The leaves of Juniperus
horizontalis are very small and sharp-pointed. Many
of the leaves are in the range of 1.5 - 3 mm long, scale-like
and tightly appressed to the stem. There are always some
leaves of this type present. On some plants there may also
be longer, spreading awl-shaped leaves to 10 mm long, though
most are less than 7 mm in the material I have seen in Wisconsin.
As in all Junipers the mature female
cones are blue, often glaucus, berry-like structures.
The growth form is very distinctive
in that the branches creep laterally along the ground, spreading
horizontally, as the Latin name suggests, with only the
short terminal branches
sweeping upward. This is in strong contrast to the erect,
tightly columnar shape of J. virginiana, whose leaves
are very similar to those of J. horizontalis.
The range of Juniperus horizontalis
lies mostly in Canada. It is represented in the U.S.A. primarily
in widely scattered outliers from the main population. In
Wisconsin this species is mostly restricted to the sandy
shores of Lake Michigan and to a few very sandy areas near
the Wisconsin and Mississippi Rivers.