Overview

As traditional uses of heathlands and ‘Poors Allotments’ declined, scientific interest in the heathland, bogs, fens and wet woodland of Holt Lowes increased, and its value for wildlife was increasingly recognised. It was included on the very first list of 182 sites proposed as nature reserves in England in 1915. The Lowes also has a long association with Gresham’s School. It has been used for biology fieldwork, and staff and pupils from Gresham’s have also put much effort into conservation work on the Lowes. Holt Lowes is an SSSI (Site of Special Scientific Interest) and part of the Norfolk Valley Fens SAC (Special Area of Conservation). These paper designations help to protect the Lowes’ wildlife from some threats, but in common with most special places for wildlife the Lowes needs to be actively managed if it is to maintain the number and variety of plants, animals and other creatures that call it home. For over 25 years the Trustees of Holt Lowes have been working with the Norfolk Wildlife Trust to protect and manage the Lowes. As ‘managing agents’ the  Trust has taken the lead in active management, and have invested a great deal of money, time and effort into the Lowes –  recognition of just how special it is.

Understanding why Conservation is necessary

The reason for a lot of conservation activity is due to the process of Succession. If it wasn’t for our activities most of lowland Britain would be covered in broad leaved woodland. This is called the Climax Community. It is a result of the process of Natural Succession whereby pioneer plants colonise bare ground (e.g. after an Ice Age) Their presence modifies the environment so that other plants can then move in and continue the change. There can be several stages but the final, self-perpetuating community is the Climax Oak(usually) woodland.

 A successional sequence is primarily determined by the climate and the nature of the substrate (soil/geology). There are many types,

Bare soil → grassland → scrub → woodland

Bare sands and gravels → heathers and gorses (i.e. Heath) → Birch scrub → woodland

Open water e.g. a pond → submerged vegetation → reeds at margins → alder carr → woodland

There are many more examples, but in all cases each of the intermediate stages are a transient community. However succession can be stopped naturally for example by grazing. This will maintain a grassland and prevent scrub formation. Such communities are called Sub-Climaxes.

The activities of man , since neolithic times up to the present day, have created many such sub-climaxes, greatly increasing community diversity and with it biodiversity.

In our modern world many of these highly important sub-climaxes are no longer maintained by benign human activities that have gone on since neolithic times. Natural grasslands and heathlands are excellent examples. To make matters worse, airborne pollution in the form of nitrates originating from road traffic and agriculture, settle on the land and acts as a fertiliser, hastening the change from heathland to woodland. Although  predominantly rural, Norfolk is one of the worst areas in Britain for nitrate deposition, as the prevailing south-westerly winds carry pollution from across the entire width of England and Wales.

So to conserve the heath at Holt Lowes, we have to go back to why it has been maintained as such for centuries. Man has used the heath and prevented succession to scrub and the overgrowth of gorse. He has done this by

• Grazing his cattle, horses, sheep and pigs
• Cutting gorse and milling it to provide winter fodder for animals
• Cutting large gorse bushes to provide good starting fuel for bread ovens
• Cutting developing scrub and other trees for fuel in the home

We essentially use these methods in modern form to conserve the Heath. However it is an uphill struggle. When you look across the Lowes today you can see many trees. In 1960 you could see across the whole of the Lowes Heath. There were no trees to obscure the view!

Conservation on the Lowes Today

Volunteer work

Volunteer groups can have a significant impact in maintaining the habitats on the Lowes. This is especially true in areas not suitable for machinery, such as steep slopes or in the wet areas.

It is quiet amazing how much large gorse and birch can be cut and moved by a party of 10. The main valley mire has been our target this winter and the photographs show how successful it has been.

Also hand removal of threatening scrub etc is vital when we are protecting small and rare plants. Some of this sort of work may be carried out be NWT specialist work parties

The valley mire, looking north at the end of March 2023. All the cutting and gorse removal had been done by the volunteer as shown in the pictures. All the cut material was then removed by NWT workers andf milled to put on the waste vegetation piles. A completely clear valley mire ready for plant growth in spring and summer 2023.

Work done by Norfolk Wildlife Trust

Winter

Winter is the main time to carry out large amounts of work because organisms like birds, reptiles and mammals are not breeding and so won’t be disturbed.

Forage harvesting

This is used to cut areas of gorse and heather that have got too large. It is absolutely vital to biodiversity to have a range of different ages of heath. Different species specialise in different ages of gorse and heather. The aim is to have a random and natural looking arrangement!

Tractor removal tool for uprooting birch and gorse

Cutting and treating the stumps with round up does not necessarily kill an established plant so this technique of uprooting is more successful and reduces the amount of work that has to be done later on.

The cut material is milled and then the millings are put on mounds of such cuttings.  They gradually rot down and provide a warm hibernation spot for grass snakes as well as a place for their eggs to be incubated. These harmless snakes have increased enormously as a result.

Summer

After the breeding season in late summer weed wipes on a tractor are used to kill birch and other saplings growing up through the heather. Also bracken which is an problem in certain areas may be treated with a selective herbicide.

Grazing

Grazing by ponies and cattle is a significant part of the conservation effort managed by NWT. After all grazing was in the past a major reason why the heathland was kept open

A herd of Dartmoor ponies forms the major thrust of this effort. They graze the whole of the Lowes, which is why its perimeter is totally fenced. They are not fed (except perhaps in periods of prolonged snow), because they have evolved to be able to survive on the plants found in such an environment. Their activities help to keep the wet areas from successional growth of reeds etc and stopping the grass become too long and rank. The also browse on the gorse in the winter!

However certain of the wetland areas have electric fences around them to exclude the ponies when they might damage the rare plants that are flowering. Also these wet areas provide an easier food source for them so they would spend more time in them and cause too much poaching of the ground. Some poaching is good for seed dispersal but not when it turns into a quagmire!

It is vital that the public do not feed the ponies or indeed the cattle. These are wild animals  and we don’t want them to become used to being fed. If this happens they will:

• Not do their job of eating the Lowes vegetation!
• And more importantly expect food from all the Lowes users. They will approach all users and may frighten those adults and children who are not used to being confronted by a herd of ponies.

The cattle are very hardy English Park cattle. They are not always on the Lowes and are moved elsewhere when necessary. They feed on different things to the horses and will browse on woody vegetation. They also are large and as they walk about and feed they tend to open up the denser vegetation.