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Yearbook^ of Agriculture 1949 



They give off a disagreeable, pungent 

 odor when they are crushed. 



The growth rate of white spruce is 

 much slower in dry locations than in 

 moist, well-drained soil. Its life span in 

 the forest is 200 to 300 years. 



It is slightly susceptible to the Orien- 

 tal spruce fungus disease, but usually 

 is not seriously injured. 



Black Hills white spruce is compact 

 and slow in growth, and is generally 

 useful in the northern Lake States. 



The common Douglas-fir is a large, 

 pyramidal specimen, with branches 

 growing well down to the ground. 



MANY OTHER kinds of trees, both 

 deciduous and evergreen, might have 

 been mentioned here. This list tends to 

 be conservative; it is based on the ex- 

 perience of many men who plant and 

 take care of trees. But we compiled it 

 with the thought that it could be a 

 springboard from which you might 

 take a deep plunge into the fascinat- 

 ing hobby of planting and growing 

 shade trees around your home or de- 



velop an interest in the trees of your 

 city streets and parks. 



ALMA M. WATERMAN is a forest and 

 shade-tree pathologist in the Bureau 

 of Plant Industry, Soils, and Agricul- 

 tural Engineering. She is stationed in 

 New Haven, Conn., where she has 

 studied trees and their diseases for 

 more than 25 years. Dr. Waterman is 

 a graduate of Brown University. 



R. U. SWINGLE is a forest pathologist 

 and is in charge of the field head- 

 quarters of the Division of Forest Path- 

 ology in Columbus, Ohio. He is at 

 present investigating phloem necrosis, 

 an epidemic virus disease of American 

 elm. Mr. Swingle is a graduate of Ohio 

 State University. 



CLAYTON S. MOSES, a graduate of 

 Pennsylvania State College, is a forest 

 pathologist in the Bureau of Plant In- 

 dustry, Soils, and Agricultural Engi- 

 neering and is stationed in Madison, 

 Wis. In recent years he has investigated 

 the epidemic dying of oak in Wisconsin 

 and adjoining States. 



SHADE TREES FOR THE SOUTHEAST 



RALPH M. LINDGREN, R. P. TRUE, E. RICHARD TOOLE 



Residents of the Southeastern States 

 have a wide choice of trees for shade 

 and ornamental purposes. They also 

 have a difficulty in making their selec- 

 tion, for their section has variables in 

 climate and altitude and other con- 

 ditions that do affect tree growth. 

 (Florida alone, for example, can be 

 subdivided into at least three distinct 

 zones in which climate and commonly 

 used plants are likely to differ a good 

 deal from each other.) 



Furthermore, certain local conditions 

 may sometimes prevent the successful 

 use of a species within the recognized 

 geographic range of the Southeast. For 

 these reasons, the list of trees we pre- 

 sent is not expected to be entirely 

 acceptable throughout the region or 

 adequate for specific localities. 



THE LIVE OAK, a tree of history and 

 beauty, is long-lived and rather slow 

 growing. It attains tremendous size 

 with age. It branches low into mas- 

 sive and widespreading limbs, and 

 forms a broad, dense, round-topped 

 crown of dark, glossy, evergreen leaves. 

 It resists storm damage, insects, and 

 diseases; the costs of care and mainte- 

 nance therefore are relatively low. 



Propagation from seed or transplants 

 is not difficult. The live oak is used 

 widely where enough space is avail- 

 able on lawns and along driveways and 

 roads. Severe freezes injure it, but it 

 is considered satisfactory in such in- 

 land cities as Shreveport. 



SOUTHERN MAGNOLIA, with its beau- 

 tiful flowers and evergreen foliage, is 



