Summer in the Southwest

Moonsoon Tree Protection
The time period from June 15th through September 30th has been defined as "The Monsoon." A period of extreme heat is typically ongoing at its onset, which in the coming days or weeks is followed by an influx of moisture leading to daily rounds of thunderstorms. In addition, thunderstorms present an array of hazards which often strike suddenly and with violent force.

The term "monsoon" derives from the Arabic "mausim" meaning "season" or "wind shift."
It is, quite literally, a shift in wind direction that causes the meteorological event.
Depending on their size and duration, a downburst may be called a "macroburst" or a "microburst".

When preceded by heavy rain, a tree may be even more vulnerable to heavy winds, because in soil that is overly saturated, even a tree with healthy roots has a weaker hold. In this case, the bulk of the root system will become exposed if the tree falls over. Even one's best efforts cannot prepare a tree to withstand the fiercest of winds accompanying monsoon storms. However, there is a lot of preparation you can and should do to greatly diminish potential storm damage to your trees. Most importantly, do not ignore and neglect your trees. Look at them now and then!

Staking Trees

Staking provides a young tree with support it needs until the trunk is strong enough to hold it's canopy upright.

Most trees will not need to be staked longer than a year, but should be left for at least one growing season. As soon as the tree can stand on its own, remove the stakes.

Follow these guidelines for properly staking a tree:
  • Use 8 foot stakes or lodge poles (available at Moon Valley Nurseries). These stakes should be at least 6-8 feet tall and three inches in diameter.
  • Determine the direction of the prevailing wind and insert the stakes exactly opposite one another, about 2 feet from the stem, in line with the wind. For example: if the wind direction is westerly, then place the stakes North & South.
  • Drive the stakes vertically at least 2 feet into the ground. Try to bury the stakes so they are the same height above ground. When finished, stakes should stand upright at about 4 feet.
  • Cut 2 pieces of flexible wire, each measuring at least 5 feet long. Also, cut up an old garden hose into 2 eighteen-inch lengths. Then, slip the hose over the wire, and wrap the hose around the tree to protect the trunk from the wire. Pull equal lengths of the wire parallel to the ground and attach to the top of the stake. Twist the wires together on the outside of the stake to make the wire taut and nip off any excess.

"Three-fourths of the damage that trees incur during storms is predictable and preventable."

Care and Maintenance

Here are some defects to watch out for that make trees more vulnerable to wind and other severities of the weather:
  • Dead wood is unpredictable because it is brittle, and cannot give under pressure like living tree branches.
  • Cracks are clear indicators of potential branch failure, where there will be splitting sooner or later.
  • Decay, as evidenced by fungal growth or hollow cavities, is a sign of weakness.
  • Pests, such as the palo verde borer, can exacerbate a tree's health problems, but they typically target trees that are already sickly.
  • Can you see some sky through the tree? Keeping your trees thin is the single most important thing to do to "storm-proof" them. Quite simply put: the thicker a tree is, the more susceptible it is to damage in heavy winds. Even for a tree that is otherwise perfectly healthy, overly dense foliage poses a safety hazard during stormy weather. A dense canopy will not allow the wind to easily pass through, and the resistance to wind can cause branches to break or even bring the entire tree down. This especially applies to weight at the ends of branches, which is why stripping only the lower parts of the branches is not adequate (and leaves the tree with a funny lion-tailed look).

Here are a few more basic tips for avoiding storm damage:
  • Water, mulch, and fertilize the trees regularly and properly. Prevent the soil from becoming compacted.
  • Prune annually (or every two to three years, depending on the variety) even while the trees are still young. Having your trees trimmed by a professional who understands healthy tree structure is your best bet for avoiding problems.
  • Practice proactive tree care! Any money spent in preventive maintenance of your trees would most likely be dwarfed by the unexpected expense of a tree that falls down in your yard, even if it doesn't result in tree damage to buildings, cars, fences or other structures that would expensive to repair.

Weather statistics

Even though Desert Southwest rarely experiences a tornado, they do occur (an average of four every year). However, thunderstorm-generated winds can exceed 100 mph over a fairly large area, with the damage looking very much like tornado damage.

Damaging Wind Facts
  • 60-mph winds can lift the roof off a carport.
  • 70-mph winds can turn a mobile home on its side if the mobile home is not anchored to the ground.
  • 80-mph winds can lift the roof off a house.