Dwarf Conifers Collection

With over 150 specimens, the Dwarf Conifer Collection displays the variation of form and colour of dwarf coniferous trees.

What is a Conifer?

The word "conifer" is derived from the Latin word meaning "cone-bearing". Trees in this group include the well known pines, spruces and larches. However, some conifers such as yews and junipers, produce a berry-like fruit instead of a cone. Most conifers have needle-shaped or scale-shaped leaves and most are evergreen, keeping their leaves throughout the winter.

What is a Dwarf Conifer?

A dwarf conifer has slow growth and does not reach the normal size of a wild conifer of the same species. Most have less than 15 cm of growth each year and at 15 years old would reach a maximum height of 1.8 m.

Some dwarf conifers, such as bristle-cone pine and Canada yew, are naturally small-statured wild species. Most, however, are natural mutations that have been selected by horticulturalists. Many are derived from a condition called a "witch's broom": a bud mutation that causes very compact growth, making the plant look as if its foliage has been squished together. Horticulturalists grow them from cuttings or by grafting. This allows the selection to grow with the same characteristics found on the original plant.

Dwarf conifers show a wide range of colours. They are at their brightest in June (new growth) and in September (mature foliage). Some terminology used to describe the many different forms include:

Globose Round in general shape
Pendulous Branches droop or "weep"
Columnar Much taller than broad
Prostrate Ground-hugging or "carpeting"
Ovate Egg-shaped, broader at base

The Dwarf Conifer Collection

A walk through the collection may help you decide which dwarf conifers would look good framing a doorway, accenting a garden corner or enhancing a rock garden. Some grow quite large and could define a property boundary line. None of the plants in this collection are clipped or formed; what you see is natural growth.

The classification of dwarf conifers in this collection is done by genus. The first name of the two-word latin name (ex. Pinus in Pinus strobus) is called the genus name and it denotes a group of closely related dwarf conifers (in this case, pines).

See below for a description of how to use the labels at the base of each plant.

Map of the Dwarf Conifer Collection
Abies - The Silver Firs

The only member of this group native to Ontario is the balsam fir (Abies balsamea). The form displayed here, hudsonia, is a natural alpine plant that grows on the slopes of the White Mountains in New Hampshire.

Chamaecyparis - The False Cypresses

We have selections from two Japanese species represented here. The Japanese false cypress (Chamaecyparis obtusa) selection 'NANA' has dark green foliage that is packed in fan-shaped tiers. The Sawara false cypresses (C. pisifera) include the yellowish 'SULPHUREA'. 'FILIFERA NANA' has a thread-like foliage.

Juniperus - The Junipers

Junipers come in many sizes, colours, forms and textures. Note the contrast between the low, thin-foliaged blue creeping juniper (Juniperus horizontalis 'GLAUCA') and the tall, pyramidal Mayer juniper (J. communis 'MAYERI'). The Chinese juniper (J. chinensis) selection 'PFITZER' has slow growth but can still reach a considerable size.

Larix - The Larches

This is an exception to the evergreen rule. This conifer drops all of its needles every fall and grows new ones in the spring. Note the dwarfs from the tamarack (Larix laricina) which were grown from cuttings taken from witch's brooms found in Nova Scotia. The other dwarf here is a beautiful spreading form of the European larch (L. decidua 'PENDULA').

Microbiota

The only species of this genus is a prostrate conifer from Siberia, Microbiota decussata.

Picea - The Spruces

Nest spruce (Picea abies 'NIDIFORMIS') is one of many selections of Norway spruce and it is a good example of a dwarf conifer derived from a witch's broom. Note how the dwarf Colorado spruces (P. pungens) still have the bluish needles of the common front yard tree.

Pinus - The Pines

This group includes the species which is the oldest known living organism, the bristle-cone pine (Pinus aristata). Some individuals of this pine species in California are over 5000 years old. Different pine species selections in this area show some very interesting shapes. The Austrian pine (P. nigra) selection 'PYGMEA' creates a compact pincushion effect. The eastern white pine (P. strobus) selection 'NANA' can be pruned to look like miniatures of the trees in paintings by Group of Seven artist F.H. Varley.

Platycladus - The Oriental Arborvitae

The Oriental arborvitae (Platycladus orientalis) is the only species in this genus and is native to Korea and China.

Psuedotsuga - The Douglas Fir

The Douglas fir (Pseudotsuga menziesii) can grow over 90 m in its tree form. 'PUMILA', however, is a dwarf selection that may only grow 1.3 m in 25 years.

Taxus - The Yews

These dwarf conifers are very hardy and can withstand extreme climates. Canada yew (Taxus canadensis) is a low spreading shrub that is native to eastern Canada. The Japanese yew (Taxus cuspida) includes the selection 'AURESCENS' which is vibrantly yellow. Many examples of Japanese yew hybrids (T. x media and T. x hunnewelliana) show their distinct growth characteristics.

Thuja - The Arborvitae

Selections of eastern white cedar (Thuja occidentalis) fill three beds to represent the arborvitae in this collection. There are miniature forms such as 'HETZ MIDGET', golden forms such as 'GOLDEN GLOBE' and pyramidal forms such as 'SMARAGD'. 'FILIFORMIS' is very interesting with its thread-like branches. Ontario's oldest living trees are eastern white cedars growing along the Niagara Escarpment. Some individuals are over 1000 years old. Korean cedar (T. koraiensis) is represented in the dwarf conifer collection as well. It is located in a different bed than the eastern white cedars (see map).

Thujopsis - The Broadleaved Arborvitae

Thujopsis dolabrata is a native of Japan. 'NANA' is hardy and has showy white bands on the undersides of the leaves.

Tsuga - The Hemlocks

The eastern hemlock (Tsuga canadensis) is a fairly common tree throughout most of southern Ontario. 'PENDULA' produces branches that fail to straighten resulting in layered masses of foliage.

A label at the base of each plant displays the following information.

-White Pine Selections- (1)
Pinus strobus (2) 
'NANA' (3)

Pine Family (4) 
Pinaceae
(1) Class - This shows the common name of the conifer (this dwarf conifer is a selection of the white pine).

(2) Botanical Name - This is the Latin name of the conifer (genus name is Pinus, species name is strobus).

(3) Selection Name - When a new dwarf conifer is discovered or propogated, it is given its own selection name. 'NANA' is often used because it is the Latin name for dwarf.

(4) Plant Family - This indicates the common family name (e.g. Pine Family) and the botanical family name (e.g. Pinaceae).

NOTE: Wild species of dwarf conifers will have labels that state the plant's nativity (e.g. w. U.S.A.) and, if there is one, a common English name (e.g. bristle-cone pine).

Donors to this collection are listed in the Hales-McKay Memorial Shelter located near The Arboretum Centre.

Interested in making a donation to the dwarf conifer collection? Please contact the Arboretum Director at 519-824-4120 ext. 52356.