How much is a good shelterbelt worth?
A lot, if you consider how much it would cost to have one put in.
Blair English, an agroforestry specialist at AAFC Brandon, was once told by a rural homeowner how much a contractor had quoted her on the cost of putting in a row of six-to eight-foot spruce trees with a tree spade to protect her property from icy winds.
“She had a quote for $50,000,” he said, during a presentation on the hows and whys of shelterbelts at Sprucewoods Community Centre last week sponsored by the Agri-Environment Services Branch, formerly known as the PFRA.
“A nice shelterbelt makes a property very attractive for resale. It’s functional and beautiful,” he said.
The research farm at Indian Head has been providing applicants with free trees since 1901, giving seedlings of various kinds, from bushy, snow-retaining shrubs such as caragana and willow, wildlife food species like sea-buckthorn and chokecherry, to tall hybrid poplars and hardy bur oak. Last year, some 6,000 people took delivery of four million trees.
The other benefits from having a sheltered yard add up to real dollars, including reduced heating bills.
This claim was proven in the mid-1980s by researchers who compared the heating costs of two trailers, one sheltered and one parked on the bald prairie. Keeping the sheltered trailer at a comfortable temperature cost 25 to 30 per cent less, he said.
Before zero-till farming, field shelterbelts were planted to keep the topsoil from blowing away. Now, many grain farmers are finding that despite their snow-trapping advantages, the rows of shrubbery aren’t compatible with 60-foot seeders and have removed them.
Many shelterbelts were also lost due to spray drift, especially green ash, which can’t tolerate glyphosate-based herbicides.
“That just turfed them,” he said. “Once the high-clearance sprayers came in, that took them out. A lot guys just figure it’s easier without trees in the way.”
On the other hand, caragana is naturally resistant to Roundup, and is a good choice for blocking spray drift. It is used by many people to protect their gardens.
Many organic farmers are putting in field shelterbelts in order to provide habitat for wildlife such as birds and insects that control pests. Studies have shown a yield boost with some crops where trees were used to provide more diverse food sources for pollinating bees.
“If you make the landscape uniform with no diversity, you’re losing out on things you don’t even realize,” he said. “Birds, for one, and pollinators like bees.”
English predicted that field shelterbelts will be making a comeback over the next decade, as people start recognizing the benefits of biomass fuel and firewood production, carbon sequestration, and moisture retention in the dry Prairie climate.
“Zero till still isn’t bulletproof. If you had consecutive years of drought or crop failure and you don’t have the stubble, the soil will be left to the elements,” he said. “We are somewhat vulnerable, I think.”
Reports that the green ash borer has arrived as far north as Minnesota could mean that in the coming years, the disease more devastating than Dutch elm could arrive.
Once it infects a tree, the green ash borer can kill it within a year.
For that reason, shelterbelt owners may want to consider replacements such as basswood, or increasing the diversity of their plantings so that their hard work doesn’t end up going down the drain.
He knows of at least one potato farmer who tore some trees out near his home and found out the hard way just how much he was benefiting from it.
“His wife or someone left the door open or it didn’t shut, and they had soil drifting right into their new house,” he said. “We can’t have trees everywhere. We still have to produce food. But I think we have to find a balance.” [email protected]