15th July 2016
Readers who take an interest in moths or plants will undoubtedly be familiar with the concept of 'aggregates' of species. With moths theses aggregates typically cover two or three very similar species that either cannot be reliably separated from each other, or where to do so would require close examination of a specimen. There are some well-known plant aggregates, but unlike moths they tend to cover large numbers of micro-species. Common examples of plant aggregates include Brambles, Dandelions and Hawkweeds. These groups can be learnt if you put in the time, but the easiest way to find out what species you have is to get a friendly botanist to visit.
I had been wondering for a while what species/microspecies of brambles were present at Whitlingham, so when batologist* Alex Prendergast offered to meet me and have a look at the various plants, I readily agreed. Another fly in the ointment for bramble ID is that they can often only be conclusively identified in summer, usually around July, when they display a complete range of useful characteristics.
We met near the Little Broad, and the first bramble we saw was Rubus conjungens, growing up against the rowing club fence. A little further round we saw the first of many Rubus armeniacus bushes, the largest bramble here. I had previously sent Alex some photos of an interesting low-growing bramble from along the Little Broad shore and in the field he agreed with his initial ID, that it was a hybrid involving Rubus caesius. A bramble with nice pink flowers was R. boreanus and a fourth species nearby was R. boudiccae.
A large bush in the car park was identified as Rubus vestitus. This one was covered with Violet Bramble Rust - perhaps this species of bramble is more susceptible, something that I will look into. We walked along the road down to the start of Whitlingham Woods, before looping back along the Great Broad shore. On this walk we added R. pruinosus, R. adscitus, R. nemoralis and best of all Rubus armipotens. This last species is only known from one other current site in Norfolk, so was a good discovery. Also whilst out I noticed a lot of green leafhoppers, which I identified at home as Cicadella viridis, another new species for the patch. My thanks go to Alex for sharing his knowledge of all things bramble.
* A batologist is someone who studies brambles. Someone who studies bats is a chiropterologist.