The clear waters of river Mimram on a sunny day, there are water plants in the river and there is vegetation on the banks. In the background is a meadow extending into the distance and a couple of trees against a blue sky.

The River Mimram at Archer's Green - one of just 240 chalk streams worldwide.

Birdseye view of Archer's Green nature reserve: the river Mimram can be seen horizontally bisecting the photo, in the bottom half is a green meadow, the top half is dry brown grass. The banks of the river are greenest and there are trees dotted along its length.

Birdseye view of Archer's Green and the River Mimram

The clear waters of the River Mimram, reflecting the dappled sunlight and revealing the pebble strewn river bed below the surface. Its banks are lush with green vegetation and to the right a tree hangs over the water.

River Mimram at Archers Green © Debbie Bigg

A wildflower meadow edged with trees extending into the distance.

Archers Green Nature Reserve © Debbie Bigg

Archer's Green

Floodplain grassland along the River Mimram chalk stream containing a mosaic of wet and dry grassland communities, marginal swamp, wet woodland, parkland trees, hedgerows, and diverse chalk stream habitat.

Location

Poplars Green (B1000)
Tewin

Hertford

Hertfordshire

SG14 2NQ

OS Map Reference

TL 27972 13392

Know before you go

Size

8 hectares

Entry fee

Free

Parking information

None

Access

Surfaced public footpath (TEWIN 022) and permissive grass footpath.

Dogs

Under effective control

When to visit

Opening times

Open at all times

Best time to visit

All year round

About the reserve

An idyllic section of the Mimram Valley containing a stretch of an internationally important chalk stream, flower-rich meadows and marginal wetland. Archers Green Nature Reserve consists primarily of lowland grassland home to rare Wildflowers and Butterflies adjacent to the River Mimram where you can find Water Voles, Brown Trout and Dragonflies.

Species

Habitat

Strategic importance

Archers Green sits in the Mimram Valley, a priority area for conservation action in Hertfordshire. The land is connected to other sites of importance for wildlife, adjacent to Panshanger Park and just one mile from the Trust’s Tewinbury Nature Reserve. These three sites are linked by the river Mimram.

Importance for wildlife

Covering 8 hectares, Archers Green includes priority habitats, identified in the Herts State of Nature Report. There are lowland meadows, wet woodland, marsh and chalk stream, supporting a wide range of rare plants and animals. This importance is recognised through its designation at a Local Wildlife Site. Chalk streams are internationally important habitats and this is one of the best stretches of the River Mimram.

Seasonal highlights

Spring - Meadow Saxifrage ; Grayling ; Marsh Marigold

Summer – Southern Marsh Orchid ; Dragonflies ; Water-Crowfoot ; Bats ; Yellowhammer

Autumn – Devil’s-bit Scabious ; Bats

Winter - Brown Trout