There are parts of the Amazon Rainforest in South America where you’ll find only one type of plant, and no other … and it’s all because of ants, in particular, lemon ants.

Lemon ants create these special forest areas — called devil’s gardens — by injecting a poison into the leaves of all the other kinds of plants. The poison, called formic acid, starts killing the plants within one day. Why? Because the trees the ants don’t kill have hollow stems that make perfect nests for their colonies.

The largest devil’s garden scientists have found so far has more than 300 trees in it and is around 800 years old.

(By the way, the ants that make those gardens are called lemon ants because that’s kind of what they taste like: lemons.)