Black Walnut Trees
Black walnut trees are sturdy hardwoods that thrive in our climate. They grow for a long time and provide lots of shade, and -- as the name implies -- produce an edible type of walnut. Apparently you can tap their bark in the spring and boil down their sap for syrup. When you cut them down you can use their corpses to make gun barrels and furniture.
In addition to shading out other plants, black walnut trees are infamous for secreting a toxin (called jugalone) that stifle the growth of plants near them. They grow at the expense of biodiversity around them.
Once a black walnut tree takes root in your yard you have a hard decision to make. If you keep the black walnut it will stifle the potential of your ecosystem. If you tear it out it will leave a void -- a toxic patch of earth that will take a lot of time and energy to remediate.
In my work, volunteering and personal relationships, I am a black walnut tree. Because I show up consistently people make the mistake of letting me get established. Then they have a difficult choice to make. Is it better to tear me out or do they let me continue poisoning their environment? Maybe it is better to prevent me from taking root in the first place.