Is it safe to build a raised bed garden out of 40-year-old treated wood?
For Veggies Absolutely NOT!

It is not safe to use for a vegetable garden. The problem is with the age. 40 years ago, wood was treated with poisonous chemicals. You don’t want that getting into your vegetables you will be eating. However, you can use it for a raised flower bed because you are not eating it. Modern pressure treated wood is safe to use in vegetable gardens.
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