Oleander Leaf Scorch
Indentification: Leaves to begin turning yellow from the outside edges toward the middle (usually the tips). After pruning, new growth will occur, but the same outcome as above will occur.
Treatment(s): None. Plant removal because it is a bacterial infection.
More Resources and Support
https://www.gardeningknowhow.com/ornamental/shrubs/oleander/oleander-plant-diseases.htm
http://ipm.ucanr.edu/PMG/PESTNOTES/pn7480.html