Native Plants of England Defined

Here's the answer to my own question about how "native plant" is defined for England:

Plants in Britain can be classified as native, naturalized, alien or cultivated. There are around 35 species of native tree, for example, depending on how certain sub-species are counted. These plants were already here or arrived here naturally - that is, without Man's help - after the last Ice Age, about 11,000 years ago. Britain was still part of mainland Europe and plant species slowly moved north-west into it as the climate improved and the ice retreated northwards. (There were only about 200 species here at end of the Ice Age.)

With the gradual warming of the world's surface, the ice began to melt, raising the seas. Eventually, about 8,000 years ago, the English Channel flooded. This stopped the natural migration of plants from the rest of Europe, one consequence of which is that we have only about half as many native species as France, for instance. (Scientists know this from pollen deposits and fossil remains.) This date is taken as the cut-off point for deciding whether a plant species in native or not. Examples of native trees on the reserve are Ash, English Oak and Field Maple.

Source.

Comments

[Claire Splan]

Susan, thanks for researching this. It's very interesting, but it makes me question even more why we Americans have settled on such a euro-centric definition of the term here in the U.S. Oh, wait a minute--actually, 200+ years of American history answer that question well enough.

[Anthony Cull]

Whilst in Southern Africa recently I was told that whereas the Western Cape Floral region (Fynbos) has 5,800 endemic species out of 8,600 species, Britain only has 20 endemics out of 1500 species of plants.
Is this correct? Anyone out there who can substantiate this?