Fabulous Firs

Even if you’re not a gardener, you may know the fir tree from the popular balsam firs sold as cut trees over the holidays.  This tree and other related fir trees make beautiful landscape plants, providing a habitat for birds as well.

The firs (Abies) are in the Pine family and are called conifers since they produce cones similar to pine trees.  Since firs often come from mountaintops, they prefer cooler climates as in the north.  They tend to be somewhat slow growing, but over time make stately trees.  They are not for urban settings as they can be injured by air pollution.

You can tell firs from spruces usually by squeezing the needles.  Those of firs are soft to the touch, while spruce needles are sharp-pointed and will prick.

Firs have easy culture.  Give them full sun for best growth, and a moist but well-drained soil, preferably an acidic one.  Try to avoid clay soils. Diseases to watch for include rusts and root rots, the latter if soils stay too wet.  Pests to watch for include the woolly adelgid and bark beetles that may disfigure the tree but not seriously harm it.

The balsam fir (balsamea) with its rich green leaves prefers cold climates, being hardy to USDA zone 3 (-30 to –40 degrees F). It will tolerate some shade and wet soils.  It is native in much of eastern North America, especially the higher elevations.  Although this tree might eventually reach 75 feet high and 25 feet wide, over 10 years you might expect 10 feet high and six feet wide from planting a foot high seedling.  This fir has very fragrant needles you can buy in sachets, or collect when fallen from holiday trees to make your own winter potpourri.

You often can find seedlings for sale in spring from conservation districts in bundles, useful for wildlife habitats.  I have some for this purpose, as well as for providing a backdrop in the landscape for flowers, and for some shade.  As they grow, I thin them out each holiday for cut trees.    You also may find the ‘Nana’ or dwarf cultivar in nurseries.  This only reaches about two feet high and three feet wide, so is good in rock gardens and along building foundations.

The white fir (concolor) also makes a great cut tree for holidays, having a pyramidal shape that it retains even as a mature tree.  It will eventually reach 30 to 50 feet high, and 20 to 30 feet wide.   Similarly hardy to the balsam fir it, however, is native to mountainsides of western North America and has waxy, bluish-green leaves.  It is one of the most adaptable firs thriving in northern zones from east to west, and under various conditions including some drought, salt, and pollution.

The Fraser fir (fraseri) is similar to the Balsam fir, but without fragrant needles.  Its shiny green needles have silvery undersides.  Native to the Appalachian Mountains, it withstands heat better than the Balsam and some other firs.  It, too, is a popular holiday tree and tends to hold its needles well when cut.

The Korean fir (koreana) is a much smaller tree, only reaching about 15 to 20 feet high, and half as wide.  It is one of the least hardy firs, listed as hardy to only USDA zone 4 or more often 5 (-10 to –20 degrees F).  It has broad, dark-green needles with white bands underneath.  Because of its compact growth, it gives a dense appearance.

The Caucasian fir (nordmanniana) is a stately tree when mature, growing 40 to 60 feet high and with dark green needles.  Native to the Caucasus as its name indicates, it has intermediate hardiness to the other firs of USDA zone 4 (-20 to –30 degrees F).  There is golden-leaved yellow cultivar called ‘Golden Spreader’ that only grows to about three feet high and five feet wide.

The Veitch fir (veitchii) is perhaps the least commonly seen of the firs, but makes an excellent ornamental tree for cold zone 3 climates.  Native to central and southern Japan, it has dark green needles that are white underneath. With time it can reach 50 to 75 feet high, and half as wide.

Consider adding firs to your landscape, if room, to provide an evergreen backdrop for flowers, a windbreak, a visual screen, a habitat and winter protection for birds, or singly as beautiful specimen trees.

Dr. Leonard Perry, Horticulture Professor Emeritus
University of Vermont
12/1/16

Distribution of this release is made possible by University of Vermont and Green Works—the Vermont Nursery and Landscape Association.