I have a thread going over on the Temperate forum but this is a general question that applies to anything:
If you have leaves showing discoloration/chlorosis/some other likely nutrient deficiency (as opposed to fungal/bacterial or other disease), would you not want to sample
these leaves -
as opposed to "healthy" leaves on the same tree(s) - in order to diagnose the issue?
I had a lab tell me specifically NOT to include the symptomatic leaves. I'm not sure if they were either misunderstanding my question or are just misinformed. Or perhaps it is I who am misinformed!
So, include the deficient leaves (only) or exclude them?