Are there any wood shavings as mulch that are harmful to plants?

Question

I'm a woodworker and often use my wood shavings to mulch my veggie garden. My main concern is for the Coast Redwood shavings because of the Tannic acid. I also use alot of white cedar and the plants I'm mulching are strawberries, onions, lettuce and beets. I live on the west coast and the soil is acidic. Are there any types of woods that shouldn't be used in the garden?

Answer 1

I've recently discovered that oak leaves will kill grass, there is a component in the leaf matter that does this so that the oak seedlings will have a greater chance for survival. Oak wood is likely to have this same component.

Cedar is known to inhibit growth of microorganisms, it could poison the soil. It would be a good mulch if you don't want anything to grow underneath.

How are your plants doing with the amendments so far? Do you have a control area that is free of the shavings to compare?

Answer 2

besides the obvious of treated lumbers that you never want to use. wood is safe to use just be sure not to upset the balance of the soil. Each wood type has a specific charateristic. I use pine needes and pine bark to mulch around tomatoes and strawberries to increase the acid level of the soil. white cedar is more of a base and can be used around plants requiring less acid.