Eco-buffers provide all the benefits of conventional shelter-belts with greater ecological paybacks. They supply better wildlife habitat, enhanced wild bee and beneficial insect refuge, and their compact design makes them a good fit for the small farm, says Laura Poppy, agroforestry specialist at the Agroforestry Development Centre at Indian Head, Saskatchewan.
What are eco-buffers?
“An eco-buffer is a linear row of trees and shrubs, planted in a natural arrangement, composed of a variety of species native to the eco-region. The goal is to create this concentrated group of trees and shrubs so they will establish very quickly, and capture the site more quickly than the conventional design.”
An eco-buffer may have as many as 20 varieties of trees and shrubs, with a minimum of four to five being shrub species. It includes both fast-growing or nurse trees and slow growing trees, plus trees with different characteristics such as thorns, suckering, fruit production and varying flowering periods. Every sixth plant is a long-lived tree. Thirty percent of the plants in the buffer, are trees, 70 per cent are shrubs. Species choice depends on the region and what grows naturally in the area.
While trees in a conventional shelter belt are planted as much as 3.5 metres apart in rows up to six metres apart, in eco-buffers rows are 2.5 metres apart, plants one metre apart, within the rows.
Research at AAFC Agroforestry Development Centre at Indian Head, found that trees and shrubs were not negatively impacted by concentrated plantings; traditional shelterbelt design had a higher density of weeds than eco-buffers; and eco-buffers resulted in quick site capture eliminating the need for long term-weed control.
Although an eco-buffer can contain up to five rows of trees, on a small farm it could also work with two or three.
Shelterbelts, whether conventional or eco-buffers, increase the attractiveness of a field or farmstead while sequestering carbon and improving air quality. And, they more than pay for themselves in energy savings and increased crop yields.
“Trees re-direct the wind,” says Poppy. “They take the energy out of it and snow drops, adding moisture to the soil. In summer there’s less evapotranspiration. That increases yields. Also, by reducing wind there’s less damage to crops, especially high-value, sensitive crops such as melons and corn.”
Trees create a micro-climate, a good place for plants and a good place for pollinators and beneficial insects. Birds that prey on insect pests will also live there. Eco-buffers on an organic farm in Alberta have attracted families of tree swallows that devour the insects that pester cattle.
“We are promoting this new planting design (eco-buffers) across Canada in partnership with other agencies and groups,” says Poppy. “So if someone wanted to utilize this new design for their windbreak/shelterbelt/woody buffer, they should contact their local ag or conservation group representative to see about incentives and technical help. They can also contact our AAFC Agroforestry Development Centre for more information. We will put them in contact with the right people and provide a copy of the factsheet/details if needed.”
For more information, at www.agr.gc.ca, type “eco-buffer” into the search box.
Editor’s note: this article originally ran in “Small Farm Canada.” It is reprinted here with permission. †