Marginals

 

     The emerged plants are rooted in the soil of wetlands, the pond edge, or in the pond bottom in areas of shallow water, and have aerial foliage. This allows them to transpire like land plants; a solution of water and dissolved minerals is wicked upward to replace the moisture lost by evaporation. In other respects, these plants have a variety of special adaptations which allow them to survive with their roots submersed, clinging to unstable soils. This results in a symbiotic relationship benefiting the structure of the pond, and therefore other aquatic life forms. Roots spread near the soil surface at the water's edge and create a netlike barrier which resists erosion. This is an important function in a sensitive area where wave action and water flow might undercut banks and sediment the pond. These plants create habitat and food supply for many species of insect, bird, and mammal. Catail is an example of the type.

Arrowhead is an interesting plant as it
produces two kinds of leaves, the surface leaf that is shown in the picture and a subsurface strap-like leaf. There are a few different varieties within this group, but they all prefer shallow, sheltered waters. They die back in the autumn and are able to reproduce either vegetatively or by the production of seed, exposed mud being the best condition for seed germination. The seed is able to float and has a waxy coat for protection.

 

Typha angustifolia, known as the Cattail in
America, and the Lesser Bulrush in the UK, is a
very versatile plant preferring waters at least 0.5m (18 inches) deep. It is easily able to colonize open water where it can even extend over the water by creating a floating mat. Colonies spread either from rhizomes or by seed production. The rhizome can quite easily break loose and float across large expanses of water to colonize another area. It does not like extensive wave action as this may break up the rhizome system, but in doing this it is able to spread to what possibly may a more suitable location for growth.

 

Water Mint is quite a pleasant plant having a very strong aroma of mint as its name suggests. An early growing plant which seems to do well even when in competition with larger species. Leaves can be seen subsurface and it will produce lilac flowers. It is also said that mosquito's have a disliking for the scent from these plants

 

 

Mare's - tail can be found as a aquatic with submerged or emergent shoot or as a completely terrestrial plant. It tends to prefer growing at the side of ponds but as an aquatic is found in clear base-rich waters. It tends to prefer eutrophic soft substrata, and once present can become a very persistent species. The submerged shoots tend to be very different from those of the aerial form, and the switch only takes place under conditions of high light intensity and temperatures above 10ºC. In saying that aerial shoots can be found below water in very clear water there is no intermediate stage in the shoot production.

 

Water Horsetail (Equisetum fluviatile) is a versitile plant being found in a wide range of water conditions, it prefers shallow waters but has been recorded in exposed waters to 1.5 meters ( 5 feet). It also also able to grow on both aerobic and anaerobic substrates. The joined stems are the main structure and have whorls of branches at the nodes, leaves are reduced. Spreads by rhizome and vegative means.

 

 

 

    A relatively short emergent plant, Branched Bur-reed is normally found in narrow bands at the permanent waters edge. It is unusual to find it growing in large concentrations apart from swamps or badly silted waters were it will grow on liquid mud. They are a useful plant as they help to stabilize banksides and offer cover for many edge species, this added to them confining themselves to shallow water makes them a desirable marginal plant.

 

 

 

    Water Plantain is a species found in shallow water at the mud at the waters edge, it can also survive in deeper water. But these plants fail to flower and seed. Those in shallow water flower and fruit easily, the flowerheads can just be seen in the picture opposite. The seeds once produced are able to lie dormant for long periods, and its ability to adapt to fluctuating waterlines makes it a very successful plant. It does tend to prefer open habitats but will be found in open stands of other emergent plants.

 

 

    The Common Reed is primarily a lowland species it can create dense stands often covering many acres in size. These stands are so thick as to exclude many other species. It prefers permanently flooded zones and does not do well were fluctuating waterlines are present. Often associated with eutrophic waters with nutrient-rich substrata's, were by its growth it causes siltation and the decaying deposits from old plants peat. The plant normally has a fairly deep rooted rhizome although floating surface mats do occur. During winter the stalks of die back but these are still utilized by the plant to obtain oxygen for the rhizome.

 

 

Cotton Grass ( Eriophorum angustifolium) forms neat clumps of rush-like foliage with erect spikelets having a cotton wool like seed heads. It spreads strongly through rhizomes and prefers acid soil types. Eriophorum latifolium (Broad-leaved Cotton Grass) is very similar but is more tolerent of lime in the soil or water. It is unlikely to expand into the water as it unable to tolerate deeper water.

 

 

Caltha palustris has many names the Marsh marigold being just one. It grows well in boggy areas but will sometimes actually grow within the water. A strong scented plant which blooms freely. Not particularly large growing depending on variety and spreads though seed or root division. Folklaw suggests that the plant has medical abilities in subduing fits.

 

 

Shoreweed is a plant which is easily overlooked by the casual observer, being so small in stature. It prefers waters low in fertility although in has been found growing well in eutrophic waters. Growing on a wide range of substrates it is quite versatile and prefers the draw-down area it can tolerate submersion and has been found growing as deep as 3-4 meters.

 

 

Sometimes called Umbrella Grass Cyperis involucratus, is a quite pretty looking plant and unobtrusive which prefers moist soil to do well. Fairly delicate and is better suited to warmer climates, a close relative of the Papyrus of paper making fame.

 

 

 

Water-cress are plants of wet ground or shallow water, they prefer calcareous water even if this involves poor substrates. There ability to grow terrestrially means they are well suited to waters which may only be intermittently full. Normally they over-winter as small individuals although places such as springs which provide constant temperatures will allow them to continue to grow throughout the winter. It tends to reproduce vegatativly from creeping stems, and stands can become quite extensive. A plant which is commercially produced for the market.

 

 

Water Dock is a species of eutrophic situations it grows in stands of emergent vegetation where they join the open water. It is a deeply rooted plant which is conspicuous by it large erect leaves and can grow to 6 feet plus in height. It is not normally invasive as they are normally found singularly. It is a wind pollinted perennial and an average plant can bear 16,000 fruits with 95% bearing viable seeds.

 

The Purple Loosestrife is a striking plant which is tall and erect with few branches, it tends to grow singularly or in small stands along the margins of water bodies. It is often found growing close to the waters edge but does not normally like moving water nearby. In some regions it has been declared as an invasive introduction and so as such when found should be treated accordingly.

 

 

 

 

Yellow Loosestrife should not be confused as to belonging to the same group as Purple Loosestrife, it belongs to the Primrose family, Primulaceae. It likes wet ground by freshwater, and in the right conditions can be common. It is quite competative during flowering and so during this period is more likely to be noticed. A pretty flowerhead which adds to its attraction and is unlikely to become a pest.