NoOne N Particular wrote:
....

But back to the question, how hot is too hot?, etc. ...

Depends...

Ventilation, shade, humidity, work level, etc., etc., etc., ...

My general rule is 100F is hot, 105F is HOT, 110F+ is too hot for
anything except that which MUST be done (and a farmer's work is never
done, either)...

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