Q.Sago Palm
My sago palm seemed very green and healthy just a few days ago, but I noticed today that the inner leaves are turning yellow. Can you tell me what is causing that?

Certified GKH Gardening Expert
There are several things that could be causing this. Because it was rather sudden on an established plant, the most likely cause would be a fungus. Try treating the plant with a fungicide. This article may give you some other ideas as to what is causing it:
https://www.gardeningknowhow.com/plant-problems/environmental/plant-leaves-turn-yellow.htm