In Quebec, as elsewhere, natural hedgerows were torn down a few decades ago to allow for the expansion of agricultural land and to facilitate the movement of large machinery. Unfortunately, this practice has had all sorts of indirect consequences: wind erosion, of course, but also the spread of farm odors and pesticides and the loss of habitat for birds and pollinators.
Fortunately, for more than 30 years, a few pioneers within the Quebec Ministry of Agriculture, Fisheries and Food have been fighting to demonstrate the benefits of windbreaks in agriculture: soil and water conservation, better yields, protection of animals, buildings and greenhouses, better ecological balance and secondary yields such as fruit or wood production.
It is thanks to the advice of a Ministry agronomist (Yvon Pesant, now retired) that I planted a windbreak on the 3.5 acres of land I had just acquired in the Eastern Townships in the early 2000s.
Choice of Plants
I learned that for an optimal windbreak, it is strongly recommended to plant several rows of trees and shrubs. Also, planting a variety of species creates a more natural look than lining up cedars or other conifers. I wanted a quick result, but at the same time, we had to preserve our magnificent view of the Appalachians!
With the help of my husband, I planted two rows of fast-growing trees (silver maples, larches, spruces and pines) and a row of shrubs (serviceberry, viburnum and elderberry) that will not grow more than 3 to 5 m tall at maturity. These shrubs produce small fruits that attract different species of birds throughout the year. If I had it to do over again, I would plant 2 rows of shrubs and only one row of trees because after 20 years we have cut down almost all of the trees which grow really fast. But they gave us wood for heating or carpentry and Christmas trees.
Preparation of the Soil and Planting
Before starting the planting, we had the existing meadow tilled three meters wide before planting our 350 small plants. Rather than going to a garden center, it is possible to find them at a very good price at a forestry producer. But since the shoots were barely 10 centimeters long, they had to be protected for the first three to five years to avoid competition from herbaceous vegetation.
On a small surface, one can use natural mulch, but given the large surface and following the recommendations of the Institute of Agri-Food Technology of Quebec (ITAQ), located in La Pocatière, we planted our plants through a thick black plastic sheet. Without it, the goldenrod would have quickly reduced our efforts to nothing. We also tried a geotextile fabric on a small area, but it proved to be more expensive, less effective and extremely difficult to remove after five years because the weed rootlets were so intertwined in the fabric.
So, after plowing, we unrolled the plastic film and secured it with stones and metal anchors. Then we drilled holes through the film, just enough to accommodate the soil core of the small plants. These should be closer together in a windbreak than when planting decorative specimens. Trees should be spaced about two meters apart if a single row is planted, but three meters apart if two or three rows are planted.
During the first year, care had to be taken to ensure that the young trees did not run out of water. After that, they took care of themselves. We had very few losses. The deer stayed away thanks to the dog from the neighboring farm. Even the field mice didn’t give us any trouble. Some of our friends did have to put up a protective fence around their young hardwood tree shoots.
Growth and Protective Effects
After three years, we started to remove the plastic mulch from some of the sloping areas where erosion was occurring under the fabric. After 5 years, we removed it everywhere. Taking advantage of the maintenance of the hydro-electric lines near our home, we were able to recover RCW (ramial chipped wood) at no cost, which we then spread around the plants once the plastic was removed. The effect has been very beneficial.
It is fascinating to see the evolution of the windbreak each year and to see the benefits to counter our wind problem. Our vegetable garden was completely sheltered from the wind after 5-10 years. Also, our land has become much more private and we are better protected from dust and road noise. Our windbreak produces more oxygen than the existing grassland and absorbs greenhouse gases. According to the ITAQ of La Pocatière, a windbreak can absorb up to 300 tons of CO2 in 40 years per km of hedge.
The fruits of our shrubs are a real treat for the birds and for us. And finally, the trees planted along our driveway (perpendicular to the prevailing winds) reduce snow accumulation on the road.
Of course, after 10-15 years, we started cutting down maples and larches, which can grow up to two meters per year, to make room for the mature shrubs. But what a great supply of ramial wood!
This article is adapted from the author’s book: Guide du jardinage écologique, Éditions Broquet, 2013.
Excellent article. I used to live in the UK where they still have many hedgerows and it is habitat for wildlife among other good things.