Can plants and trees really release deadly toxins?

Question

I just saw the movie "The Happening" and the point of the movie is that people are dying since plants and trees are releasing toxins into the atmosphere. Do you think this could be possible to happen??

Answer 1

that movie scared me LOL but i don't think that that could really happen.. i mean seriously think about it...... if they could wouldn't they have already

Answer 2

Yes, it is called allelopathy, and is frequently referenced with regard to walnut trees.  Many shade trees prevent other plants from growing beneath their leaves, but this is most often because other plants need more sunlight or because the spreading root system (of maple trees, for instance) steals all of the water.  Walnut trees actually secrete toxins that can kill horses and prevent other species from growing nearby.  Many websites are available to provide you with tolerant plant options. If you go to Johannsen's they can give you a handout listing tolerant species.