Old shelterbelts or parts of them dot the Alberta landscape, a reminder of previous houses, farms and homesteads.
Shelterbelts were put in place to protect yards from the prevailing winds. Belts of trees planted on the north and west sides offer protection from the winter winds while east and southern trees one are used to defer hot summer ones.
Shelterbelts are an investment of plant material and time. But when properly placed, they pay off with lower heating bills and less snow to move.
They also offer privacy, screening the yard from the neighbours and people who pass by.
Like all landscaping, shelterbelts should start with a plan. Everything in the plan needs to have a reason for existing. Shelterbelts need to be planted where they will be beneficial and attractive.
Agriculture and Agri-Food Canada recommends that for shelterbelts to be effective, they should be planted perpendicular to the direction that the wind blows, at approximately 30 metres (100 feet) up wind from buildings or the area to be protected.
In Central Alberta, it is common to see shelterbelts on the west and north sides of farm yards.
Effects of mature shelterbelts on wind can be seen by the distribution of snow on windy days. Wind blowing from the west will initially drop snow in the first row of the shelterbelt (shrubs), then move over the rest of the belt, dropping more snow on the east side. The remaining wind and snow will remain well above most buildings slowly arching to the ground about 105 metres (345 feet) from the last row of trees.
Ideally, a shelterbelt should contain five rows of plants. The first row on the windy side is usually shrubs, then comes two rows of deciduous trees, followed by two of rows of evergreens.
Using recommended distances between rows and making allowances for land on each side of the belt, expect to put aside at least 30 metres (100 feet) of land.
For many, putting this amount of land into a shelterbelt is not possible.
However, having a narrower belt will still defer enough wind to make it worthwhile.
It is better to reduce the number of rows as opposed to placing the rows closer together.
Plants that are placed too close together compete for nutrients, water and sunlight, resulting in all plants growing slower, thinner and more susceptible to disease.
The government no longer provides shelterbelt material. But there are a number of private suppliers with varying prices and different varieties of plant material.
It pays to shop around and to join with others as the cost per tree decreases with volume.
Do some research — books, Internet or look around the neighbourhood —to find out what plants are most likely to thrive in your location.
Once the planning is completed, the land needs to be worked and kept weed free for a year before being planted. Once planted, the seedlings need to be watered regularly and the area kept free of weeds until the plants are established.
An alternative is to use a planter that will plant seedlings and put down a weed barrier at the same time. Check with the local county to see if they rent the machines or know who does.
Plants that die should be replaced to keep the belt uniform, reducing the chance of a wind tunnel developing.
As the plants grow, simple pruning to correct damage or poor growth habits is recommended.
Be prepared to remove trees if they become too crowded, are growing too close together or at the end of their lifespan.
The following are government sites that will give more specific information on shelterbelts:
http://www.agr.gc.ca/eng/science-and-innovation/agricultural-practices/agroforestry/shelterbelt-planning-and-establishment/?id=1344636433852
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex981
Linda Tomlinson is a local horticulturalist who can be reached at your_garden@hotmail.com.