| A small but very unusual dome of peat
with associated mire vegetation.
This small area of wetland has developed where water, in the form of a spring, appears at the surface at the junction of two geological deposits; permeable sands and gravels overlying impermeable boulder clay. The permanently wet conditions created by the impeded drainage have allowed the development of peat, slowly growing over many years into a domed structure. This unusual habitat is technically called 'rheotrophic hangmire' and is only one of four in Hertfordshire and Middlesex. Ther top of the peat dome supports an unusual spring-line fen and mire vegetation with prominent tussock sedge and marsh marigold. The rank vegetation around the peat dome is dominated by hairy willowherb, meadowsweet and great horsetail. Rarer plants include marsh valerian, ragged robin and marsh thistle. Studies of the invertebrates have revealed several rare spiders and beetles. In addition to the small peat bog area, there are two other parts to the reserve. The southern-most section consists of rank marsh vegetation with scattered scrub, and this is separated from the peat area by a small, grazed meadow, and a belt of mature scrub. Ridlins Mire is leased by the Trust from Stevenage Borough Council. |
 The reserve is managed by being mown, although it is hopes that
a traditional grazing regime can soon be restored. |
| Visiting |
 From Stevenage take the A602 towards Hertford. After a series
of roundabouts the reserve can be reached via a gate off Gresley Way. |
 Bus stop on Broadwater Lane; trains to Stevenage. |
 Accessible at all times. |
 Spring/summer |
 Wellingtons required. The peat dome is very wet at all times.
It is advisable to keep to the edges. |