66 
Abies concolor, lives here in good condition for many years but is a 
less valuable tree in this climate than the plants of the same species 
derived from Colorado. Abies nobilis can live here in sheltered posi- 
tions but does not become a tree, although the beautiful Abies amabilis 
which grows with it on the mountains of Oregon and Washington does 
better but grows slowly and has now been in good condition in the 
Arboretum for several years. Another tree which is rarely seen in 
northern collections, Libocedrus decurrens, the Incense Cedar of Cali- 
fornia, is in good condition in the small collection of exotic conifers 
near the top of Hemlock Hill in an exceedingly sheltered position. The 
Incense Cedar is a tree of narrow columnar habit with bright green 
foliage, and in California sometimes grows to the height of one hun- 
dred and fifty feet and forms a massive trunk. There are good spec- 
imens in the District of Columbia and it may well be more generally 
planted in the middle and southern states. The two beautiful White 
Cedars of the northwest coast, Chamaecyparis Lawsoniana and C. 
nootlcatensis, can just be kept alive in the Arboretum where they drag 
out a miserable existence. Jeffrey’s Pine, Pinus ponderosa, var. 
Jeffreyi , lives but that is all that can be said of it. None of the other 
coast conifers of western North America are hardy here, but fortu- 
nately a few of the northern species range inland to the western slope 
of the northern Rocky Mountains, and when plants of these species 
are obtained from the interior cold region they can be successfully 
grown in Massachusetts. Thus the Arboretum is able to keep in good 
condition the so-called Red Cedar of the northwest, Thuya plicata, or 
as it is more often called, T. gigantea. This is one of the noblest 
trees of which North America can boast and, although it will never 
grow to its largest size or become an important timber tree here, it 
it is an ornamental tree in the Arboretum of considerable value and 
another witness to the importance of raising trees for cold climates 
from seeds gathered in the coldest parts of the area such trees natur- 
ally inhabit. It is possible, too, to grow here in the Arboretum the 
White Fir of the northwest coast, Abies grandis, and the coast Hem- 
lock, Tsuga heterophylla, raised from seeds gathered on the Rocky 
Mountains of Idaho as these two trees also range far inland. 
Colorado Conifers. The Douglas Spruce, Pseudotsuga mucronata, 
from Colorado is hardy in this climate and promises to be long-lived 
here although this tree from the northwest coast, where it grows in 
its greatest perfection, is not hardy in New England. The other con- 
ifers from the interior of the continent are hardy but are not of much 
promise as ornamental or timber trees for the eastern states. Picea 
pungens, the well known Colorado Blue Spruce, which is still largely 
propagated and sold by European and American nurserymen, will dis- 
appoint many planters of trees for its beauty is comparatively short- 
lived. This tree growing naturally in small groves by some of the 
streams of the southern Rocky Mountains becomes at the end of a 
few years thin and scrawny in habit with a few short branches on the 
upper part of the trunk, and is as ugly an object as a tree can well be. 
In cultivation the Blue Spruce for several years is compact in habit with 
wide-spreading branches in regular layers, but as the trees grow older 
