Information and Advisory Note Number 14                                                Back to menu

Waterside margins and their management

1. Introduction

1.1 This information and advice note aims to provide farmers with guidance on the creation and management of waterside margins beside flowing water and still waterbodies.

1.2 The margins of watercourses and ponds offer excellent opportunities for habitat creation and enhancement, as well as benefits for agricultural management. The value of a margin depends on its characteristics and the way it is managed. Basic characteristics include location (particularly relative to other habitats), dimensions, height above water level, and the existing variety of vegetation.

1.3 The benefits from waterside margins include:


2. Types of waterside margins


2.1 This information and advice considers three land use types and broad management regimes:

Landuse types:


Management types:


Usually the semi-natural habitat is managed for its wildlife value. Options for the management of margins on previously improved land are:


3. Benefits for agriculture and land management
 

3.1 Marginal vegetation can form an important buffer between a watercourse and agricultural activity on arable or grass fields (for example, fertiliser, muck and pesticide applications). The wider the strip and the more coarse the vegetation structure, the better will be the buffer effect.

3.2 Coarse vegetation can filter out silt carried by sheet run-off from farm land. The vegetation slows the flow of run-off, causing the sift and pollutants bound up with the silt to be deposited on the margin rather than in the water. Silt also holds considerable reserves of phosphate - an agricultural resource on the field but a pollutant in the watercourse. Soil erosion is an issue that should clearly be addressed at source by good land management.

3.3 Pollution by pesticides can be reduced in a number of ways:


3.4 Waterside margins reduce nitrate leaching by:

3.5 Reducing pollution from fertilisers and soil runoff can, in turn, slow the rate of silting and plant growth, avoiding the need for frequent dredging.

3.6 In arable situations, establishing a waterside margin along watercourses may have the following benefits:


3 7 Correctly managed, waterside margins beside arable fields can give added flexibility to access around the farm. Care must be taken to ensure that, wherever possible, the use of these areas for access does not cause too much disturbance to wildlife.

3.8 Management work which widens the waterside margin and provides improved grass or tree and shrub cover will generally enhance the landscape.


4. Benefits for habitat and species conservation.

4.1 Coarse vegetation at the waterside provides feeding, cover and breeding sites for


4.2 Fish benefit from bankside vegetation, which provides:


4.3 Vertical earthbanks provide nest sites for kingfishers and sand martins (particularly where a steep drop directly into water offers security from predators such as weasels). Solitary bees and wasps will also burrow into such banks for breeding sites.


5. Management of semi-natural waterside margins

5.1 Meandering watercourses create a variety of habitats which are lost with straightening or "canalization" of the watercourse. Management should aim to retain the meandering character and its associated habitats.

5.2 Watercourses often flow through semi-natural habitats such as unimproved grassland or wetland. The management of these features should aim to conserve and enhance the existing value of the site and should avoid overgrazing, undergrazing or inappropriate mowing regimes. Advice should be sought on their correct management.

5.3 Even where poor in plant species, wetlands can still be of high conservation value, particularly when subject to occasional flooding. Rough, rushy pastures provide an important habitat for invertebrates and are therefore feeding and breeding grounds for waders such as snipe, redshank, curlew and lapwing. Bam owls and other birds of prey hunt over rushy ground for voles.

5.4 In many situations waterside margins are uneven and rough, proving difficult to mow. For this reason controlled grazing by cattle is likely to be the preferred method of management. Ungrazed margins occur where stock are not available or where the ground is too wet or unsafe for stock.

5.5 If sites are left without grazing or mowing, scrub may develop naturally. While scrub is in itself a valuable habitat, the original semi-natural habitat is likely to be of more value. If archaeological features occur at the waterside, the development of scrub may result in damage by roots.


6, Developing waterside margins on improved-grass and arable sites

6.1 Reseeded and improved, grassland, arable land or set-aside can be left to revert or regenerate. Regeneration may come from the existing seed bank in the soil, seed from upstream sources delivered by the watercourse and other mechanisms of seed dispersal, such as animal and wind.

