In the marsh zone, the standing water
levels vary across the area and the sediment is not permanently covered by water. Water
levels rise and fall according to the amount of rainfall and run-off entering the wetland.
In many places there is no standing water, although the underlying sediment is
water-logged and anaerobic. In areas with standing water, the depth is rarely more than
10cm and usually as little as 1cm.
This area supports a much greater variety of plant
species (32) than the swamp area (17). However, there is a good
deal of overlap of species between the two areas. Species characteristic of this area
include Willow, Alder, Soft Rush, Yellow Iris, Branched Bur-reed, Greater Reedmace, Water
Mint and Wood Clubrush amongst many others. Isolated local mounds of trapped sediment
which raise the substrate above standing water levels are a feature of the area. These
allow a few plants belonging to species normally characteristic of much drier areas to
survive. (This includes species such as Bramble and Silver Birch.)
The invertebrate animals
inhabiting this area include a variety of spiders such as the Garden Spider (Araneus
diadematus), many different hoverflies, wasps and ichneumon flies. Dragonflies such
as Southern Hawkers (Aeschna cyanea) and the Golden-ringed Dragonfly (Cordulegaster
boltonii) patrol the area and damselflies and snails are common. In the spring, toads
and common frogs abound as they come to spawn in the open water and swamp areas of the
wetlands. Grass snakes can often be observed and roe deer come to lie up in the day time.