Plant invaders

ALAN Riach is correct in pointing out the benefits of non-native plants (Debate, 28 March). Let us not forget that what we call Ayrshire potatoes and Scotch tomatoes are in fact closely related to plants from South America. Further, let us bear in mind that the biggest single source of exotic, invasive plant species is the Scottish Government's own forestry policy.

Ron Greer, Blair Atholl