Shade Trees for the North Pacific Area 



mands on soil fertility and moisture, 

 so that water and fertilizer must be 

 generously applied if a good lawn is to 

 be maintained. Sweetgum is an excel- 

 lent street and yard tree. It has attrac- 

 tive form and brilliant fall color. 



THE YELLOW-POPLAR, or tuliptree, 

 is narrowly pyramidal to broadly 

 spreading and grows rapidly to 100 to 

 160 feet. It is long-lived and fairly re- 

 sistant to cold, but it is intolerant of 

 drought and city smoke. It is rela- 

 tively free from pests. The yellow 

 flowers, about 2 inches in diameter, 

 beautiful but not showy, appear in early 

 June. The leaves are keystone-shaped 

 and turn yellow in the fall. The tree 

 requires moist, fertile soil and has a 

 tendency to rob lawns of moisture and 

 nutrients. This handsome tree unfor- 

 tunately is not well suited to most city 

 locations and is generally undesirable 

 as a street tree. It is recommended for 

 use on larger suburban and country 

 properties for shade and ornament. 



THE NORTHERN RED OAK is broadly 

 round-topped. Its growth is moder- 

 ately rapid, and it may attain a height 

 of 60 to 90 feet. It is moderately long- 

 lived. The shade is of medium density. 

 It resists cold but not drought and is 

 susceptible to root rot. The leaves turn 

 dark red or orange to brown in early 

 fall. It requires considerable space and 

 fertile soil for good development. This 

 oak has proved to be an excellent street 

 tree in the Eastern States and should 

 be equally satisfactory in the Pacific 

 Northwest. If given enough water, the 

 northern red oak may prove to be a 

 valuable shade tree in many localities 

 east of the Cascade Range. 



THE OREGON WHITE OAK grows 

 slowly but is very long-lived. Its ma- 

 ture height is 60 to 80 feet. This tree is 

 broadly round-topped and its shade is 

 rather sparse to moderately dense. Old 

 trees frequently are infected with mis- 

 tletoe and sometimes with wood rots. 

 It requires moderate moisture and soil 

 fertility for good growth, but does not 



compete seriously with lawns. It adds 

 neither grace nor brilliant color to the 

 landscape, but those lacks are far out- 

 weighed by its restful form and air of 

 tranquil permanence. Notwithstand- 

 ing its slow growth, this fine native 

 should be more extensively used as a 

 yard tree on lots of medium and large 

 size and as a street tree where space is 

 available for its development. 



THE PIN OAK may be pyramidal to 

 rounded and irregular, and 50 to 80 

 feet high at maturity. Its growth is 

 moderately rapid and it is moderately 

 long-lived. Its shade is of medium den- 

 sity. It is fairly resistant to cold but is 

 not resistant to drought. The leaves 

 appear in late spring, turn deep scarlet 

 in late fall, and often remain on the 

 twigs during most of the winter, par- 

 ticularly on young trees. It prefers rich 

 and moderately moist soil, and is more 

 easily transplanted than either north- 

 ern red oak or the Oregon white oak. It 

 does well in city environments and 

 can be used to advantage along streets. 



THE BIGLEAF MAPLE is broadly and 

 compactly round-topped. Its mature 

 height is 60 to 80 feet. Growth is rapid. 

 It is moderately long-lived. Shade is 

 dense. It is susceptible to a wilt disease 

 and often is attacked by insects, which 

 cause "honey-dew" to drip from the 

 leaves. It makes heavy demands on soil 

 fertility and moisture, so that mainte- 

 nance of a lawn under it is difficult. A 

 disease of unknown cause that affects 

 the leaves and kills the twigs has been 

 observed recently in parts of Califor- 

 nia. This handsome native has been 

 widely used, and even more widely 

 misused, west of the Cascade Range. 

 It is not a desirable street tree because 

 its roots heave sidewalks badly and its 

 dense growth necessitates frequent and 

 drastic pruning by line-clearing crews. 

 It has also proved unsatisfactory in 

 most city yards because of its space 

 requirements, litter, and its injurious 

 effect on lawns. These failures have 

 more or less obscured the suitability of 

 bigleaf maple for planting along rural 



