Shade Trees for the Northeast 



elm disease and also are frequently af- 

 fected by the elm leaf beetle. 



The English elm (Ulmus procerd) 

 is a large tree, sometimes reaching 100 

 feet in height. It has a straight trunk 

 that extends into the tree crown, and 

 branches that spread or ascend to form 

 an oblong, rounded crown more like 

 the oaks than the American elm. The 

 leaves, 2 to 3 inches long, remain on 

 the tree later in the autumn than those 

 of the American elm. The English elm 

 can be transplanted quite easily and is 

 adaptable to the same types of soils 

 as the American elm. It has the tend- 

 ency to produce numerous shoots or 

 suckers from the roots. 



For that reason, another European 

 species, the Scotch or Wych elm, which 

 is similar to the English elm in form 

 and growth habit but does not produce 

 suckers, has often been preferred, both 

 for lawn and street planting. The 

 leaves of the Scotch elm are about 3 

 to 6 inches long. Several horticultural 

 varieties of both these species are in 

 cultivation. 



The Chinese elm ( Ulmus parvifolia) 

 has small leaves, which turn bright yel- 

 low in the autumn before they fall. Its 

 flowers are formed in August or Sep- 

 tember. It is easily transplanted and 

 grows rapidly. It is hardy in south- 

 ern parts of the region. The Morris 

 Arboretum in Philadelphia has a beau- 

 tiful, large specimen of this tree. 



The Siberian elm is resistant to the 

 Dutch elm disease, but it is subject to 

 canker and leaf diseases. It is not rec- 

 ommended except for locations where 

 better trees will not grow or for places 

 where quick effects are wanted while 

 the more durable species are getting 

 started. It lives 25 to 40 years. 



THE OAKS are hardy and long-lived, 

 and have beautiful foliage in summer 

 and autumn. Some of the species that 

 are native to the Northeast are well 

 adapted for use as shade trees on lawns 

 and along streets. 



In southern Wisconsin, northern 

 Illinois, and northeastern Iowa, and 

 down the Mississippi River to St. 



Louis, oak wilt threatens the red and 

 black oaks particularly. The disease 

 is spreading, and no control is now 

 known for it. The red and black oaks 

 therefore should not be planted as 

 street trees in the infected area at 

 present, and the home owner should 

 realize that he runs a risk in planting 

 them. In areas near the infected zone 

 it would be prudent to use red and 

 black oaks cautiously until more is 

 known about the disease. 



Pin oak in this region usually reaches 

 40 to 80 feet in height at maturity. It 

 makes a satisfactory shade tree in 

 southern Maine, eastern Massachu- 

 setts, Rhode Island, Connecticut, cen- 

 tral and western New York, central 

 Pennsylvania, and southward. The 

 straight trunk extends into the crown. 

 Its numerous slender branches, long, 

 horizontal or ascending above, shorter 

 and drooping below, form a broadly 

 pyramidal head. The branches bear 

 many short, upright, and pinlike twigs. 

 The leaves are 4 to 6 inches long, deep- 

 ly cut with five to seven bristle-tipped 

 lobes, and are thin, firm, dark green, 

 and glossy. They turn dark red in the 

 autumn and sometimes remain on the 

 trees during the winter. The pin oak 

 blooms in May when the leaves are 

 about one-third grown. It is particu- 

 larly adapted for use as a shade tree, 

 even on city streets, because of its 

 narrow symmetrical form, the ease of 

 transplanting, and rapidity of growth. 

 It is tolerant of a wide range of soil 

 conditions and of city smoke. Prun- 

 ing the lower drooping branches is 

 necessary, particularly for trees planted 

 along streets. 



Pin oak is subject to a leaf yellow- 

 ing chlorosis if alkaline soil condi- 

 tions prevent the trees from obtaining 

 sufficient iron, but the injured trees 

 will usually respond to soil treatment, 

 injections, or sprays. The fungus dis- 

 eases common to many species of oak, 

 such as the cankers and wood rots, may 

 occur on pin oaks, but otherwise the 

 species is free from serious diseases. 



The northern red oak is among the 

 largest of the northeastern oaks. It 



