Q.mulberry dropping leaves with brown spots
The yard is covered with brown-spotted yellow leaves from our three mulberry trees. Are the trees diseased?

This is a Leaf Spot fungus. It generally will not harm a tree but you should try to control it with
a fungicide treatment.
Clean up any dropped leaves on the ground around the tree and dispose of.
Here is a link with more information.
https://www.gardeningknowhow.com/ornamental/trees/fruitless-mulberry/possible-causes-of-a-fruitless-mulberry-with-yellow-leaves.htm