Mugho pine, P. montana var. Mughus.‡
Usually more a bush than a tree (2 to 12 ft.), although it may attain a height of 20-30 ft.; mentioned under Shrubs.
Norway spruce, Picea excelsa.‡
The most commonly planted spruce; loses much of its peculiar beauty when thirty to fifty years of age; several dwarf and weeping forms.
White spruce, P. alba.*‡
One of the finest of the spruces; a more compact grower than the last, and not so coarse; grows slowly.
Oriental spruce, P. orientalis.
Especially valuable from its habit of holding its lowest limbs; grows slowly; needs some shelter.
Colorado blue spruce, P. pungens.*‡
In color the finest of the conifers; grows slowly; seedlings vary much in blueness.