Why do many contemporary gardeners skip recommending Pennyroyal for fly control?

Answer

It contains pulegone, a potent compound generally considered toxic if ingested in large quantities

Although Pennyroyal contains the potent compound pulegone and acts as a repellent, it is often avoided in modern recommendations due to toxicity concerns if ingested by humans or pets.

Why do many contemporary gardeners skip recommending Pennyroyal for fly control?
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