VOLUNTEERS are continually being called upon to help in the preservation of rare plants.

What puzzles me is why these plants have become rare (Oxford Mail, August 1).

Since these wild plants have been growing here since, at least, the end of the ice age, what has changed to put their survival in doubt?

Agriculture has modified many fields to increase crop yield and, in the process, made certain areas uninhabitable for some of their former natives, but there must be uncultivated places where little has changed.

If left alone, surely, nature will guarantee rare plant survival without man’s intervention.

Derrick Holt

Fortnam Close, Headington Oxford