by Charlene Burgi
Winter is quickly approaching. Heavy rains and high winds—a dangerous combination—commonly accompany each other during Marin storms. Add a few improperly maintained evergreen trees and it won’t take long to find what makes this combination a recipe for disaster. Let’s look into the ingredients to see if this is a prizewinner or what can be done to correct the outcome.
Marin’s soil is typically clay-based. Clay soil holds onto moisture for long periods making drainage difficult, especially when storms dump multiple inches of rain in a short period of time. This creates the first ingredient: soil saturation.
Couple the soil characteristics of clay with the second ingredient: trees that are shallow-rooted such as pines, eucalyptus, redwoods, cypress and acacias, which are found covering our hilly terrain. These trees carry the third ingredient: maintaining a mass of leaves or needles during the winter that can form a wall or sail when the fourth ingredient of high winds is stirred into the mix.
This recipe often results in these beautiful giants falling down. There is one more ingredient that I omitted that can occur if the storm is coming in from a direction not commonly observed. Marin typically experiences westerly winds from off the ocean, and trees have built up their “strength” to buffer against such winds. But every once in a blue moon, a huge storm may come in from the northeast, and that, along with the above listed ingredients, can wreak havoc on those beautiful evergreens.
What can you do if you find these trees on your property? Enjoy the treasures that they bring but understand there is also a responsibility that comes with them.
Amend the soil when planting any of these trees.
- Refresh the mulch annually to keep the soil friable.
- Drain or grade the soil to draw surface water away from the root zone in winter by breaking down water dams.
- Hire a certified arborist who understands the need for thinning out the interior growth, so when the wind blows it will go through the trees and not meet a wall of limbs, needles or leaves!
- Do not top the trees as this only creates thicker growth and weak branch attachments that can cause broken limbs and create a different kind of hazard.
We never know what type of winter we face, but we can be prepared. Are you ready?