152 REPRESENTATIVE PLANTS 



Type 2. TJie Spruces. Short-leaved Evergreens 



Where growing. Spruce trees are common evergreens in 

 cultivation, more especially the lUue and Norway. Two 

 otlier common species are the '' black " and " white " ; 

 these are the ordinary " Christmas trees " and are very 

 abundant natives of the northeastern United States. The 

 tree as it grows ought to be observed, if possible, — its 

 regularity of form and branching and the marked ar- 

 rangement of branches. Compare the form with that of a 

 pine. 



Sprays. Examine a spray of several years' growth. What 

 arrangement has the branches ? How can you tell the end 

 of a year's growth ? Examine the apical bud and the lateral 

 buds adjacent to it. How do these help you to explain the 

 branching arrangement and position ? How many "years' " 

 growths of the main stem are leaf bearing ? Below the 

 leaves observe the bark surface and the similarity to the 

 pines. 



Leaves. Examine the leaves. How are they borne on 

 the twigs, like the pines or otherwise ? What directions 

 with reference to the twig do they assume ? Observe the 

 number. Examine a leaf (???). What is its color, shape, 

 and size? How many surfaces has it? Examine (Ip) for 

 stomates and the nature of the margin and point (apex). 

 Examine a cross section (Ip) and, compare it with a similar 

 section of the pine. In what do they agree and in what do 

 they differ ? ^lake drawings showing spray, single leaf (?>i), 

 and cross section (Ip). 



Reproduction. The process of reproduction is similar 

 to that of the pine. If possible compare the cones of 

 the two types, observing points of resemblance and dif- 

 ference. 



Uses. Read about the uses of spruces in paper making. 

 What other uses have they ? What is " spruce gum " ? 



