[GauntletWizard]

That's already happened - Rye is an example of Vavilovian mimicry[1][2], a crop that evolved to be hard for humans to distinguish from weeds. Thankfully, the selection pressure is also to be tasty and useful, as burning a field to prevent it's weeds from spreading remains a viable solution.

[1] https://www.indefenseofplants.com/blog/2016/2/2/the-accident... [2] https://en.m.wikipedia.org/wiki/Vavilovian_mimicry

[GauntletWizard]

Strike that, reverse it - A weed that evolved to be hard to distinguish from crops.