Answer: Assuming the wood isn't pressure treated, it should be fine. If it was pressured treated with CCA, I wouldn't recommend using it around vegetables. There's a growth inhibitor called juglone within the bark, roots, leaves, stems and fruits of all walnut trees. Some plants are more tolerant of this than others, and will grow near walnut trees. Other plants are extremely sensitive and will not grow. I couldn't find information on whether that property carried over to "dead wood" but you might want to use the walnut shavings on a path away from plants, for example. Otherwise, I think it's a great idea to use the shavings as mulch!
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