My neighbor has had a new cedar fence built and the contractor has sprayed the fence with an oil based stain.

Within 5 days the potatoes and tomatoes look very sick (yellow, leaves falling) despite having some covers put over them. One pumpkin plant is speckled and one has died.

Some plants do not appear to be affected, including some potatoes and tomatoes that were apparently covered with black plasic.

(a)How can I test the soil to see if there is a harmful residue
(b) What can I do to clean up the soil.

I am in North Dallas.

Thanks

Applying homemade compost is always the answer for healing potentially damaged or poisoned soil. Compost buffers soil pH, and it buffers many mild toxins via its aerobic microbes living in it.

Activated charcoal is also good for remediation of the soil.