Bringing Nature Home: How You Can Sustain Wildlife with Native Plants

by Douglas W. Tallamy

Dozens of common plants would make us quite sick if we were to eat them (Kingsbury 1964). Black cherry leaves, pokeweed leaves, and deadly nightshade all fall into the “poisonous” category for people. The tannins in oak leaves would bind up all of the protein we ingested, eventually starving us to death. Even many of the crops we do eat originally had toxic chemicals in their leaves before we removed them through plant-breeding programs that have been in progress for thousands of years. When we first domesticated lima beans, we discovered the hard way that if we don’t boil the beans, we risk a lethal dose of cyanide. The cucurbitacin triterpenes in cucumber leaves would kill us in short order if we could choke them down. And we all know the consequences of consuming nicotine from tobacco or opiates from poppies. In most cases, though, we have no trouble avoiding leaves containing such compounds because they taste so bad. Our lettuce has to be young and fresh or it gets too bitter for our fussy taste buds. We have all eaten cucurbitacins in minute quantities in the occasional bitter cucumber, but we don’t make that mistake twice in a row.