Twig growth for the season should be from 3 to 24 or more inches in length. Bark growth cracks usually indicate that the tree is healthy. Tissue in the cracks should be bright green or pink when scratched. However, loose and discolored bark or unusually flattened areas on the trunk is indicative of a diseased condition. Minimize grading, digging, trenching, covering the ground with asphalt or concrete or landscape plants, excessive foot traffic, or vehicle parking.
Proper management maintains free passage of water and air within the root zone.
The area extending 6 feet from the trunk is the most vulnerable and should always be left undisturbed and uncovered. If pruning is necessary, trees should be pruned in the dry season. June and July is best. Native California oaks have evolved in a Mediterranean-type climate where there is little rainfall between late spring and early autumn. As such, they generally do not require irrigation during this dry period and, in fact, trees may be adversely affected by supplemental watering during this period since warm-moist conditions can favor harmful diseases.