There’s more to pruning than meets the eye, and timing is everything. A May 1, 2014 piece posted on the Michigan State University Extension website reveals an interesting detail about pruning (or not pruning) oak, in particular, during a specific period:

Pruning-Oak-Trees

“Oak wilt, caused by the fungus Ceratocystic fagacearum, is a lethal disease of oaks and has been detected in 44 Michigan counties. One way oak wilt spreads is through disease spores carried on the bodies of sap beetles as they feed from tree to tree. These sap beetles are attracted to fresh wounds. With warmer weather (albeit slow), oak buds are swelling, signaling the activity of the fungus causing oak wilt and the sap beetles that transmit this deadly disease. All that’s missing now is fresh wounds in oak trees.

Homeowners can reduce the risk of oak wilt infections by not pruning or otherwise injuring oaks after April 1. While high risk of infection decreases to low risk after mid-July, it’s prudent to simply avoid pruning oak trees from just prior to bud break to leaf drop. This means April to October.”

The article proves that pruning should be done with the proper know-how. It is best to leave the oak tree alone, for example, if there is no immediate need to prune it, to prevent oak wilt. If homeowners must prune their oak trees for safety or aesthetic reasons, they should get the expert advice of a reliable tree service in Palo Alto before starting the project.

It is helpful to note that California is home to different kinds of oak trees, from the California Black to the Coast Live. The fungus that affects sap beetles affects different oak trees, too, from the Swamp White to the Deer Oak. Each oak tree has its unique pruning and handling needs. Improper pruning and handling can endanger these trees.

In addition to oaks and deciduous trees, the Golden State has a rich array of riparian trees, redwoods and pines, which all require different times to prune. Residents can choose not to prune them, but this may put the trees and the structures surrounding them at risk.

Homeowners with various tree types in their property should engage the services of a reputable arborist in San Jose for tree maintenance. Not only do tree services like the Bay Area Tree Specialists know the proper time and technique to prune native California trees, but they can also expertly handle the tools used.

Pruning is a necessary task to ensure that trees are well-maintained and are in their finest form. Ill-timed pruning, however, can lead to a tree’s demise. Hiring tree experts is the best solution to ensure proper care of trees.

(Source: Avoid oak wilt by not pruning oak trees April-October, Michigan State University Extension, May 1, 2014)