I am posting this message just in case you are suffering this weed on your
lawns.

We had at our house when we arrived an old Edwardian Tennis Lawn. This has
been used as a play area for many years but when the kids left home we decided
to work on it and turn it into a croquet lawn. But there were large areas of
field woodrush.

Experts who came in to help said there was nothing on the market that would
kill this weed.

But my old gardening books recommended nitro-chalk in order to create
conditions disliked by this plant. I duly applied it. There was no instant
effect, of course, but two or three years later I was suddenly aware that there
was no field woodrush anywhere to be seen and, as yet, it hasn't returned
although it is in other parts of the garden that I didn't treat.

Frankly I can't think what the purpose of the 'nitro' was other than to
encourage the grass to re-colonise the area. Its disadvantage was that the
only form in which I could buy this was pelleted, which meant that the
fertiliser tended to burn the grass for a while where it was concentrated. It
didn't show up, that much, of course, but in order to keep up with the
treatment (and not let the lawn return to its acid state again) I think I will
just add the chalk - assuming one can buy chalk in its powdered form.

Derek Carver
Oxshott, Surrey