Answer: Hardenbergia violacea, or Happy Wanderer Lilac Vine, is native to Australia and sources there indicate the seeds may be poisonous to livestock. Before planting, I'd check with a local Vet or the ASPCA to see what test results might be here in the U.S. Since there is a possibility of toxicity, perhaps you and your neighbor can find another plant to grow along the fence line. Again, your Vet is your best source of information.
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