Phisherman expounded:

The treated ones will last a lot longer. The untreated will last 2,
maybe three years. I think someone who grows 100 plants or so will
buy te treated ones to save for furture years. They won't have any
effect on the tomatoes.

No, but they might have an effect on the people who eat the tomatoes.
Why take the chance? The money you save won't do you any good if
you're sick from the pressure treated wood. Buy the untreated and
replace them when needed or buy the coated steel ones for good.

--
Ann, Gardening in zone 6a
Just south of Boston, MA
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