Now that winter is upon us, it's a little late to be thinking about windbreaks, but better late than never. If you're finding all that's shielding you from Arctic gales is a few strands of barbed wire, think of windbreaks.
If your property is a city-sized lot, perhaps you should think of a fence to moderate the wind. I've seen too many solid fences in this area that have sections blown askew by strong winds to recommend a solid fence. Letting some wind through seems easier on the construction of a fence, and breaking the force of it will make a storm more tolerable.
Experts say that a windbreak that filters winds, not just stops them, is most effective. A solid windbreak, a solid fence or very dense planting throws the wind upward, but this curls back down beyond the windbreak, creating eddies that may be destructive. It may protect from the force of wind up to 10 times the height of the tallest part of the windbreak. The denser the windbreak planting, the faster the wind eddies beyond the windbreak.
I've heard some recommend planting Lombardy poplars in a row behind Austrian or Scotch pines, but this is not a good idea. Lombardy poplars grow fast and tall, but they're short-lived and very expensive to have removed after they die.
Any windbreak should be planted across prevailing winds, in our case north to south. Our prevailing winds in daytime are west to east, and at night as Earth cools, winds slide back toward the west, to the lower part of the Treasure Valley. We get occasional high winds from the south and the north at times, too.
Windbreaks can help preserve wildlife by providing cover from predators, nesting sites, food or just shelter from harsh weather. Planting native species such as Amelanchier (Serviceberry), or Mahonia (Oregon grape); crabapple or winterberry, for example, should work in a windbreak, causing few problems. Snowberry, buffaloberry, thimbleberry, bitter cherry, 4-wing Saltbrush, and other natives should tolerate natural precipitation after plants are established, and require little or no maintenance.
I wouldn't advise planting something unused to this altitude, such as chokecherry.
I did plant it once, after receiving a free shrub with a garden seed order. The chokecherry struggled to live, and was beset with tent caterpillars at one time; at another time it was defoliated by tomato hornworms.
The more rows of shrubs in the windbreak, or the denser the shrubs, the more solid the block of moving air. Shrubs such as Mahonia are very dense, so I wouldn't plant a thick row leaf-to-leaf of those if you want to filter the wind instead of stopping it.
If you have a driveway through the windbreak, you can angle the driveway without losing the protection of the windbreak.
SHOULD THOSE PINE NEEDLES STAY?
This time of year needles on pine trees turn yellow and drop. There'll be new growth in spring, new needles at the ends of twigs to replace those nearest the trunk that dropped off.
Some folks gather up those needles to use as mulch on other plants, but in view of roots' being less hardy than above-ground parts of shrubs and trees, the tree may need that mulch itself to ward off cold from its roots. If there's several years' accumulation of needles around the trunk, it should be safe to skim off some of them for use elsewhere.
I wouldn't leave the earth bare, though.
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