The Shade Trees oe Denver. 
9 
planted as a street tree and for wind breaks and hedges. It is readily 
distinguished from the common black locust by its smoother bark, the pres¬ 
ence of large branched spines on the trunk and branches, and by its leaves, 
which are twice compound. The pods also differ from those of the black 
locust, being much larger and having a twisted shape. A thornless variety 
of the honey locust occurs which is especially desirable where the presence 
of spines is objectionable. 
The form of this tree is quite variable, being rather broad and low 
in open situations, but running up pretty well when grown among other 
trees. It is a graceful tree, the small leaflets closely arranged, giving its 
foliage an unusually delicate appearance especially when contrasted with 
that of other trees. 
The honey locust, while not quite hardy in the northern parts of 
Colorado, is capable of making a good growth in most sections of the state 
and is capable of enduring considerable drouth. The wood is hard and 
strong besides being very durable, moreover it is not subject to the attacks 
of borers, so often destructive to the black locust. 
This tree is readily grown from seeds which should be collected in 
the fall and kept dry until spring. The seeds are so hard that they are 
not apt to germinate the first season unless they are first scalded with hot 
water just previous to planting. This treatment, if sufficiently thorough, 
causes them to swell, after which they should be planted at once in a well 
prepared seed bed. The seedlings should receive some protection during 
the first winter by either heavy mulching or laying down. 
BLACK LOCUST, YELLOW LOCUST. 
(Robinia pseudctcacia L.) 
The common locust possesses many of the most desirable qualities as 
a utility tree for the state of Colorado, since it is readily propagated by 
seeds and root cuttings, is a rapid grower, resists drought well and is hardy. 
The wood, moreover, is hard, heavy, of good fuel value and resists decay 
to a remarkable degree. In thick plantations this tree makes a single 
trunk of slender growth, suitable for fence and telephone posts and may in 
time reach a sufficient size to furnish material for railroad ties. 
This locust is also much grown as a shade and ornamental tree. Its 
foliage possesses a delicate texture due to the small size of its leaflets 
and when in bloom the tree presents a very attractive appearance and gives 
off a most delicious fragrance. When grown in open places the trunk does 
not often run up far before dividing several times, in which respect it 
resembles the elm. The smaller branches are beset with stiff 
prickers which occur in pairs at the base of each leaf stalk, thus making it 
an unpleasant subject to handle, but, like the honey locust, smooth forms 
also occur. This tree frequently sprouts, especially when the roots are in¬ 
jured in any way, and when cut the stump sends up strong shoots. 
The most serious drawback to the growing of the b!ack locust 
in the Eastern States is the fact that this tree is especially subject to the 
attacks of borers which, while they do not at once kill the tree, yet cause 
great injury to it. Moreover the wood is so perforated by these pests 
that the trunk is often rendered practically worthless. While these enemies 
of the locust have not yet appeared to trouble this tree in places where 
it is now growing in this state, it is possible that in time they may be 
found, especially if the tree becomes common. But before this does occur 
it is probable that locust plantations may be grown to sufficient size to make 
them paying investments. 
The tree is usually grown from seeds, which should be treated the 
same as those of the honey locust. 
SUGAR MAPLE. HARD MAPLE. 
(Acer Saccharum Marsh.) 
It is doubtful if any tree is held in greater esteem than the sugar 
maple by those who are familiar with the tree as it occurs in the hard wood 