6.2 Regeneration will result initially in the development of rank vegetation with a poor range of species, and may include thistles and docks (plus some crop volunteers on previously arable land). While undesirable in the farming context this will have a value for overwintering invertebrates (many of which are beneficial for the natural control of crop pests), small mammals, seed and insect-eating birds and higher predators.

6.3 Where a weed problem does arise this can be controlled by spot-spraying weeds with those herbicides approved for use in or by watercourses and waterbodies.

6.4 The variety of plant species on regenerating or reverting sites will increase over time if given the right mowing and/or grazing management. In many arable areas farmers have rough toppers" for use on set-aside.

6.5 If preferred, regenerating/reverting sites could be left to progress to scrub cover. Unlike the development of scrub on semi-natural habitats, tree and shrub cover on improved ground is likely to a beneficial development for wildlife

6.6 An alternative to allowing regeneration or reversion of improved land Is to sow a wildflower mix. Again, management by grazing and/or mowing will be needed if a diverse, scrub-free wetland / grassland margin is intended.

6.7 On some waterside margins it may be desirable to plant native, marginal water plants which will diversify the habitat and give added cover. This is only advisable where the depth of the water will limit the spread of plants or where the owner is prepared to do any necessary management.

6.8 It is important to appreciate the effect that the use of arable land will have on the eligible area for Arable Area Payments. Set-aside and the Habitats Scheme make allowances for this. Similarly, putting grazing ground into an ungrazed use will affect forage hectarage. If in doubt consult a Scottish Office Agriculture, Environment and Fisheries Department (SOAEFD) officer.


7. Livestock access and the management of waterside margins

7.1 Sheep require little water, getting what they need from grazing. Cattle require access to water and can cause poaching and collapse of the margins. This could result in


7.2 Limited stock access to waterside margins can however produce benefits such as,


7.3 Limited, beneficial poaching is particularly productive for invertebrates, providing valuable feeding for,


8. Fencing waterside margins

8.1 Waterside margins require fencing where,


8.2 Where fencing is erected to exclude stock, it may be easier to provide alternative stock-watering facilities than to create breaks in the fence.

8.3 Include gates in all fencing (even if they are simple lift-gates). This allows for the introduction/removal of stock and the use of machinery as necessary.

8.4 in some instances temporary electric fencing may be all that is required to control periodic grazing.


9. Planting trees and shrubs on waterside margins

9 1 Trees and shrubs stabilise banks, limit erosion, provide shelter and wildlife habitat and are visually attractive.

9.2 Extensive dense woodland adjacent to watercourses and ponds is undesirable. Tree cover should be varied, comprising patches of overhanging trees and shrubs, dense scrub, scattered scrub, stands of tall trees with understorey and scattered tall trees.

9.3 Overhanging trees provide a source of insect food for fish plus leaf litter to feed aquatic invertebrates. They also provide fishing posts for kingfishers.

9.4 While some shade is beneficial to fish, dense shade may kill vegetation, reducing bank stability and causing an increase in undercutting and erosion. The effect is greatest on smaller watercourses. If shading is likely to cover much of the water,


9.5 The use of dense shade (from tree and shrub cover) is sometimes recommended as a means of controlling aquatic plants. This is appropriate as long as some areas of plant cover are retained elsewhere, to provide oxygenation, cover and feeding & breeding sites for aquatic life.

9.6 Retain large, old standing trees with good root-structure. This helps to stabilise banks and may provide a suitable location for an otter holt.

9.7 Planted species should be appropriate to the location, native and preferably of local provenance. Suitable species to consider are: willows, alder, rowan, ash and aspen


10. General management guidelines for waterside margins

10.1 For margins to be of greatest value to wildlife it is desirable to have a mix of habitats, incorporating tall and short grassland (some overhanging the water) and some tree and shrub cover.

10.2 When undertaking management work, such as dredging, ditch clearance and control of waterside plants, try to rotate the work, operating on different sections each year. Avoid management works such as these, as well as mowing/topping, when ground-nesting birds may be disturbed. Do not dump cuttings or material from clearance work on the bankside. Wherever possible dispose of this off-site.

