Science Questions

Can tress or plants feel?

Can tress or plants feel? What happens when you chop a branch off? Sylvia, Ipswich

We put this question to Dr Harriet McWatters:

Plants can detect it when you damage them in some way.  They are usually more sensitive to things like caterpillars eating them, which will happen in their natural life.  For example, an oak tree which is being attacked by caterpillars will respond by producing tannins in its leaves, which makes its leaves bitter.  What’s even more interesting is that trees adjacent to the one that’s being attacked can somehow detect some signal and will also start to produce tannins in their leaves, even before caterpillars have been eating.  So given that, I think they can almost certainly detect if a branch has been cut off.  The problem is that they don’t really have any response to that except to grow another branch.

July 2008