Diagnosing Sudden Leaf Browning on Newly Planted Live Oak

Likely Cause

If nearby trees (Chinese pistache) are unaffected, herbicide drift is unlikely. The most probable cause is planting too deep or a loose root ball from poor staking, leading to root desiccation and failure to establish.

Action Plan

1. Request replacement from the nursery.
2. Replant correctly: hole twice the root ball width, same depth. Do not plant deeper than the root flare.
3. Mulch 3 inches (keep off trunk).
4. Water 1 inch every 3 days for 2 months, then weekly.
5. Stake for one year only; remove stakes thereafter.
6. Do not fertilize the first year.