied." Where it is uneven, there are open plaees in 

 the canopy which admit more light, in which case the under- 

 growth may be different. The interior of the forest lies between 

 the canopy and the floor. It provides for aeration of the floor 

 and interior occupants, and also room for the boles or tree trunks 





r .. 





Fit'. 48Q. 



Mature furest of redwood (Sequoia sempervirens). (Bureau 

 Dept. Agr., Bull. 3S.) 



of Forestry, U. S. 



(called by foresters the wood mass of the forest) which support 

 the canopy and provide the channels for communication and 

 food exchange between the lloor and canopv. Tlie canopy 

 manufactures the carbohydrate food and assimilates the mineral 

 and proteid substances absorbed In- the roots in the soil; anti 

 also gets rid of the sur])Ius water needed for conve}ing food 

 materials from the lloor to the place where thev are elaliorated. 

 It is the seat where energy is created for work, and also the 

 place for seed production. 