10.3 There should be no direct application of pesticides, artificial fertiliser or organic fertiliser (farmyard manure or slurry) onto any waterside margin. The exception is the spot application of herbicides for the control of problem weeds or for weed control around planted trees and shrubs (see below).

10.4 If it is necessary to control waterside plants, use only those herbicides approved for use in or by water and ensure the removal of dead material from the site. Low intensity grazing or mechanical clearance is preferable to herbicide use. Herbicides usually offer only short-term control. Removal of certain species may lead to domination by other troublesome weeds.

10.5 Only a restricted range of herbicides has approval for use in/near water. The use of herbicides is strictly controlled and you should follow the recommendations of


10.6 When using herbicides:


10.7 Control problem weeds such as giant hogweed and Japanese & giant knotweed by spot-treatment only. Use only those herbicides approved for use in and by watercourses. Control giant hogweed by cutting all roots below ground level in May-June just before the seed-head is properly formed. Cutting at or above ground level allows abundant regrowth from the base and is seldom worthwhile. Alternatively consider treatment with glyphosate at "rosette" stage (March- late May). Follow up in succeeding seasons. Japanese and giant knotweed can be controlled by spot-spraying in July -August.

10.8 Before using herbicides for weed control consult with the appropriate River Purification Board / Environmental Protection Agency and Scottish Natural Heritage (on designated sites).


11. Sources of grant aid

11.1 The Environmentally Sensitive Area Scheme supports the conservation of waterside margins. The following ESAs will give annual (Tier 2) payments for the positive management and enhancement of water margins:


11.2 The Habitat Scheme operated by SOAEFD offers farmers within the watershed of the Don, Dee, Spey or Tweed payments for establishing margins of 6m - 20m width on improved grass or arable land. Stock are not permitted on the margin, which must be mown, with the cuttings disposed of responsibly and not fed to stock. Arable land entered into the Habitats Scheme on or after 1 July 1995 can count towards a farm's eligible Arable Area. Contact the local SOAEFD office for clarification.

11.3 Under the Arable Area Payments Scheme, guaranteed set-aside (or flexible set-aside, which is less valuable for wildlife) can be used to establish field .margins of 20m_ minimum width and at least 0.3 ha in area. This can be sited alongside watercourses and waterbodies and is subject to the management rules for guaranteed set-aside.

11.4 Grant may also be available from SOAEFD or SNH for management of waterside margins outside those catchments dealt with by the Habitat Scheme.

11.5 The Forestry Authority's Woodland Grant Scheme offers grants for establishing tree cover by planting or natural regeneration. This includes waterside locations.


12. Further Information

Further reading and references,

FWAG Scotland, Forth River Purification Board and Scottish Agricultural College (1995) "Buffer Strips"

Lewis, G and Williams, G (1994) "New Rivers and Wildlife Handbook9. RSPB/NRA.

Rebane, M and Andrews, J (1994) "Farming and Wildlife - practical management handbook'. RSPB

SNH (1996) "Freshwater Macrophyte Control" - Information and Advice Note 3.

SNH (1996) "Grazing Management -unimproved and herb-rich pasture" -Information and Advice Note 8.

SNH (1996) The Management of unimproved lowland grassland for nature conservation" -Information and Advice Note 11.

(Scottish Native Woodlands expect to produce advisory leaflets on re-establishing waterside tree-cover by spring 1996)


Authors:

Jeremy Roberts, Research and Advisory Officer - Agriculture and Land Management.

Vyv Wood-Gee
Countryside Management Consultant
Scabgill
Braehead
Lanark, ML11 8HA


Contacts for advice and information:

Jeremy Roberts, Agriculture and Woodland Environments Branch (AWEB)

Daniel Gotts, AWEB

David Howell, Aquatic Environments Branch

Research and Advisory Services Directorate
2 Anderson Place,
Edinburgh, EH6 SNP
Tel: 0131-447 4784
 

 

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