TREES OF CURTIS PARK: Inspect your trees for broken limbs or cracks

As winter storms roll in, the rain is a welcome respite from Sacramento’s hot dry summers. Wind usually accompanies major rainstorms and, depending on the severity, trees will shed large branches. In extreme cases, the entire tree may blow over.

During this storm season, remember to inspect your trees.

After every windstorm, I recommend inspecting trees for broken limbs or cracks at the branch unions. These problems should be addressed immediately by calling an ISA-certified arborist. This will limit damages to the tree and possibly to your property.

Cracks in large limbs or at the branch union require a tree support system. These are used to provide supplemental support for individual branches or entire trees by the use of cables, braces and guys. The goal is to provide support by limiting the movement of branches or the entire tree.

Large branches can pose a higher risk of failure due to weak unions or the length and weight of the limb. Branch unions that are narrow and look like a “V” are more prone to failure during windstorms than U-shaped ones.

Proper pruning can reduce the wind load of a tree. However, this may not be enough and that is when a support system should be used.

Cabling involves the attachment of stranded or braided wires between branches to restrict the distance that branches can move in relation to each other. Brace rods are used to reduce the risks of two or more significant limbs spreading further apart. They are also used to fasten together a branch union or branch that has split apart. Cobra, a support system introduced from Europe, incorporates the use of woven ropes that provide more flexibility than metal cables and requires no drilling into the tree.

The installation of support systems requires experience and skill, which is why many tree companies don’t offer this service. When done correctly, cabling and bracing can greatly extend a tree’s life and prevent removal. The placement of cables and rods is a controversial subject.

American National Standards Institute has developed guidelines for tree support systems. However, every tree will be different, and the arborist must understand the tree’s architecture.

The installation of a cablebrace system is no guarantee against failure because trees are subjected to environmental stresses beyond our control. Once installed, cable and Cobra systems require annual inspections.

Support systems are not just for trees that have breaks. They can also be used preventively to reduce the risk of branch failures. Proper care for older, mature trees may require a tree support system, which can be costly, but not when compared to the cost of tree removal.

The ubiquitous plane tree — commonly referred to as a sycamore — is one species that rarely needs a support system due to its branch structure. Conversely, the valley oak will greatly benefit from a support system. Curtis Park residents have been losing large valley oaks over the years due to catastrophic limb failures.

For questions or concerns about city trees, call the City Call Center at 311 or email 311@cityofsacramento. org. Urban Forestry will respond to any branches or trees that fall onto the street and sidewalk.

Written by Dan Pskowski and posted on Saturday, February 17th, 2018

Categorized: Trees, ViewpointTagged: