PROLOGUE to the River Friend Series

An incomplete draft is Produced here for initial reference, but will also be available as a published printed book once the script and illustrations are done. A few illustrations of aquatic plants which will be in the completed printed book are shown below this text.

This is a Prologue to the River Friend series of books and is intended for reference only. Unlike the others, which concentrate on a particular river aspect, this book shows what some water plants look like, with common and scientific names, as well as a glossary of terms used throughout the whole series, and a list of publications for further reading.

A PROLOGUE TO THE SERIES: Plant identification and Glossary of Terms

1. How to Recognise Water Plants
2. Glossary of Riverine and Riparian terms used in the Series
3. Selective Bibliographical References and Further Reading

1. HOW TO RECOGNISE WATER PLANTS

Why do we use scientific names instead of common names?

Every recognized species on earth (at least in theory) is given a two-part scientific name. This system is called “binomial nomenclature”. These names are important because they allow people throughout the world to communicate unambiguously about animal and plant species.

Why do plants have scientific names?

Plants have Latin names due to the genus and species system of naming plants developed by famed Swedish botanist, Carolus Linnaeus (1707–1778).

How plants are named scientifically?

The binomial system of nomenclature is structured so that the scientific name of a plant consists of two names: (1) the genus or generic name, and (2) the specific epithet or species name. There are rules to follow when writing a scientific name. In handwritten scripts, the name is always underlined or italicized, or bold in print. To be really accurate a name or initials may follow the species name: but not in italics, viz. carrot, Daucus carota L. “L” goes back to Linnaeus, who named it. Complexities arise when taxonomists get to work and change things, e.g., Alder (English common name—easy!). Alnus glutinosa (L,) Gaertner—Alnus rotundifolia Stokes, originally named by Linnaeus. Forget about why this might be, and just copy it! (Use first name given, but check in the list below for the last one.)

Some common or ecologically useful watercourse species (listed alphabetically)

Latin Name Common Name(s)

Acorus calamus sweet flag
Agrostis stolonifera Fiorin, creeping bent
Alisma plantago-aquatica water-plantain
Alnus rotundifolia alder (Alnus glutinosa (L,) Gaertner)
Apium nodiflorum water celery, fools water-cress
Azolla filiculoides water fern

(Benthic algae) (green patches on bed)
Berula erecta water celery, lesser water-parsnip
(blanket weed) (long trailing green algae)
Butomus umbellatus flowering rush

Calamagrostis
Callitriche spp. (term includes: C. obtusangula, C. platycarpa, C. stagnalis water starwort)
C. hamulata intermediate water starwort
Caltha palustris kingcup, marsh marigold
Carex acuta tufted sedge
Carex acutiformis, C. riparia pond-sedge
Carex pendula pendulous sedge
Carex rostrata bottle sedge
Catabrosa aquatica whorl-grass
Ceratophyllum demersum rigid hornwort
Chara hispida
Chara spp.
Crassula helmsii

Drosera anglica great sundew
Drosera rotundifolia sundew

Eleocharis acicularis slender spikerush
Eleocharis palustris common spikerush
Eleogiton fluitans floating scirpus
Elodea canadensis Canadian pondweed
Elodea nuttallii
Enteromorpha freshwater and marine algae
Epilobium hirsutum great hairy willow-herb, codlins and cream
Equisetum palustre marsh horsetail
Eriophorum angustifolium common cottongrass
Filipendula ulmaria meadow-sweet

Glyceria declinata Sweet grass
Glyceria fluitans long-/short-leaved floating-grass
Glyceria maxima reedgrass, reed sweet grass
Glyceria pedicularis grass
Groenlandia densa opposite-leaved pondweed

Heraclium montegazzianum giant hogweed (POISONOUS)
Hippuris vulgaris mare’s-tail
Hottonia palustris water violet
Hydrilla verticillata hydrilla
Hydrocharis morsus-ranae frogbit
Hydrocotyle vulgaris marsh pennywort, common pennywort, water naval, money plant, lucky plant or copper coin

Impatiens glandulifera Himalayan balsam, policeman’s helmetImpatiens capensis
Iris pseudacorus yellow flag, yellow iris

Juncus articulatus jointed rush
Juncus bulbosus bulbous rush
Juncus effusus soft rush
Juncus inflexus hard rush
Juncus subnodulosus blunt-flowered rush

Lemna minor agg. (L. minor plus L. gibba) common duckweed
Lemna minuta least duckweed
Lemna polyrhiza greater duckweed
Lemna trisulca ivy-leaved duckweed
Littorella uniflora shoreweed

Mentha aquatica water mintMenyanthes trifoliata bog bean
Mimulus guttatus monkey-flower
(mosses) mosses
Myosotis scorpioides water forget-me-not
Myriophyllum alterniflorum alternate-leaved water milfoil
Myriophyllum spicatum spiked water milfoil

Najas flexilis slender naiad
N. marina holly-leaved naiad
Narthecium ossifragum bog asphodel
Nasturtium officinale agg. water cress (formerly Rorippa nasturtium-aquaticum)
Nuphar lutea yellow water-lily
Nymphaea alba white water-lily
Nymphoides peltata fringed water-lily

Oenanthe crocata hemlock water-dropwort (POISONOUS)Oenanthe fluviatilis river water-dropwort
Osmunda regalis royal fern

Parnassia palustris grass of Parnassus
Petasites hybridus butter bur
Phalaris arundinacea reed-grass, reed canary-grass
Phragmites australis reed, common reed
Pinguicula vulgaris butterwort
Polygonum amphibium amphibious bistort
Potamogeton alpinus red pondweed
Potamogeton coloratus fen pondweed
Potamogeton crispus curled pondweed
Potamogeton friesii flat-stalked pondweed
Potamogeton gramineus various-leaved pondweed
Potamogeton lucens shining pondweed
Potamogeton natans broad-leaved pondweed
Potamogeton nodosus loddon pondweed
Potamogeton pectinatus fennel pondweed
Potamogeton perfoliatus perfoliate pondweed
Potamogeton polygonifolius bog pondweed
Potamogeton sparganifolius ribbon-leaved pondweed

Ranunculus spp. water crowfoots, short-leaved, medium-leaved, and long-leaved
Ranunculus flammula lesser spearwort
Ranunculus hederaceus ivy-leaved crowfoot
Ranunculus omiophyllus round-leaved crowfoot
Ranunculus sceleratus celery-leaved crowfoot
Rorippa amphibia great yellow-cress
Rorippa austriaca
(Rorippa nasturtium-aquaticum) (see Nasturtium officinale above)
Rumex hydrolapathum great water dock

Sagittaria sagittifolia arrowhead
Salix alba white willow
(Schoenoplectus lacustris) (see Scirpus lacustris)
Scirpus fluitans floating clubrush
Scirpus lacustris common clubrush, greater rush, bulrush
Scirpus maritimus sea clubrush
Scirpus sylvaticus wood clubrush
Scrophularia nodosa figwort
Solanum dulcamara bittersweet, woody nightshade
Sparganium angustifolium floating bur-reed
Sparganium emersum strapweed, unbranched bur-reed
Sparganium erectum bur-reed
Sphagnum spp. bog moss
Stratiotes aloides water soldier
Symphytum officinale comfrey

Teucrium scordium water germander
Typha angustifolia lesser bulrush, lesser reedmace
Typha latifolia bulrush, greater reedmace, cat’s-tail

Urtica dioica stinging nettle
Utricularia vulgaris greater bladderwort

Valeriana officinalis valerian
Vallisneria spiralis
Veronica anagallis-aquatica agg. (V. anagallis aquatica plus V. catenata) water speedwell
Veronica beccabunga brooklime

Zannichellia palustris horned pondweed

Tall monocotyledons

Tall monocotyledons grow in shallow non-scouring habitats: they are emerged species (except for the submerged form of Scirpus lacustris) so need shallow water, and as large stiff plants they are susceptible to scouring flow and erosion. Conversely, being tall and dense-leaved, where they can grow, they can shade out all shorter species. Therefore, the characteristic habitat is fringing the banks of larger streams, and covering the bed of small ones with slow flow or negligible water (though not dry). When plentiful, they hinder flow, and so may be cut, dredged or sprayed. In watercourses they are usually restricted to water up to 1 m deep. Weed control to prevent them dominating deeper channels is unnecessary.

Tall monocotyldon distribution is thus controlled by a combination of:

1 Depth of water and availability of substrate suitable for anchorage and nutrition (reasonably soft but firm, and (except for Carex rostrata) not nutrient poor).

2 Water flow. Swift flow, whether continuous (e.g. highland or larger chalk streams) or intermittent (frequent storm flows) prohibits tall monocot clumps (in its path of full force).

3 Management practices. Rivers shoal, and shoal especially where abundant silt comes from the rock type (e.g. clay) or the land use (e.g. intensive farming). The shoaling occupies water space, so increases flood hazard. On shoals, fringing tall monocots can grow down into the water – if there are good substrate and (necessarily) lack of scour. This adds to the flood hazard.

4 Pollution. Pollution, of course, restricts or prevents development.

When water depth is reduced, by over-abstraction, land drainage or drought, water depth, and force of flow are reduced, and tall monocotyledons can spread. They can therefore be used to monitor water force.

The most important tall monocotyledons in British watercourses are:

Acorus calamus
Carex spp. (particularly C. acuta, C. acutiformis, C. pseudocyperus, C. riparia, C. rostrata (highland))
Glyceria maxima
Iris pseudacorus
Phalaris arundinacea
Phragmites australis
Scirpus lacustris
Sparganium erectum
Typha spp.

Although each species has, of course, its own habitat range, they can also be treated as a group.

Phalaris arundinacea occurs the furthest into the highlands, growing even on rocky shores and ‘islets’ in hill rivers. In lowland rivers it is usually further up the bank, sometimes not even reaching to the water. It can tolerate nutrient-poor conditions. It seldom dominates stream beds.

Sparganium erectum is the most frequent, and often comes in next downstream after Phalaris arundinacea in hill rivers. Unlike the latter it does not grow far up banks, and mostly grows around water level. It spreads very rapidly when conditions become favourable – it will spread across stream beds. Outside dykes and ditches, such spread is due to water shortage, since in ‘proper streams’, (those measuring 4m and above), water depth and force prevent this.

Glyceria maxima most often occurs with high silt (downstream reaches, silt wetlands, etc.), and in water regime lies in between Phalaris arundinacea and Sparganium erectum.

Scirpus (Schoenoplectus) lacustris grows in deeper water. It is not a typical or usual bank-edge species, and only doubtfully belongs on this list. Its rhizome can anchor in a flowing-water river bed. With greater flow and depth, and earlier in the summer, Scirpus lacustris bears a sward of submerged leaves. The emerged shoots develop more with less water and in late summer. Although mid-river clumps of this species do not necessarily indicate water shortage, obviously they are commoner with water shortage.

Phragmites communis is infrequent in rivers, occurring mostly in brackish-water reaches. In wetland dykes and drains, though, it is common, thriving under moderate interferences and dominating shallow channels if unchecked. Acorus calamus is introduced, and its distribution is restricted. Its habitat resembles that of Sparganium erectum. Carex spp. and Typha spp. occur rather similarly to but sparser than Sparganium erectum. Iris pseudacorus is both sparse (except in north west Scotland) and rarely occurs in quantity.

Protected Plants

Most of these are unlikely to be met by investigators, but some may be locally abundant, e.g. Luronium natans (floating water plantain). It is ironic that Hydrilla verticillata (water thyme) is an explosive pest species in the southern USA!

Watercourse (or watercourse bank) plants protected under British law are:

Alisma gramineum (Ribbon-leaved Water-plantain)Carex recta (Estuary sedge)
Chara canescens (Stonewort)
Damasonium alisma (also in Red Data Book)
Elatine hydropiper (Eight-stamened Waterwort)
Eleocharis austriaca
Equisetum ramosissimum
(Branched horsetail)
Eriocaulon aquaticum (Common pipewort)
Euphorbia hyberna (Irish Spurge)
Euphrasia rivularis
Galium debile (Slender Marsh-bedstraw)
Hydrilla verticillata (Water Thyme, Indian Star Vine)
Iris versicolor (Blue flag)
Leersia oryzoides (Rice cut-grass)
Luronium natans (Floating water-plantain)
Najas flexilis (Nodding waternymph)
Najas marina (Spiny waternymph, Spiny naiad, Holly-leaved naiad)
Potamogeton nodosus (Longleaf pondweed, Loddon pondweed)
Riccia bifurca
Rorippa austriaca (Austrian yellow-cress, Austrian fieldcress)
Sagina normaniana (Scottish pearlwort)
Sagittaria rigida (Sessilefruit arrowhead)
Scirpus triquetrus (Triangular club-rush)
Senecio congestus (swamp ragwort, northern swamp groundsel, marsh fleabane, marsh fleawort, clustered marsh ragwort, mastodon flower—presumed extinct in the UK)
Senecio paludosus
Teucrium scordium (Water germander)

Introduced Plants

Several species of watercourses and their banks are introduced (1 = Spreading, causing concern. 2 = Explosive growth in nineteenth century. 3 = Poisonous):

Acorus calamus (Sweet flag)
Azolla filiculoides (Water fern)
Calla palustris (Water arum)
Crassula helmsii1(Swamp stonecrop, New Zealand pigmyweed)
Egeria densa (Brazilian waterweed)
Elodea callitrichoides (Ernst waterweed)
Elodea canadensis2(Canadian pondweed)
Elodea nuttallii (common form)1 (Nuttall’s waterweed)
Fallopia japonica/Reynoutria japonica1(Japanese knotweed)
Heracleum montegazzianum3(Giant hogweed)
Hydrocotyle ranunculoides1 (Floating pennywort)
Impatiens capensis (Orange jewelweed)
Impatiens glandulifera1(Himalayan Balsam, Kiss-me-on-the-mountain, Policeman’s Helmet, Bobby Tops, Copper Tops, Gnome’s Hatstand
Iris versicolor (WBlue Flag
Lagarosiphon major (African elodea, Curly waterweed)
Lemna minuta1(Least duckweed)
Lysichoton americanus (Yellow skunk cabbage, Swamp lantern)
Myriophyllum heterophyllum (variable-leafe watermilfoil, parrotfeather)
Myriophyllum verrucosum (Red water-milfoil)
Sagittaria rigida (Sessilefruit arrowhead)
Vallisneria spiralis (Tapegrass)

2. GLOSSARY OF RIVERINE AND RIPARIAN TERMS USED IN THE SERIES

Abstraction drawing off water (e.g. from below the ground in soft limestone or sandstone, from a river, from a spring).
Acid poor in nutrients, of low pH (see dystrophic, oligotrophic).
Agg. (aggregate) used after a plant name to denote an aggregate of species which are difficult to identify separately.
Agrochemical chemical used in agriculture, e.g. fertiliser, herbicide, pesticide.
Agriculture cultivation (tillage) of the land.
Algae small green plants, not composed of stems, roots and leaves. Strictly, chlorophyll-containing thallophytes, which usually grow immersed in water (fresh or marine).
Alien belonging to somewhere else, to another country or continent. Believed on reasonable evidence to have been introduced.
Alkaline with relatively high amounts of bases, such as lime; with pH above 7.
Alluvial clays usually clay, silt or gravel which has been carried downstream by fast-flowing waters, then deposited where the flow slows enough to allow the floating sediment to settle.
Alluvial plain flat tract of country composed of alluvium
Alluvium deposits of silt (sand, etc.) left by water flowing over land which is not permanently submerged; especially those deposits left in river valleys and deltas.
Alpine in river types, used in a technical sense for the most steep hill landscapes, with falls from hill top to upper stream channel of 305 m and more (or rainfall very high), upper stream channels sloping steeper than 1:40, hill height usually over 610 m and great liability to spate.
Alternate arrangement of leaves, etc. placed singly at different heights on the axis or stem, not opposite or whorled.
Amenity pleasantness of feature, view, etc., pleasantness for human life.
Angular with corners, as of stems, leaf outlines, etc.
Anion electronegative substance such as nitrate, phosphate, sulphate and chloride (see cation).
Aquatic (1) living or growing in or near water. (2) A water plant or animal.
Aquifer rock which yields water.
Arable land fit for ploughing and tillage; not grassland, woodland or built-up land; bearing crops.
Archaeology scientific study of human antiquities.
Architecture structure; patterns and style built up; the art or science of building (including of vegetation, river banks, etc.).

Bank margin of a watercourse, in this scheme used for that part above normal water level, unless otherwise stated.
Basic rich in lime or similar alkaline mineral, and probably in other nutrients also.
Bed (of river) bottom or floor of watercourse.
Benthic of the bottom, the river bed.
Berm ledge, within or just above stream water-level.
Biocide killing life – herbicides, insecticides, pesticides, rodenticides, etc.
Biological of the structure and functioning of plants and animals.
Black Death a deadly bubonic plague, thought to be spread by rats, which ravaged communities across Europe, including Britain, from October 1347 to c. 1352 and was one of the worst human catastrophes in recorded history.
Blanket bog nearly flat tract of country composed of wet bog, wet acid peat.
Blanket weed filamentous algae (chiefly Cladophora) large enough to trail from the watercourse bed.
Bog wet spongy ground, consisting chiefly of decayed moss (especially Sphagnum) and other plants, nutrient-poor and acid.
Boulder clay clayey deposit of the Ice Age, affecting watercourses like clay.
Brook small stream.
Buffer able to neutralise extremes.
Buffer strip (zone) strip beside a watercourse, capable of cleaning (neutralising poisons in) water passing through to the stream.

Canal artificial watercourse uniting rivers, lakes or seas for the purpose of inland navigation (in various other countries, artificial channels used for irrigation or drainage).
Carbon essential element in organic compounds and hence life.
Carboniferous limestone is a collective term for limestones which occur widely throughout Great Britain and Ireland. They were formed between 363 and 325 million years ago.
Carnivore flesh (meat-) eating.
Carr wet or damp woodland, especially in East Anglia.
Catchment natural drainage area or basin, wherein rainfall is caught and channelled to a single exit point (= American watershed).
Cation electropositive substance, such as calcium, sodium, copper or manganese (see Anion).
Channel (1) bed and below-water sides of a watercourse (sometimes extended to include above-water banks). (2) Groove or furrow in leaf, etc.
Channelised watercourse deepened, straightened, made uniform.
Colour Band nutrient status band.
Community, plant the plants present in a site and their social ordering.
Conserve to keep entire, to manage in such a way as to keep entire, to preserve and care for.
Constructed wetland water purification works using an artificial marsh, usually of reed (Phragmites).
Control of flow restraint or regulation of flow, as a weir, dam, sluice, lock, etc.
Course channel for water and its direction.
Cover area occupied by, e.g. vegetation.
Covert shelter (covered-over part) for mammals and birds.
Cretaceous period 145.5 million years ago to 66 million years ago
Culture type of civilisation.
Culvert arched channel for carrying water beneath a road, railway, etc.

Dam structure to keep water back.
Debris dam small dam, often of tree trunk or branch, retaining debris.
Debris remains of plants, etc., broken down or destroyed.
Deflector groyne, a structure inserted to divert (or break-) water and drifting bed material.
Depauperate 1. of a flora, fauna, or ecosystem, lacking in numbers or variety of species. 2. of a plant or animal, imperfectly developed.
Detritus debris and other broken-down material (e.g. from river beds) usually broken down more than that referred to as debris (plant or animal).
Development working out, unfolding or new form of that which is already there. Used both for what is there in the river and for what is there in the mind of the developer.
Discharge total volume of water per unit time flowing through the channel.
Ditch a long narrow channel (hollow) dug to receive or conduct water, usually 0.5-2 m wide. In North America used synonymously with British dyke, drain, etc.
Diversity range of features or habitats, number of species present. Site diversity, number of species present in a given site area.
Drain drainage channel, the larger channels of the Fenland, etc., drainage system, usually 6–20 m wide.
Drainage drawing off water from the land.
Drainage Order stream order, analysis of the pattern of tributaries of a river.
Dyke an artificial watercourse for draining marshy land and moving surface water, usually 2–4 m wide. Derives from Anglo Saxon term meaning a large defensive ditch with hollow facing the enemy, bank facing the defenders.
Dystrophic of negligible nutrient content, acid and usually composed of or stained with, bog peat. For simplicity, used instead of dystraphent to describe species characteristic of such a habitat.

Ecology study of plants and animals in their habitats; mutual relations between plants and animals and their environment.
Ecosystem the land and water, the plants and animals in these and the functioning of all these together.
Ecotype a distinct form or race of a plant or animal species occupying a particular habitat.
Effluent outflow from sewage treatment works, factories, farms, etc.
Emerged (of plant parts) above water.
Emergent a plant mainly or entirely above water.
Enhance to rise in value, to add to.
Entire (leaf) without toothing or division, with even margin.
Ephemeral Plants with a swift life cycle, e.g., Blanket weed
Erosion scour, the removement of material from the channel of a stream.
Eutrophic of high nutrient status. For simplicity, used instead of eutraphent to describe species characteristic of such a habitat.
Eutrophication raising of nutrient status.
Evaluate to determine the value of.
Evapotranspiration the water lost to the air (in gas form) from the land or water plus that lost from the vegetation thereon.
Exotic introduced from a foreign country, alien.

Fen lowland, now or formerly covered with shallow water, or intermittently so covered. Peat is alkaline (contrast bog peat) because of the high base status of the water derived from the land around.
Fen peat peat developed in a fen.
Fertile nutrient-rich.
Fertiliser that which makes fertile, usually now meaning nutrients added as powders or sprays.
Flaccid limp, lax.
Flash flood storm flow in which water rises very rapidly, due to a combination of heavy rainfall and quick run-off in the catchment.
Flood (1) an overflowing of water over land. (2) A storm flow.
Flood gate contrivance for stopping or regulating the passage of water.
Flood hazard that which, by obstructing water movement, may or will cause flooding.
Flow water movement, quantity of water moving.
Flow type type or kind of flow, here negligible, slow, moderate, fast and rapid or white water.
Fosse Way was a Roman road in England linking Exeter (Isca Dumnoniorum) in South West England with Lincoln (Lindum Colonia) in Lincolnshire
Fragile watercourses watercourses whose habitat or ecology can be harmed or destroyed by a small change in land use or other aspect of human activity.
Fringing herbs group of semi-aquatic, rather bushy short emergents (dicotyledons), commonly fringing the edges of certain stream types, occurring more sparsely in a wider range of types.

Gauge, water gauge an apparatus to measure stream flow.
Geology geologic features (rock types, etc.) of a district, science relating to the history of the earth’s surface.
Geomorphology morphology of the earth’s surface.
Ground water level plane below which the rock or soil is saturated with water.
Groyne deflector, a structure inserted to divert (or break-) water and drifting bed material.

Habit characteristic mode of growth and appearance of a plant or animal.
Habitat kind of locality in which a plant or animal characteristically lives and grows.
Hardness ratio chemical parameter devised by Dr B. Seddon, calculated as the calcium-plus-magnesium content divided by the sodium-plus-potassium content (here, usually of silt-water).
Hatch flow-control with a half-gate that can be opened or shut.
Herb plant of which the aerial stem does not become woody or persistent.
Herbaceous plants not forming wood, but dying down every year.
Herbicide substance, usually synthetic, used to kill herbs, used for weed control.
Herbivore animal feeding on plants.
Heritage that transmitted from ancestors or past ages.
Highland high or elevated land. Used here in a general sense for hilly ground, and with the capital H, for the Scottish Highlands.
Hill natural elevation of the earth’s surface. Used here in a general sense.
Horseshoe wetland small pond or wetland dug in a buffer strip at the end of an under drain, so that the drain water is (partly) purified before entering the river.
Humus vegetable mould, brown or black substance resulting from the slow decomposition of organic matter.
Hydraulic pertaining to water as conveyed through channels.
Hydrology the study of water, water resources, in land areas.
Hydromorphology river basin management for water flow, energy etc. and surface feature processes and attributes of rivers, lakes, estuaries and coastal waters.

Impoundment (American) a pond caused by a dam across a stream, used for supply, water power, etc.
Improvement change for the better: ‘better’ being a value judgement. Hence improved drainage, more water removed from the land, improved farmland, greater crops, improved rivers, improved for conservation, drainage, navigation, fishing, etc., as relevant to context.
Infertile nutrient-poor.
Inorganic not formed from plant or animal parts (except when these have been completely broken down); mineral.
Invertebrate animals without backbone: insects, spiders, molluscs, worms, crustacea, etc.
Irrigation supplying land with water.
Jurassic Period 201.3 (+/- 0.2) million years ago – 145 million years ago
Land Drainage drawing off water from the land.
Leaflet a single division of a compound leaf.
Leat watercourse bringing water to a watermill wheel.
Legacy area part of river managed for plant and animal populations which can act as a source to colonise other areas.
Ley now describing temporary grassland.
Ligule thin projection from the leaf sheath, at the base of the leaf blade.
Lime-rich limestone forms predominantly on the sea floor where material rich in calcium carbonate (‘calcareous’ material) accumulates. This calcareous material may be organic, chemical or detrital in origin. Rivers flowing through limestones carry dissolved calcite in the water.
Loafing (birds) passing the time idly.
Lock (of canal, etc.) portion of the channel shut off above and below by gates and provided with sluices, etc. to let the water out and in; used to raise or lower boats from one level to another.
Low-nutrient lackingNutrients which are chemical elements critical to the development of plant and animal life. In healthy lakes and streams, nutrients are needed for the growth of algae that form the base of a complex food web supporting the entire aquatic ecosystem. The most common nutrients in lakes and streams are nitrogen and phosphorus.
Lowland low-lying land. In river types, used in a technical sense for land with not over 60 m fall from hilltop to stream channel in upper reaches, slopes of channels of upper streams flatter than 1:100, hills not over 245 m, with no (normal) liability to spate flows.
Lush luxuriant in unhealthy manner.

Macrophyte large plant, the higher plants (angiosperms), horsetails, water ferns, mosses, liverworts and the large algae (e.g. Chara, Enteromorpha).
Main River watercourses designated as such, in law, by the Environment Agency.
Marsh a tract of wet land, not bearing crops.
Meadow grassland mown (harvested) for hay (may be grazed at a different season of the year).
Meander bend in a winding course.
Median middle, of a line, etc.
Mesotrophic of moderate nutrient regime. For simplicity, used instead of mesotraphent to describe species characteristic of such a habitat.
Metabolism the process by which nutritive material is built up into living matter, or by which the complex substances of protoplasm are broken down to perform special functions.
Microhabitat subdivision of a habitat, in which one or more environmental influences differ somewhat to those of other parts of the same habitat, as stony and silty patches on a stream bed.
Micro-organism bacteria, viruses, smaller algae and fungi. Microbial to describe functions of these.
Migrant of birds, etc., one changing its abode from one country or region to another.
Mineral natural substance of neither animal nor vegetable origin.
Mobile able to move; of stream moving rapidly, not fixed.
Monocotyledon (Monocot) one of the two main groups of angiosperms (seed plants) having one seed leaf. Most often with narrow leaves and parallel veins. Tall monocot(yledon) term used to describe reeds, rushes and sedges.
Moorland uncultivated land with some (dry) acid peat or humus and much heather or similar vegetation.
Morphology study of form, of plants, animals, landscapes, etc., and the structures, etc. which influence that form.
Mountain large hill. In river types used in a specialised sense for land with the fall from hill top to the upper reaches of the stream channel of at least 185 m, the slopes of the channels of upper streams greater than 1:40, hill heights of at least 610 m, and rivers of much liability to spate.
Multi-stage channel watercourse which is on three or more levels in cross-section.

Navigable of a watercourse along which boats may pass.
Navigation (1) a navigable route. (2) A watercourse which (often in the eighteenth century) was developed for improved boat passage, on which tolls were paid, and whose rights could be bought and sold.
Neutral belonging to neither of two opposites, as acid and alkaline.
Niche ecological. Place or position suited to a particular plant species or community.
Nutrient serving as nourishment, normally used of inorganic substances necessary for plant growth, such as calcium, phosphate, etc.

Oligotrophic low in nutrients. For simplicity, used instead of oligotraphent to describe species characteristic of such habitat.
Omnivore animal feeding on animal and vegetable matter.
Oolite is a sedimentary rock made up of ooids (ooliths) made of calcium carbonate which are cemented together. Most oolites are limestones.
Opposite leaves. On both sides of the stem at the same level.
Organic of, or pertaining to, or composing plants or animals. Organic carbon the carbon in living or decomposing matter.
Ovalshaped like the longitudinal section of the bowl of a spoon.
Oxygenation supplying with oxygen.

Passage of birds passing through.
Pasture grazed grassland.
Peat plant material stored and partly decomposed under water. Found in fens (alkaline peat), bogs (acid peat), moors (acid peat).
Perennialflow of flow running throughout the year.
Pesticide chemical which kills pests. Usually used for synthetic chemicals killing small animals harmful for crop production or human health.
Physiography physical geography, description of nature.
Pinnate feather shaped, as with the leaflets of a compound leaf placed on either side of an axis.
Plain flat tract of country.
Pollard tree, usually willow (Salix spp) harvested regularly by cutting above the level at which livestock can graze.
Pollutant substance causing pollution.
Pollution the alteration of chemical status by human interference causing alteration to plant or animal communities.
Pond a small (usually) man-made waterbody or lake.
Ponding rising of water level because of obstruction.
Pool a small body of water, usually of natural origin, with slow or no water movement. As in pool and riffle sequence in streams. Also used for created deeper slower areas in streams.
Predator one that devours other animals.
Prey animals eaten by predators.
Productivity rate at which new organic matter is formed.
Propagule plant part used for propagation, such as fruit, seed, bulb, rhizome, winter bud, fragment.

Ramsar Convention is an international treaty for the conservation and sustainable use of wetlands, also known as the “Convention on Wetlands”. It is named after the city of Ramsar in Iran, where it was signed in 1971.
Rain shadowa region having little rainfall because it is sheltered from prevailing rain-bearing winds by a range of hills or mountains which block the passage of rain-producing weather systems and cast a “shadow” of dryness behind them.
Reach portion of watercourse which can be seen in one view, hence ‘lower reaches’ for the lower or downstream end of a river, and ‘upper reaches’ for the part near the source.
Reedswamp marsh dominated by reeds, sedges, rushes (tall monocots).
Regulation control and order imposed on the flow of a river.
Rehabilitation enhancement of the river towards its traditional habitat, flora and fauna.
Reservoir receptacle constructed, usually in a river course, to contain and store a large supply of water for ordinary uses.
Resident (bird), dwelling all year in the specified country or region, or, as summer resident, breeding there.
Restoration bringing back to a supposed former state. Returning to a close approximation of the traditional state that is persistent and self-sustaining. (To be used with care, River Restoration usually meaning enhancement.)
Rhizome perennial, horizontal root-like stem, usually underground but sometimes floating.
Rhyne, reen dyke and drain, South Wales, south west England.
Ribbed ofleaf, longitudinal veins prominent.
Riffle shallow section in a river where the water flows swiftly.
Rill small brook, rivulet.
Riparian of (or inhabiting) a river bank (ecology) relating to wetlands adjacent to rivers and streams.
River large stream of water flowing in a channel towards the sea, a lake or another stream.
Riverine 1. relating to, formed by, or resembling a river. 2. living or situated on the banks of a river.
Robust stream type not easily changed by minor interferences, strong.
Rock (1) material composing the hard surface of the earth, e.g. clay, limestone, Resistant rock, sandstone. (2) bedrock exposed in the channel or particles the size of boulders.
Run-off water flowing from, on and through land into watercourses, etc.

Salmonid fish of the family salmonidae, salmon, brown trout, sea trout, etc.
Secchi disc disk of specified type for measuring turbidity of water
Sediment particles which fall by gravity in water: mud, silt, sand, gravel, stones and boulders.
Seepage small water source oozing up through the ground.
Sewage human waste, detergents and other house chemicals, etc. More widely, and originally, all wastes carried by sewers, so including industrial effluent and urban run-off.
Sewage sludge solid wastes separated out in Sewage Treatment Works.
Sewage Treatment Works works constructed for the purification of sewage.
Sheath of leaf. Lower tubular part, usually enclosing stem.
Shingle coarse gravel, bed or bank of large stones.
Shoal submerged bank or bar.
Shrub a low woody plant, a bush.
Silting depositing silt.
Sinuous winding.
Skewed distorted, awry.
Sluice structure for ponding the water of a watercourse, provided with an adjustable gate or gates by which the volume of water is regulated or controlled.
Soil earth, substrate.
Solid rock all rock types except glacial drift and recent alluvial deposits. Solute a dissolved substance.
Spate large discharge or storm flow caused by heavy rains, etc., in hill streams where the water force is great.
Species group of plants or animals having certain common and permanent characteristics distinguishing it from other groups.
Spiling weave of willow (or other) branches used to protect watercourse banks (plug holes, plug erosion sites).
Spring flow of water rising or issuing naturally out of the ground.
Sterile barren, without life.
Stolon a creeping stem produced by a plant which has a central rosette or erect stem, when used without qualification, is above ground.
Storm flow the large water discharge that follows heavy rain.
Stream course of water flowing along a bed on the earth, forming a river or brook.
Stream Order drainage order, analysis of the pattern of tributaries of a river.
Stress pressure of some adverse force or influence.
Structure (1) constructions altering flow in streams, e.g. lock, weir, sluice. (2) Manners of organisation, arrangement of parts in and by rivers.
Submerged (of plant parts) within the water.
Submergent a plant within the water.
Subsoil stratum of soil lying immediately under the surface soil.
Substrate material near the surface of the bed of the watercourse, the rooting medium, the soil.
Summer-resident (bird). Dwelling and breeding in summer in a country or region.
Suspended solids particles diffused throughout the water.
Synergistic combined action greater than the sum of the component individual actions.

Tall monocotyledons group of tall emerged aquatics with long narrow leaves, potentially forming dense stands.
Topography morphological features of a region or locality.
Toxic poisonous, strictly a poison derived from a plant or animal.
Transfer water transfer. Movement of water, usually for domestic supply, from one river to another.
Translucent imperfectly transparent.
Trapezoid describing a channel with straight sloping banks and a flat bed, a quadrilateral with no sides parallel.
Tributary stream that runs into another.
Trophic of or pertaining to nutrition.
Turbid thick or opaque with suspended matter, cloudy, opaque.
Turions (in some aquatic plants) a wintering bud which becomes detached and remains dormant at the bottom of the water.
Two-stage channel watercourse which is on two levels in cross-section.

Under-drain small drain under field, to keep field soil dry for crops.
Unstable apt to change or alter.
Upland hilly country. In river types used in a specialised sense for land with falls from hill top to upper stream channels of 90-150 m, slope of channels of upper streams 1:40 to 1:80, hill heights of 245-365 m, and rivers with some liability to spate.

Vegetarian animal eating plants.
Vegetation plants in general, the plant life at a site.
Vein (leaf) strand of vascular tissue.

Watercourse stream of water, a river or brook; an artificial channel for the movement of water. The general term for water channels, including all other types defined here.
Water force integrated physical effect of water (on plants, beds and other objects) in aggregate.
Water-supported of plants supported by the water, floating and submerged species.
Water table plane below which the rock or soil is saturated with water.
Water transfer movement of water, usually for domestic supply, from one river to another.
Weir barrier and dam to restrain water.
Well spring, now usually a lined shaft sunk into the earth from which water is drawn.
Wetland low-lying flat land, damp or wet when without drainage.
Wetland dyke dyke in wetland, usually for drainage.
Wetland horseshoe small pond or wetland dug in a buffer strip at the end of an under drain, so that the drain water is (partly) purified before entering the river.
White water foaming water in rapids, etc.
Whorled (leaves) cyclic arrangement of leaves on a stem.
Winterbourne brook on soft limestone which has water flowing in a well-defined channel in winter, but dries in summer.
Wintering (bird) present in winter.

3. SELECTIVE BIBLIOGRAPHICAL REFERENCES AND FURTHER READING

A short history of Brewham URL: http://www.brewham.co.uk/ brewhams-history, September 2017. (Accessed 2 August 2019) . Brunning, R. (2006). Wet and Wonderful. Somerset Heritage Service, Taunton. Brunning, R. & Farr-Cox, F. (2005). The River Siger rediscovered. Archaeology in the Severn Estuary, 16, 7–15. Bunyan, J. (1694). The Pilgrim’s Progress. Defoe, D. (1724-26). A Tour Through the Whole Island of Great Britain (English Library, 1962).
Haslam, S.M. (1965). Ecological studies in the Breck Fens. I. Vegetation in relation to habitat. Journal of Ecology. 53, 599–619.
Haslam, S.M. (1965). The Breck Fens. Suffolk Naturalists Transactions. 13, 137–46.
Haslam, S.M. (1971). Physical factors and some river weeds. Proceedings of the European Weed Research Council 3rd International Symposium on Aquatic Weeds 1971, 29–38.
Haslam, S.M. (1973). The management of British wetlands. I. Economic and amenity use. Journal of Environmental Management. 1, 303–20.
Haslam, S.M. (1973). The management of British wetlands. II. Conservation. Journal of Environmental Management. 1, 345–61.
Haslam, S.M. (1975). River vegetation and pollution. In Science, Technology and Environmental Management. (Eds) R.D. Hey, T.D. Davis, pp. 137–44. Saxon House/Lexington. ISBN 0-347-01087-3.
Haslam, S.M. (1978). Keep those river weeds–they are useful. In Biological Surveillance of river water quality. (Eds) H.A. Hawkes, J.G. Hughes, pp. 30–54. From the proceedings of Section K, jointly with Section D, of the British Association for the Advancement of Science, Aston 1977. University of Aston, Birmingham.
Haslam, S.M. (1978). Macrophytes in relation to stream quality. In Elaboration of the scientific bases for monitoring the quality of surface water by hydrobiological indicators, pp. 109–14. Pollution Report 3, Department of the Environment and Central Unit on Environmental Pollution.
Haslam, S.M. (1978). River Plants. Cambridge University Press, 396 pp. ISBN 0-521-21493-9.
Haslam, S.M. (1981). (With P.A. Wolseley) River Vegetation: Its Identification, Assessment And Management. Cambridge University Press, 154 pp. ISBN 0–521-23186-8.
Haslam, S.M. (1981). (with R.F.A. Murfitt). Some unanswered questions relating to the mechanical control of weeds in water channels. Proceedings Aquatic Weeds and their Control, 87–94.
Haslam, S.M. (1981). Changing rivers and changing vegetation in the past half century. Proceedings Aquatic Weeds and their Control, 49–57.
Haslam, S.M. (1982). (With C.A. Sinker, P.A. Wolseley) British Water Plants. 1975. Field Studies Council. 108 pp. (Reprint With Corrections.) FSC Publication S10.
Haslam, S.M. (1982). A proposed method for monitoring river pollution using macrophytes. Environmental Technology Letters 3, 19–34.
Haslam, S.M. (1982). Indices for dyke vegetation. Nature in Cambridgeshire 25, 34–40.
Haslam, S.M. (1982). Major factors affecting the distribution of macrophytic vegetation in the watercourses of the European Economic Community. Proceedings EWRS 6th Symposium on Aquatic Weeds 1982, 105–112.
Haslam, S.M. (1982). Vegetation In British Rivers. Nature Conservancy Council. 2 Vols., 125 pp and 320 pp. ISBN 0-86139-203-5.
Haslam, S.M. (1983). (with F.H. Dawson). The management of river vegetation with particular reference to shading effects of marginal vegetation. Landscape Planning, 10, 147–69.
Haslam, S.M. (1984). Stream vegetation and pollution in Italy and Mediterranean France. Second International Symposium on Environmental Pollution and its Impact on Life in the Mediterranean Region. Second International Symposium of the Mediterranean Scientific Association of Environmental Protection (MESAEP), pp. 19–91. Munich.
Haslam, S.M. (1985; 1987). (with J.P.C. Harding, D.H.N. Spence. Authors not listed on title page). Methods for the use of Aquatic Macrophytes for assessing water quality. Methods for the examination of waters and associated materials. Her Majesty’s Stationery Office, London, 176 pp. ISBN 0-11-752000-4.
