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A plant one biologist said should be impossible 🧵 doi.org/10.1002/ajb2... Fed up of adverts for scams to earn a passive income? You’re going to hate this plant.

Corallorhiza striata, striped coralroot, is an orchid found in North America, and it hates paying for anything. A paper by Freudenstein and Barrett examines how it steals food from fungi and pollination from wasps. All orchids need a little help from fungi to begin with.

Orchid seeds are tiny, with no stored energy so they connect to the fungal network to start them off, until they photosynthesise their own food. Usually. Striped Coralroot never stops taking, even as an adult. It taps into Tomentella fungi. These fungi swap nutrients for sugars with trees.

This orchid gets into the network and takes without giving anything back. It also needs pollinators. Male *Pimpla pedalis* wasps are looking for a female, or rather smelling for one. Striped Coralroot pumps out its own scent to get attention,

and deposit the pollen on another flower. Both these approaches rely on the partner not being able to resist the orchid. If they could, they would. That makes any exploitative strategy a bit of a risk. Also a biologist, Bidartondo writing back in 2005 said you shouldn’t expect a plant to be

cheating two partners at the same time, because it means relying on getting things right for two very different partners at the same time, else you fail. What Freudenstein and Barrett have is evidence this kind of freeloading isn’t impossible.

The two approaches are both rare, but combine them and the maths says it should be possible, but very improbable around 2000 to 1. And when you look at observations it seems to be in the same ball park, around 4000 to 1. They only know of four other species of plant that are fully parasitic for food