Question: which plant is harmful?

Isabel Webb answered on 20 Mar 2014:

There are several reasons plants might be harmful.

The most harmful are poisonous plants, like oleander. Many plants contain poisons, which make you ill, or even dead. The most poisonous UK plant is water dropwort, which has been known to kill people in the past if they eat the root (but you would have to go looking for it!)

Carnivorous plants are also dangerous, although not really to us. If you were a fly, you might be scared. Or a rat in the case of the giant pitcher plant, which can eat them. These plants attract bugs, trap them using something sticky and then release digestive juices that can break them down – imagine an inside out stomach. They then absorb the nutrients from the digested bug. These plants are pretty cool – we have some in the lab here.

Other plants might be harmful for reasons you might already have experienced – because they injure you. For example thorns on roses, or stinging nettles. In a forest you might trip on roots (if you’re clumsy like me..). It’s not that likely you’ll get seriously hurt, but it might make you a bit more careful next time.