In article ,
Helen Deborah Vecht wrote:

"La Puce" typed



wrote:
I have a lot of ordinary blackberries with roundish leaves in my
garden. I also have a blackberry plant with very thorny darkgreen
leaves. Its leaves is just like hawthorn leaves and the berries is just
starting to ripe. Teast and look just like blackberries. Any idea what
this plant is please?

You have there two varieties of blackberries, the thornless one,
cultivated blackberries and the wild one, the bramble one The wild one
has usually smaller fruits but more flavour and has vicious leaves!.
Also they ripe now whereas the thornless, at least mine, I have been
picking since end of July (like rasberries). Do pick the wild
blackberries before the 10th October. Passed that date it is said that
they taste awfull because the devil has peed on them )

I thought it was the 1st October!

The berries of whatever grows wild here are big and juicy.
They have mostly finished.

Some have thorny leaves.

Good luck on this one. The rubus family are notoriously difficult
to identify. In addition to species, they seem to have subspecies
and of course humans introduce cultivars and they probably hybridise
when left to their own devices.
You need a batologist apparently.

Perhaps the best-known British batologist (meaning "someone who
studies brambles") was Charles Cardale Babington, Cambridge Professor of
Botany from 1861 to 1896, who published The British Rubi:*An Attempt to
Discriminate the Species of Rubus known to inhabit the British Isles in
1869. http://www.oedilf.com/db/Lim.php?Quote=41976&Popup=1

You might find the "Atlas of British and Irish Brambles" useful
http://www.summerfieldbooks.com/showdetails.asp?id=248