THE NATTONAT. NURSERYMAN 
Notes From Arnold Arboretum 
Prostrate Junipers. Tliis general name is given to a 
number of low-growing .lunipers with wide-spreading 
branebes lying close to the ground and loiniing broad 
mats. For covering banks, the margins of ponds or 
beds of larger conifers they are useful and are mueb 
used in some parts of the country, although there is still 
a great deal of confusion in commercial nurseries about 
the identity and correct names of lh(‘se .lunipers. 
The prostrate Red Cedar. This is perhaps the hand¬ 
somest of all these plants. On exposed parts of the 
wind-swept cliffs near Oguiujuit and at Kennebunkjiort, 
Maine, this Juniper grows only about two feet high, with 
branches extending ovei' a diameter of eighteen or twenty 
feet, their ends lying Hat on the ground. At Kennebunk- . 
port, in a position not fully exposed to the wind, one of 
these plants has formed a short stem about two feet high 
from the summit of which start branches spreading hori¬ 
zontally and foraiing a broad head. Whether the dwarf 
habit of these Junipers is due to the exposed position 
where they grow or not cannot be determined until plants 
are raised from seeds produced by them, for it is possible 
such seedlings may assume the ordinaiy upright habit of 
this tree. The fact that such prostrate plants sometimes 
occur at a distance from the coast, as in Lexington, 
Massachusetts, indicates perhaps that the prostrate form 
has become fixed, as it is in the case of prostrate forms of 
some other Junipers. Dwarf forms of Jiiniperus vir- 
giniana are described in German books on trees under 
the name of Jimiperus virglniana repens or J. virginiana 
horizontalis, but the Arboretum has no information about 
these plants and it is impossible to determine if they are 
similar to the prostrate plants of the Maine coast which 
possibly are still without a name. In this country the 
prostrate Jiiniperus virginiana is not known in cultiva¬ 
tion, and in this Arboretum there are only a few small 
grafted plants of the tall-stemmed specimen at Kenne- 
bunkport. This Juniper well deseiwes the attention of 
the lovers of hardy conifers. 
JuNiPERus COMMUNIS, VAR. DEPRESSA. Tliis is a dwai’f 
form of the common Juniper and forms broad masses of 
stems ascending from a prostrate base and covered with 
linear, sharp-pointed, dark blue-green leaves marked on 
the upper surface by broad white bands. This dwarf 
Juniper is very common in the northeastern states on dry 
gravelly hills and in old pastures, sometimes almost en¬ 
tirely occupying the ground to the exclusion of other 
plants. In nurseries this plant is sometimes called 
Jiiniperus canadensis or /. nana canadensis. The erect- 
growing form, which is more eommon in Europe than in 
the United States, very rarely occurs in New England 
and sometimes grows on the lower slopes of the Appa¬ 
lachian Mountains as far south as North Carolina. On 
the hills in the neighborhood of the Delaware Water Gap 
in Pennsylvania this upright form seems more abundant 
than in other parts of the country and to be the {irevailing 
Juniper. Erect forms of J. communis, known in gar¬ 
dens as the Swedish or Irish Junipers are often planted in 
the middle states but are not veiy satisfactory in Massa¬ 
chusetts. . There is a form of the variety depressa (var. 
aurea) with yellow-tipped hranches which has Ixam a 
popular garden plant in the United Stati's for several 
years. The variety monlana is tlui dwaidest of the pros¬ 
trate forms of J. communis, randy grow ing mon‘ than 
twm feet high and forming dense mats of prostrati' stems. 
From variety depressa it may also Ixi distinguished by its 
shorter and broader incurved leaves. This litth' plant 
grow s on the Atlantic coast from Maine to Newfoundland, 
on the Rocky Mountains, in Alaska, and through noithern 
Asia and Eurojic. It is sometimes called Jiiniperus 
nana, J. al])ina and ,/. sihirica. On the high mountains 
of Japan there is a form of J. communis (var. nipponica^ 
with wide-spreading and ascending or ofbm prostrate 
stems w hich is similar to the variety monlana. Nothing 
is known of the value of this Japanese variety in gardens 
here as it does not ajipear to have been introduced until 
Wilson sent seeds to the i\rboretum two years ago from 
wdiich only a single plant has yet appeared. 
JuNiPERus HORIZONTALIS. This is one of the handsom¬ 
est of the prostrate Junipers and an excellent garden 
plant. It has procumbent and prostrate stems which 
often develop roots and sometimes extend over hroad 
areas. The leaves are scale-like, acute, blue-green or 
steel-blue, and the fruits are bright blue and ripen at the 
end of the second season. This is a wddely distrihuted 
plant from the coast of Maine to Rristish Columbia, rang¬ 
ing south to Massachusetts, w^estern New" York, Illinois 
and Montana. It grow s on sea cliffs, gravelly slopes, or 
in western New York in deep, often inundated swamps. 
For many years, until it was found to be distinct from the 
European Juniper, this plant w"as known as Jiiniperus 
Sabina var. procumbens. It has also been called ,/. pros¬ 
trata and J. regions. There is a form of this Juniper 
(var. Douglasii) with steel blue foliage, turning purple 
in the autumn, w hich grow s on the sand dunes of Lake 
Michigan and is known in gardens as the Waukegan 
Prostrate Juniper. There are large beds of J. horiz-on- 
talis in the general Juniper Collection. 
JuNiPERus PROCUMBENS. This is the best know n of the 
prostrate Junipers wdiich Japan has sent to the gardens 
of the west. It is a plant with wide-spreading proeum- 
bent stems, blue-green, sharply pointed leaves marked 
on the upper surface hy twm white lines. The fruit is 
not known. This Juniper finds a place in nearly every 
Japanese garden, but it must be a rare and probably local 
plant in its distribution, as a wudd plant was not seen by 
Wilson during his extended travels in Japan. It is said 
to have been introduced into Great Britain before the 
middle of the last century bul w"as soon lost from 
European gardens until it was reintroduced in 1893. 
This Juniper is largely used as a garden plant in Cali¬ 
fornia w^here it is imported from Japan, and less com¬ 
monly in the eastern states. It is perfectly hardy and 
well established in the Arboretum, and can be seen with 
the other Junipers. This Japanese Juniper is closely 
related to the prostrate Juniper of w-estern China and the 
Himalaya J. sqiiamata, a plant with aw 1-shaped, sharply 
