The California Sycamore, like the Valley Oak (largest oak in the world) sends a tap root down to the water table. It’s often as much as 100ft deep.
It’s how they take up water. Not from surface roots.
If the water table drops faster than they can sink the root, they die. And millions have during this drought. It’s a genuine tragedy.
Last summer I noticed all the dead trees around town. Trees that were on city properties. A lot of them were dieing from drought. Our local paper even did a story on how many trees around town had died/were dieing.