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In 2012 various botanical surveys of Lea Marshes were compared. To view this comparison table click this link. | |||||
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A SURVEY OF SELECTED PLANT FAMILIES | |||||
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The flowering plants, ferns and horsetails of Walthamstow Marshes comprise roughly of 350 species and hybrids, covering 60 botanical families. Here is a brief look at just the 15 most important families represented in this area, in order to illustrate the more valuable educational, economical and popular assets of each family, to indicate their relevance to G.C.E. Botany students at both levels, and to show the number of species in each family which grow here.
The Horsetails are living fossils in evolutional decline, being diminutive ancestors of the world-predominant Tree Horsetails of the Carboniferous Age. Three species and a vigorous hybrid are to be found on Walthamstow Marshes. Horsetails produce wind-pollinated cones for spore (not seed) reproduction and it is particularly interesting to demonstrate that these most ancient plants are apparently not eaten by any of our more modern insects which are known to have evolved far more recently. Students of primitive non-flowering plants will also find, at Walthamstow, a few species of lichens, and mosses, and some aquatic algae, awaiting identification.
This is a very important family for human food. Wild Mustards, Horse Radish and various Cresses and Turnips, abound at Walthamstow, along with many smaller, weedier species. 23 species grow here, all with white or yellow 4-petalled flowers.
There are five distinctive buttercup species here. Useful for both O- and A-Level Botany students.
The Chickweeds and Campions play a conspicuous part in the colonisation of disturbed areas, but compete poorly or not at all, with perennials. We have 11 species.
A family of mealy-looking weeds, but some, like Fat-Hen, are as edible as the related spinach. Various Oraches and Goosefoots grow commonly on disturbed soil and sedge peat, comprising seven species in all.
A family of considerable and vital agricultural importance for their nitrogenous properties. 14 species at Walthamstow, mostly Vetches, Trefoils, Clovers, Melilots, etc., growing in perennial grassland. Useful for O-Level students.
Examples occur at Walthamstow of all the British perennial Rosaceous growth forms, as shrubs/bushes/trees (Hawthorn and Blackthorn), thorny climbing shrubs (Roses and Brambles), tall herbs (Meadowsweet), and creeping low herbs (Cinquefoil and Silverweed). An extremely important family for soft fruits and stone fruits, and horticultural trees, shrubs and herbaceous plants. A-Level students.
An important family of about 15 edible and poisonous, distinctive Walthamstow species, including Parsnip, Cow Parsley, Celery, Angelica, Hemlock, Hogweed.
An exceptionally well represented family of nine Polygonums (Knotgrass, Persicaria, Knotweed, Bistort), and a unique Dock community whose current state of evolutionary flux is such that Darwin himself would have been proud to study it.
Poplars, Willows, Sallows, and Osiers are abundantly represented by ten species and hybrids of major botanical, ecological and landscape importance.
The Toadflax, Figwort and Speedwell species illustrate widely varying flower-types for O- and A-Level students. 11 species.
An important family of culinary herbs, and some weeds, including Dead-Nettles, Mints, Woundworts. 11 generally distributed species.
A huge, and very diverse family, including showy displays of Summer and Autumn Thistles, Michaelmas Daisies, Ox-Eye Daisies, Yellow Fleabanes, Ragworts, May-weeds, Hawksbeards, Sowthistles, Burdocks etc. This family has the longest flowering season (except for the grasses), from Dandelion and Coltsfoot in February/March to lingering Yarrows and Knapweeds in November/December. The many large, showy, wild and garden flowers in this family make it popular and easily recognised. The Walthamstow Composites include aliens from the USA, Canada, South America, Europe, the Mediterranean, China and Australia. Nearly 60 species at Walthamstow. O- and A-Level students.
The Sedges (Carex) are characteristic primary marsh and fen species, of which 12 different ones have been recorded from Walthamstow, although some may have gone in recent years. A few are of very local occurrence, though previously much more widespread.
The GRASSES are the largest single plant family in the world, economically the most important, ecologically the most successful, and evolutionally the most advanced. In most years, around 40 species, hybrids, and varieties of grasses may be found at Walthamstow, a truly noble heritage surely unequalled anywhere else so close to Central London. They comprise native and aliens, annuals and perennials, soft and coarse species. Specific grass recognition is a vital to many for ecological studies. Grasses as a whole provide more essential cover and food for birds and insects than any other single plant family, and the grasses include species which flower all the year round. Apart from botanists, ecologists, entomologists, and ornithologists, a thorough knowledge of the grasses is also necessary for all students of agriculture, farming, horticulture, gardening, and the management of parks, playing fields and cemeteries. They may initially be learnt when in flower but identification by the vegetative characteristics alone is also highly desirable during their non-flowering seasons, together with knowledge of their Winter appearances, and survival techniques, wherever these are relevant to the perennial species. A detailed knowledge of this family is, of course, essential for all O- and A-Level Botany students. Grasses make excellent herbarium specimens, lend themselves beautifully to line drawings, and their dried inflorescences are among the most rewarding materials available to flower arrangers, collage artists, and other creative designers, certainly including young children artistically experimenting for the first time. The grass flora of Walthamstow is its most valuable, and its most vulnerable, single feature. | |||||
  
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