Writing about Woodland wildflowers as I do, it seems to me that saying a little about hedgerows is quite appropriate. After all a hedgerow is really a very long and very narrow woodland. Of course its lack of width does mean that more light will be available to the wildflowers growing beneath it. However in some situations the available light could be quite similar to that in certain regions of a woodland. Compare the north side of a tall hedge which is aligned east to west with a boundary bank on the south side of a woodland.
Also in my list of woodland wildflowers which I am writing about I have included not just true woodland species but all the shade tolerant species which can be found growing in fairly open woodlands but which are also quite happy in a hedgerow.
There is an excellent book called ‘Hedges’ it is in the New Naturalist series and the authors are E Pollard, M D Hooper and N W Moore. How often do experts have names that link to their field of expertise? Pollard and Hedgerows??? I always think of Gardeners Question Time with Bob Flowerdew and Pipa Greenwood. – you could not make it up if you tried.
Now getting back to the book which as I said is excellent, and it starts off with a poem. I am not a lot into poetry and some wild life books really paste their narrative with poems from here there and everywhere, which I find tedious and rarely read. But this book starts with a poem that I love and would sometimes read to my students if we were doing a day studying Hedgerows or even woodlands. Here it is, its not long …… please read it.
In the Dark and Middle ages,
If we trust to history’s pages
You might search the landscape round,
Not a hedge was to be found.
Instead of little tidy squares,
Mine, and his, and yours, and theirs,
My field, his field, your field, their field,
All formed one enormous bare field.
How they knew without a hedge,
How far any land extended,
Which was middle, which was the edge
Where the whole caboodle ended,
History that tells us so much
About the French wars and the Dutch,
Never says a word to show.
I should also like to know,
In a land of hedge divested,
Where on earth the hedge sparrow nested,
And what did hedgehogs do about it?
Hedge for them meant home and name;
What was their life like without it?
Were they simply -what a shame!
Hogs until their hedges came?
History, that talks so much
Of wars and dates and lists of kings,
And stuffy constitutional things,
Growth of Parliament and such,
Always somehow seems to miss
Interesting points like this.
What a great poem! It was written by R H Charles, though to me I hear it in a sort of Pam Ayres voice. I looked up R H Charles and this is what wikipedia says Robert Henry (R. H.) Charles, FBA (1855–1931) was an Irish biblical scholar and theologian. FBA is Fellow of the British Academy. Whether this is the same person I do not know.
Right back to Hedges.
In fact the poem suggests that hedges were not present in the ‘dark and middle ages’ well not quite right, there may have been less of them, but the original hedge was probably formed by woodland clearance and then leaving a narrow strip of the original woodland between one cleared area and another. These hedges which were originally woodland would of course contain wild flowers which were also originally part of the woodland. Gradually they would of course get infiltrated by other species which we typically think of as hedge row species. Plants like Cow Parsley, Hog weed and Campion.
There are some hedges in Norfolk, just north of Swaffham which contain the woodland wildflower Dog’s Mercury and probably these are examples of remnant woodland hedges.
Still most hedgerows did not arise in this way. There are two ways a hedgerow can be formed. One is obvious and that is to plant a row of trees and bushes. The preferred species were often ones with thorns and prickles as these rendered the hedge more impenetrable. Species like Hawthorn and Blackthorn were often employed but sometimes no doubt a land owner would just uproot shrubs and tree seedlings from the neighborhood and plant these in a row…. thus achieving an instant ancient hedge. More about that in a minute.
The other way a hedge can arise is by erecting a fence, be it made of posts and wire or a wooden fence. Then what happens over time is that birds will sit on the fence and they will eject material, either as bird droppings or as pellets and these may well contain viable seeds from what the bird has been eating. Things like Blackberry seeds, Sloe stones, Rose hip seeds, Hawthorn seeds and so on. These will then germinate directly under or next to the fence and grow up and produce a hedge with the old fence located in the centre. Over time the wooden fence will rot and even the wire will rust and a hundred years on there will be a hedge and no sign of the original fence. Again this will result in a fairly instant ancient hedge.
So what is all this about ancient hedges? Well it is fairly common knowledge that you can tell how old a hedge is by counting the number of woody species growing in it and the more there are the older it is. The thinking behind this is that if a hedge is planted using just one species, say Hawthorn, then over time the original individuals will die and naturally something else will grow in its place, most likely another Hawthorn but possibly a different species. So bit by bit over the centuries the original hedge made up of one species will become more and more diverse.
This has been beefed up a bit and there are various formula to estimate the age of a hedge. This has been based on using old records and maps where a hedge can be fairly accurately aged and then species that are present in it can be counted. As I said there are various formula but the simple version is that you count the number of woody species in a 30 meter section and each different one adds another hundred years to the age. It is all explained in the book on Hedges and there are web sites you can refer to. However as I have indicated above an instant old hedge can easily be produced and might well have been the planted or arisen from a fence at anytime in the last 500 years.