20 BULLETIN 816, U. S. DEPARTMENT OF AGRICULTURE. 
laurel oaks, evergreen magnolia, camphor, rubber, silk oak, or grevillea, and casua- 
‘rina. Eucalypti are planted to some extent in Florida, but the climate is such that 
only on the drier grounds of the interior are they likely to succeed, and even there 
they are not to be compared with other excellent species of trees that may be culti- 
vated successfully. 
TREES FOR SPECIAL PURPOSES. — 
In the heart of a city, where the greatest difficulty is experienced 
in getting trees to grow, the ailanthus will probably thrive when 
nearly all other kinds fail. The sycamore and the London plane 
are also good for such places. The Carolina poplar will frequently 
srow under these conditions, and its use may sometimes be 
warranted. 
For very narrow streets the Lombardy poplar is the best tree. 
(Fig. 14.) Trees suitable for use within the reach of ocean spray or 
on sandy lands near the coast are the red oak and the red or scarlet 
maple south to Charleston, S. C., while the sweet gum and the live 
oak are equally good from Norfolk southward and along the Gult of 
Mexico. The red oak, sweet gum, red maple, and eastern live oak 
are all grown suieueee tlie along the Pacific Ocean, while the Cali- 
fornia live oak can be used from San Francisco southward. The trees 
that endure the most alkali appear to be the bladder-nut tree,’ 
London plane, peppermint gum,? blue gum,* the Washingtonia and 
other hardy fan palms, Canary Island date palm, the camphor 
tree, and Acacia cyclops and Acacia retinodes. Only the first two 
withstand severe freezing weather. The red oak and the red maple 
are worth testing for these conditions. 
DESCRIPTIONS OF STREET TREES. 
ATACIA. 
The acacias, or wattles, are a large group mostly of small trees 
with showy yellow flowers. Although much used in California, many 
of them are too small to make satisfactory shade trees, and because 
of shallow rooting they are injurious to sidewalks. They also stump- 
sprout badly. They thrive in regions 2 and 3 and in restricted 
portions of regions 1 and 5. 
The Australian blackwood,‘ blackwood acacia, or wattle, is a 
strong, upright tree, growing to a height of 75 feet and forming a 
well-shaped head. It is badly affected by citrus scale, and on this 
account its planting is sometimes prohibited. 
The black wattle® is a strong-growing round-headed tree that 
reaches a height of 40 feet and has dark-green leaves. 
The green wattle® is a rapid-growing tree, reaching a height of 
60 feet and forming a round head with finely cut leaves. 
1 Koelreuteria paniculata. 4 Acacia melanorylon R. Br. 
2 Eucalyptus amygdalina Labill. 5 Acacia decurrens mollis Lindl. 
3 Eucalyptus amygdalina angustifolia. 6 Acacia decurrens Willd. 
