If unmanaged, dykes within grazing marshes may virtually disappear, being reduced to faint depressions. Work by Steve Harris at Gressingham, Norfolk, shows that the dyke network may be re-created with positive results. A 360° tracked excavator was used to dig out dykes along their previous positions, as shown by remnant hollows and old photographs. A diverse flora has regenerated, including marginal species such as Leser Spearwort, Ranunculus flammula, Ragged-robin, Lychnis flos-cuculi, Greater Bird's-foot-trefoil, Lotus pendunculatus, Water Mint, Mentha aquatica, Fen Bedstraw, Galium uliginosum, Fleabane, Pulicaria dysenterica, and Marsh Thistle, Cirsium palustre, and aquatic species including Water Plantain, Alisma plantago-aquatica, Water Starworts, Callitriche spp., Broad-leaved Pondweed, Potamogeton natans, and Stonewort, Chara sp.