be expected. It is very hardy in the Arboretum where it has been grow- 
ing for thirty years. The largest specimen in the collection will be found 
in the rear of the Laurels by the side of a walk along the northern base 
of Hemlock Hill. There are also a number of specimens in the mixed 
plantation of conifers near the corner of Centre and Walter Streets. 
All the conifers of the Rocky Mountains are hardy in the Arboretum. 
The most promising of them are the Douglas Spruce, Pseudotsuga mucro- 
nata, and the Engelmann Spruce, Picea Engelmannii. The Douglas 
Spruce is one of the great trees of the world; it grows to an enormous 
size; it produces valuable timber, the Oregon Pine of commerce, and it is 
widely distributed from the shore of the Pacific Ocean over nearly all the 
mountain ranges of the west as far east as Colorado. A valuable lesson 
has been learned from this tree. For individuals raised' from seeds gath- 
ered near the Pacific coast had not been hardy in New England, while 
plants from Colorado seed are perfectly hardy here, grow rapidly, and 
promise to become useful ornamental and timber trees. This experience 
with the Douglas Spruce shows in a striking manner the importance of a 
careful selection of the seeds of trees, and that in the case of widely dis- 
tributed trees, like many conifers, the seeds should be gathered from re- 
gions most similar in climate to the region where the trees raised from 
the seeds are to grow. Such careful selection of seeds has been too gen- 
erally neglected. When, however, its importance is understood it is pos- 
sible that the area over which many trees can be successfully cultivated 
will be greatly extended. 
Engelmann’s Spruce in Colorado forms pure forests up to altitudes of 
11,000 or 12,000 feet and ranges north into Alberta. It is a narrow 
pyramidal tree with gray-green foliage and cinnamon-red bark. It is too 
soon to speak of the value of this tree as a permanent addition to our 
plantations for it is only fifty years since it was discovered. The trees in 
the Pinetum of the Arboretum, which are believed to be the best in culti- 
vation, are thirty-two years old. The Colorado White Fir, Abies con- 
color , is a f ast-growing and hardy tree which of all the silver Firs appears 
to best suited to New England. There are a number of specimens in the 
Pinetum about thirty years old but, like other silver Firs, they will prob- 
ably grow less attractive as they grow older. The California form of 
Abies concolor, the Abies Lowiana of some collections, is hardy here but 
is a less desirable tree in this climate than the Colorado form. The best 
known of the Colorado conifers is the so-called Blue Spruce, the Picea 
pungens of most collections. This has been largely propagated in Euro- 
pean and American nurseries and very generally planted. As this tree 
grows in Colorado, where it is not common, it becomes long before it 
attains its full size thin, ragged and unsightly. In cultivation the young 
plants are handsome and symmetrical, but as the cultivated plants grow 
older they lose their lower branches and much of their beauty, and it is 
probable that this tree will not much longer retain its popularity. The 
Rocky Mountain form of the western Yellow Pine, Pinus ponder osa var. 
scopulorum, and the Rocky Mountain White Pine, Pinus Jlexilis , can be 
