Question: How can I tell the difference between wild perennial sunflowers and Jerusalem artichokes? If I eat the root of a perennial sunflower, will I get sick?
Answer: There are distinct but subtle physical differences between perennial sunflowers (Helianthus spp.) and the common Jerusalem artichoke (Helianthus tuberosus), which grows wild across the entire continental United States except for Nevada, Arizona, and New Mexico. The bright yellow flower heads of the Jerusalem artichoke are only about 2 inches in diameter and contain 8 to 20 outer yellow flowers (ray flowers) that enclose the dark yellowish-brown center. To be absolutely certain of what you’ve found, you’ll need to identify the other perennial sunflowers that grow near you and then compare them to what you believe is a Jerusalem artichoke.
Either way, perennial sunflowers are indeed edible. There’s a certain cultivar called ‘Prairie Gold’ that some people are now growing, especially those involved in permaculture or wildflower landscaping. Many people don’t find the thick rhizome of the perennial sunflower too enticing, especially because the plant is nowhere near as productive as the Jerusalem artichoke. That said, the plant is not toxic and can be used as food. The flowers make an interesting herbal tea, and the rhizomes can be used any way you might also prepare Jerusalem artichokes. -William Woys Weaver, seed and plant historian
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