Haslam, S.M. (1986). Causes of changes in river vegetation giving rise to complaints. Proceedings EWRS/AAB 7th Symposium on Aquatic Weeds 1986, 151–6.
Haslam, S.M. (1987). River Plants of Western Europe. Cambridge University Press. 512 pp. ISBN 0-521-26427-8.
Haslam, S.M. (1987). Sources of watercourse pollution in Italy and Mediterranean France. Chemosphere, 16, 331–337.
Haslam, S.M. (1990). Phragmites culm strength and thatch breakdown: Some difficulties. Landschaftsentwicklung und Umweltforschung. Technische Universität.
Haslam, S.M. (1990). River Pollution: An Ecological Perspective. Belhaven Press, London, 253 pp. ISBN 1-85293-073-X.
Haslam, S.M. (1991). River pollution in some Mediterranean Islands. Toxicological and Environmental Chemistry, 31–32, 255–63.
Haslam, S.M. (1991). The Historic River. Cobden of Cambridge Press, Cambridge, 332 pp. ISBN 0-9517963-0-5.
Haslam, S.M. (1992). Pollution and the Public. Fresenius Environmental Bulletin, 1, 113–6.
Haslam, S.M. (1992). Rivers and river vegetation in North-Central Florida. 73 pp.
Haslam, S.M. (1994). Wetland Habitat Differentiation And Sensitivity To Chemical Pollutants (Non Open Water Wetlands). Her Majesty’s Inspectorate of Pollution, London. 145 + 110 pp.
Haslam, S.M. (1995). A discussion of the strength (durability) of thatching reed (Phragmites australis) in relation to habitat. Reed research report, Department of Plant Sciences, Cambridge. 56 pp. (Annual updates follow.)
Haslam, S.M. (1995). Cultural variation in river quality and macrophyte response. Acta Botanica Gallica, 142, 345–8.
Haslam, S.M. (1996). Enhancing river vegetation: conservation, development and restoration. Hydrobiologia, 340, 345–8.
Haslam, S.M. (1997). The River Scene: Ecology And Cultural Heritage. Cambridge University Press. 344 pp. ISBN 0-521-57410-2.
Haslam, S.M. (1998). (with F. Klötzli, H. Sukopp and A. Szczepanski). The management of wetlands. In The production ecology of wetlands. (Eds) Westlake, D.F., Kvet, J. and Szczepanski, A., pp. 405–64. Cambridge University Press. ISBN 0-521-22822-0.
Haslam, S.M. (1999). River patterns in landscapes. In Maudsly, M. & Marshall, J. (Eds) Heterogeneity in Landscape Ecology Pattern and Scale, pp. 169–75. International Association for Landscape Ecology (UK Region).
Haslam, S.M. (2001). Impact of land use changes on rivers. Aspects of Applied Biology, 58, 197–204.
Haslam, S.M. (2001). Retaining the cultural heritage of rivers? In: Mander, Ü, Haslam, S.M. (2010). Rintsmann, A. & Palang, H. (Eds). Development of European Landscapes, Vol. 1, 206–9, Tartu.
Haslam, S.M. (2002). Stream community lists as bioindicators. Proceedings of the 11th EWRS (European Weed Research Society) International Symposium on Aquatic Weeds, September 2–6, 2002, 243–6, Moliets et Maâ, France.
Haslam, S.M. (2003). Understanding Wetlands: Fen, Bog And Marsh. Taylor & Francis, London, 296 pp. ISBN 0-415-25704-8.
Haslam, S.M. (2006). River Plants of Western Europe. 2nd Edition. Forrest Text, Cardigan. 438 pp. ISBN 09550740 4 5.
Haslam, S.M. (2006). Whither river landscape ecology? In Davies, B.R. & Thompson, S. Water and the landscape, IALE (UK). International Association for Landscape Ecology (UK Chapter) pp. 3–7.
Haslam, S.M. (2008). The Riverscape and the River. Cambridge University Press, New York, 404 pp. ISBN 978-0-521-83978-5.
Haslam, S.M. (2009). The Reed. Rewrite. Available to download free from the British Reed Growers Association website in pdf format. A completely updated version of the original.
Haslam, S.M. (2010). A BOOK OF REED. (Phragmites australis (Cav.) Trin. ex Steudel, Phragmites communis Trin.). Forrest Text, Cardigan.
Haslam, S.M. (2011). Water: the greatest ecosystem service. In Landscape Ecology and Ecosystem Services. C. Young, L. Bosongel, I. Hooper & K. Moreton-Jones (Eds.) pp. 129–137.
Haslam, S.M. The Waving Plants of the River. (2013). Forrest Text, Cardigan. 278 pp. ISBN 978-0-9564692-4-3.
Hill-Cottingham, P.; Briggs, D.; Brunning, R.; King, A.; & Rix, G. (eds). (2006). Somerset Books, Wellington.
Matthews, G.E. (1929). “The drainage of the fens and marshlands of the Wash”, Journal Institution Municipal and County Engineers. p. 443.
Natural Environment Research Council (NERC). (2019) [Accessed 2 August 2019]: https://nerc.ukri.org/research/funded/programmes/droughts/.
Parker, R. (1975). The Common Stream. William Collins Sons & Co. Ltd. Glasgow. 283 pp. ISBN 0 00 216113 3.
Pevsner, N. (1958, 2003) (ed.). Buildings of England. South and West Somerset. Penguin. Yale University Press, New Haven.
Rippon, S. (1997). The Severn Estuary. Landscape evolution and wetland reclamation. Leicester University Press.
Rippon, S. (1997). The Severn Estuary. Landscape evolution and wetland reclamation. Leicester University Press.
Thacker, F. (1914). Thames Highway, Volume I, from “Where Thames Smooth Waters Glide”.
Tropical Agriculture Association. (June 2001). Bone, T. “Fresh water and crops in Malta”. In, TAA UK, Newsletter (now Agriculture for Development), pp. 25–29, 40pp., ISSN 1759-0604 (Print), ISSN 1759-0612 (Online URL: https://taa.org.uk/wp-content/uploads/2018/10/JuneNewsletter2001.pdf.
Victoria County History, Vols. 8, 9. (Founded 1899) .
Williams, M. (1970). The draining of the Somerset Levels. University Press, Cambridge.
Wolseley, P.A., Palmer, M.A., & Williams, R. (1984). The aquatic flora of the Somerset Levels and Moors. Nature Conservancy Council, England.

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