Hi, I have some questions regarding my oak trees. We basically just moved into our home and we have a ton of oak trees. I don't know much about oak trees and to me they look a little sad. Not a lot of leaves. I have had a few so called experts out and they all give me different answers so I thought you might be able to help me. 1. San Diego has been in a drought for a long time now. Should I be watering them? It's Sept now or should I wait for some hopefully rain....How much water and where do you water them (at the base or out more)? 2. Should I be trimming them? If they have small dead braches or branches with dead leaves? 3. How do you know if they are dying? I have some that have a lot of leaves that are green and brown or some that don't have a lot of leaves, either color.... 4. Should I put down mulch around the base? Should I also be spraying them for insects? 5. Should they ever have a line of sap on the trunk? Thank you for answering my questions. Like I mentioned above I have talked to other and everyone of them has given me a different answer. UG
California Oak Tree
Certified GKH Gardening Expert
These trees sound like they have some age to them. I do think that if you want them to grow to their best, then you will want to water them. The larger roots, at this point, are dedicated to keeping the tree up. Support. Now, the roots further out are responsible for collecting nutrients, and water. It is quite possible that they have a pH issue in the soil. This can be corrected with a simple broadcast of dolomitic lime.
Now, as for pruning. Yes... I would, most definitely prune out any old and/or dying growth. Not only is it unsightly, but it can cause a bad fungal issue. They will, naturally, grow how they are intended to by nature, but it doesn't hurt to help it along, now does it?
I am including a link to a few articles on care of the tree: https://www.gardeningknowhow.com/ornamental/trees/oak/