Small white dots on spinach leaves
I have seen the same problem reported but no answer was given due to the lack of picture. Spinach looks healthy but it has lots of white dots mostly on the undersides of the leaves. It is most numerous at the bottom of the plants. The white dots feel like salt-like grains when I brush them off with my fingertips. They easily wash off without leaving any discoloration or sign of disease behind. I checked pictures on the net and they do not look like downy or powdery mildew.
What is it and is it safe to eat those leaves that had these white stuff on them? It started showing up on my lettuces, which are in the same bed but not on the same kind of lettuce in a separate bed.
thanks for the help,