In Norfolk, Hard Shield-fern, Polystichum aculeatum, grows on hedgebanks, on ditch banks (usually by hedges or in woodland) and on the woodland floor. Young plants are occasionally seen on walls, but there they rarely reach maturity. The plants are winter-green and as the surrounding vegetation dies back they become easier to spot.
Updated January 2019. Lime green circles and orange squares: 1987-1999 Green circles and dark red squares: 2000-2019
As can be seen from the distribution map, there are still two hectads where Hard Shield-fern hasn't been re-recorded since 2000 : TF90 and TG04