Why I Plant Norway spruce

Posted: March 19, 2014

Are you thinking about planting a field to trees? Many folks want to plant hardwoods such as oak, walnut, and black cherry. They believe these will grow into valuable hardwoods; they are partly correct. The problem is getting them to grow.

By Gary Gilmore  PA DCNR Service Forester

For over ten years, I have been planting trees on my Tree Farm to reforest a hilltop strip mined and reclaimed in the 1980s. I have also worked on a DCNR program to plant trees on strip mine sites in Clarion and Jefferson counties. These experiences have taught me that planting a tree is easy; getting it to survive is a challenge. There are many factors that will frustrate your attempts to grow trees on a strip mine site (as well as in fields). These may include a thick cover of grass that smothers tree seedlings. The soil may be so thin that it quickly dries out, killing the seedling. Every seedling you plant is potentially food for the voles, moles, mice, rabbits, and deer. The soil is usually so compacted it is difficult for a tree to put down roots. I’ve planted oaks, maples, pine, larch, chestnut, locust, and spruce. The only tree among these that is doing well is Norway spruce. This is now my tree of choice for reforesting a field. Let me tell you a little more about why I like it.

Norway spruce is native to northern Europe but for the past 100 years it has been extensively planted across Pennsylvania. It is fast growing and can put on two feet of height growth each year. At maturity they can be 100 feet tall and have a life span of centuries. It is not invasive and rarely starts new seedlings near established plantings.

Norway spruce requires no site preparation. It is a shade tolerant conifer that can survive dense grass cover. In other words, this tree can compete with grass and eventually win. If the grass is controlled by mowing or herbiciding, Norway spruce will just grow faster. It may take several years for it to become established and get above the grass, but given time, it will.

Norway spruce is not readily eaten. Deer mostly leave it alone. Every white pine I ever planted was nipped; not the spruce. Voles and mice love thick grass and eat the bark off hardwoods at ground level, but for the most part, leave the spruce alone.

Norway spruce is tolerant of drought. Conifers, better than the large leaf hardwoods, have the ability to shut down during a dry period. This gives Norway spruce the ability to survive a summer drought that kills recently planted hardwoods. On the other hand, Norway spruce is tolerant of wet conditions. Plant it in wet spots and it does well.

Norway spruce has few insect pests. My red pine were defoliated by an infestation of pine saw fly this year. Hardwood leaves are munched on by slugs, a variety of caterpillars, and deer. The only pest on Norway spruce is a gall and white pine weevil. Damage from these pests is relatively minor. When white pine weevil does attack Norway spruce the damage is not as severe because spruce has lateral buds along the leader and on its branches, not just on the end of the branch as is the case with white pine. This means another branch will quickly take over. Where nearly every open grown white pine will be attacked by the weevil, many Norway spruce will not.

Norway spruce can tolerate and grow in a variety of soil conditions. It does well on fertile soil and survives on poor soils. Soil pH can vary from acidic to alkaline. It can grow on compacted soil and over time the roots will penetrate and loosen soil structure.

Norway spruce makes for a good cover crop to prepare the soil and make it easier to grow hardwood trees in the future. Norway spruce will shade out grass and invasive plants such as bush honeysuckle, autumn olive, and multiflora rose. The needles will create a duff layer and allow beneficial fungi to become established.

Norway spruce can pack on the carbon. As an evergreen, it is able to photosynthesize any time the sun is shining and the temperature is above freezing. This causes it to grow tall and large in diameter in a relatively short time. This may mean you could harvest wood products from the trees you planted. The wood is not as dense as hardwoods; however, it makes good construction lumber. Most of the studs you buy are made from one of the spruce species.

Norway spruce has some wildlife value. Red squirrels love to feast on its seeds and you often find mounds of cone scales where they feed. The merlin falcon and green heron prefer to nest in Norway spruce. The dense evergreen foliage provides a wind break in winter and a dense shade in the summer.

Norway spruce is easy to control. If you no longer want it growing on your land, just cut it down. It does not root sucker, stump sprout or store seed to pop up later. No need to apply herbicides. The only thing left is the stump and an extensive root system that slowly rots away while providing organic matter to the soil.

Norway spruce is so fast growing that within ten years it is large enough to bring in the house for a Christmas tree. This makes it a rather quick return on the planting investment. While not the most ideal Christmas tree because of the sharp pointed needles, neither is it a bad choice. The stiff branches hold all the ornaments and the tree will retain its needles as long as it is well watered.

Planting trees takes time and money. Weather, animals, or competing plants can easily frustrate your dreams. Norway spruce is the one tree I’ve found that is adaptable enough to endure most of these challenges and thrive with minimal site preparation and maintenance. By using Norway spruce to turn a field into an evergreen forest, I have found I can shade out the grass, displace or exclude invasive plants, and prepare the soil for the planting hardwoods as the spruce are cut and used.

While not everyone may share my fondness for Norway spruce, it is worth serious consideration for those of you who want to turn a field into a forest and get it done quickly.