388 CONIFERS 



SUMMARY 



The conifers belong to a class of the higher plants. 

 They have periods of active and less active growth, both 

 together resulting in the appearance of annual rings. 

 Because their seeds are not entirely inclosed in an ovary, 

 but lie uncovered on a scale, they are called gymno- 

 sperms. Conifers are of great economic importance, for 

 they supply much of our lumber, tar, pitch, and all our 

 turpentine and resin. Hardwood trees grow with the 

 evergreens. They belong to many families of flowering 

 plants and furnish lumber, fuel, and nuts. Forests help 

 to regulate the flow of streams and they prevent the 

 washing away of the soil. 



QUESTIONS 



How are gymnosperms like other plants ? How do they differ from 

 other plants ? What kind of a trunk is characteristic of gymnosperms ? 

 How does a tree which grows in a forest differ from one which grows 

 in an open field ? Why ? What are annual rings ? How are they 

 formed ? Describe the branches ; the leaves ; the roots ; the cones or 

 strobili ; the fruit. What is a sporophyte ? Name the gymnosperms. 

 Make a list of the uses to which lumber is put. What other products 

 come from the evergreen forests ? In what ways are forests beneficial ? 

 What are the governments doing to protect them ? What regions in 

 your own state are covered with forests ? 



REFERENCES 



Government pamphlets and bulletins. 

 Hough, American Woods. 

 Keeler, Handbook of Trees. 

 National Geographic Magazine. 

 Sargent, Trees of North America. 

 Schenck, Forest Policy. 



