THE NATIONAL NURSERYMAN 
23 
Notes from Arnold Arboretum 
Dwarf Conifers. Of the many cone-bearing trees 
there are abnormal dwarf forms, and a few conifers are 
naturally dwarf shrubs. The former are of different 
origin; most of them are seedlings, some have grown 
from buds on branches of large trees, and others have 
been produced by exposure to excessive cold and high 
winds, and these when transferred to more favorable 
surroundings often lose their dwarf habit. A good ex¬ 
ample of a dwarf of the last class is the depauperate 
Larch which grows at the timber line on Mt. Fugi in 
Japan. Seedlings of this little plant raised in the Ar¬ 
boretum twenty-live years ago are now nearly of the 
same size as the seedlings of the trees of the Japanese 
valleys raised at the same time. In the sandy sw amps 
of Prince Edward Island Black Spruces not more than 
two feet high produce cones and fertile seeds, and near 
the timber line of the White Mountains it is jiossihle to 
w^alk on dwarf mats of the Balsam Fir wdiich lower 
down on these mountains is a tall tree. Transferred to 
better soil where the winter climate is less severe these 
alpine and boreal dwarfs would soon assume the tree 
habit of the species. Dwarfs of some species, however, 
which evidently owe their habit to environment, retain 
the dwarf habit w hen transferred to more favorable sur¬ 
roundings. Such dwarfs are some of the forms of the 
European Piniis montana from high altitudes and some 
dwarf forms of Junipers which reiuoduce the dwarf 
fonn in their seedlings. Seedling dwarfs have been pro¬ 
duced by many different species, hut they are naturally 
most numerous in species w hich have been largely raised 
in nurseries where seedlings are carefully watched and 
abnormal forms are preseiwed. It is not surprising 
therefore, that trees like the eastern Arbor Vitae and the 
Norway Spruce have produced many such forms in nur¬ 
series as few other cone-bearing trees have been so 
largely raised from seed. 
It is only in recent years that dwarf conifers have at¬ 
tracted much attention, for Loudon in his “Arboretum et 
Fruticetum Botanicum” published in 1838 enumerates 
only ten. These are two dw arf forms of Pinus montami, 
two forms of the Norway Spruce, a dwarf Cedar of Le¬ 
banon, a dwarf Bed' Cedar {Jimiperus virginiana), a 
prostrate form of Juniperus salnna, and twu) dwarf forms 
of Juniperus communis. He knew" no dw arf Arbor Vitae, 
Chamaecyparis, Hemlock, or dw"arf form of Abies. 
Beissner in the second edition of his “Handhuch der Na- 
delholzkunde,” published in 1899, enumerates one hun¬ 
dred and four dwarf conifers in thirty-one species; of 
these tw^enty-live are forms of the Norway Spruce, 
eight are forms of Law"son’s Cypress {Chamaecypafis 
Lawsoniana), and eight are forms of the Arbor Vitae of 
the eastern United States. In addition to the plants en¬ 
umerated by Beissner there are a few which originated 
in this country and wdiich do not appear to have been 
known to him. 
There is a good but by no means a complete collection 
of dwarf conifers in the Arboretum, for it is difficult to 
keep track of the new forms which appear in the nur¬ 
series where large numbers of conifers are raised from 
seed and are often given names without descriptions, and 
some dwarfs like those of Lawson’s Cypress and the 
Chinese Arbor Vitae are not hardy here. The Arboretum 
collection is much visited, however, by nurserymen for 
there is now" a demand for these plants, wdiich have 
their uses in small gardens and are less happily planted 
in making low banks of foliage about the base of sub¬ 
urban cottages. 
Perhaps the handsomest of the dwarf conifers in the 
Arboretum collection is a form of the Japanese Pinus 
densiflora (var. umbraeulifera). This is a wide, vase¬ 
shaped plant w hich in Japanese gardens is often ten feet 
high and broader than high. The leaves are of a bright 
cheerful green and comparatively small plants flow"er 
and produce minute cones. Among the fourteen or fif¬ 
teen dw"arf forms of the Norway Spruce none is hand¬ 
somer than one of the varieties described by Louden in 
1839 (var. Clanbrasiliana). This is a low", very compact, 
round-topped bush which rarely grow"s more than three 
feet high but spreads to a diameter much greater than 
its height. The plant is said to have originated on the 
Moira estate near Belfast, Ireland, tow ard the end of the 
eighteenth century and to have been carried to England 
by Lord Clanbrasil for w"hom it was named. Equally 
good is the variety nana w hich has a flatter top and does 
not grow as tall as the Clanbrasiliana but spreads into a 
broad bush. The subglobose var. Gregoriana and the 
variety prostrata are interesting plants. Some of the 
dwarf Norway Spruces, especially the variety Ellwan- 
geriana, have a tendency at the end of a few" years to 
form a vigorous leading shoot and eventually to become 
arborescent. 
Two dwarfs originated in the Arboretum in 1874 
among seedlings of Picea pungens, the Colorado Blue 
Spruce and Abies lasiocarpa. The original plant of the 
former is now seven feet high and ten or twelve feet in 
diameter, and has so far escajied the loss of branches 
which disfigures this Spruce after it is thirty years old. 
Although well worth the attention of lovers of dw"arf 
conifers, Pinus pungens compacta is little known be¬ 
yond the limits of the Arboretum. The seedling of Abies 
tasiocarpa retained its dw"arf habit for many years but 
has now" begun to grow" more vigorously and to assume 
the typical habit of the species. The dw"arf of the Euro- 
jiean Silver Fir {Abies Picea compacta) behaves here in 
the same way and after a few" years grow s out of its 
dw arf habit. There is in the collection a small plant of a 
dwarf of Abies concolor which is very compact, but it is 
