What are the effects of eating diazinon-sprayed cherries before recommended 
minimum days-to-harvest are up?

Hello Ellie49

To quote the US Environmental Protection Agency, "diazinon residues in
food and drinking water resulting from agricultural uses do not pose
human dietary risks of concern".

It appears therefore that in "small" doses diazinon is not toxic to
humans.  Note - I use the term "small" here, by this I do not mean
that it is safe to drink or consume but if the fruit had been sprayed
and is now dry to the touch it is "safe".  These small doses are
generally termed residues or residual amounts.

Diazinon is an organophosphate that is harmful to the environment as
it accumulates in the food chain which could lead to levels that are
toxic to humans and other animals.  It is because of this that it is
unsafe to use in LARGE quantities and is restricted in use.

Diazinon can overstimulate the nervous system causing nausea,
dizziness and confusion.  At very high levels respiratory paralysis
and death can occur.

Dietary risks from exposure to diazinon residues in food and drinking
water do not exceed the Agency's level of concern.

A very readable document on Diazinon can be accessed at the EPA website here:
http://www.epa.gov/REDs/factsheets/diazinon_ired_fs.htm

I hope this answers your question.  If you have any further questions
on this subject please ask for clarification and I will do my best to
help you.

Thanks very much for the excellent answer and the link.  I very much
appreciate your time in answering this question.