Saturday 13 June 2020

Further county resurrections

This is a brief post to share some recent exciting finds of weeds in Oxfordshire. First, Anna Dudley contacted me to tell me about a population of Descurainia sophia (flixweed) that she had found at the M40 services at Waterstock. This plant was last recorded in the county in 2005 and it has always been very rare, really only a casual with us. It is a relatively common arable weed in East Anglia. If you'd like to see it, you will find it in a flower bed at SP62500478.

Surely the find of the season is Oli Pescott's discovery of a large population of Torilis arvensis (spreading hedge parsley) growing in a fallow field in Crowmarsh Gifford. This is an endangered and nationally scarce plant that had been thought to be extinct in Oxfordshire. The field is conveniently located by a footpath that passes a large number of plants at SU6171089298. The field is doubly worth a visit as there is an astonishing display of Centaurea cyanus (cornflower), another endangered arable weed, and very rare now except as an introduction. There is also Euphorbia exigua (dwarf spurge) and Filago vulgaris (common cudweed). Sadly the field is earmarked for development.

Sunday 31 May 2020

English Botanical News and some local news

Tephroseris integrifolia at Aston Upthorpe. Kathy Warden

Cynoglossum germanicum growing at a newly discovered site, on the edge of Russell's Water Common
This is mostly a brief post to advertise the first newsletter of the BSBI's newly formed Committee for England. You can download English Botanical News from here. At a whopping 84 pages, the newsletter discusses much of interest to botanists in England and summarises recent developments from English counties. The objectives of the committee are still very much open to discussion, it having been formed in November 2019, Wales, Scotland and Ireland already having their own committees. Yours truly sits on this new committee, so if there are any (botanical) issues you feel need addressing country-wide then please let me know and I can pass them on. The newsletter includes the minutes of the first committee meeting, so you can see what is already on the table.

With the on-going restrictions on social gatherings, there is not much to report locally, though I am sure people are continuing to find nice things but not telling me.

With some of the restrictions being lifted, the Oxfordshire Flora Group's flora guardians are now able to continue their monitoring work. Kathy Warden has been searching for Tephroseris integrifolia (field fleawort) at its remaining site at Aston Upthorpe Downs in the vice county 22 part of modern Oxfordshire. Sadly it has been missing from v.c.23 for a very long time. It also seems to be much reduced on the Berkshire Downs based on Kathy's findings, but apparently it does not perform well in dry springs.

Fay Banks and I enjoyed a (socially distanced) botanical outing a fortnight ago, taking in Russell's Water, Maidensgrove and the Warburg Reserve. The latter is a honeypot site in the county but both it and the surrounding area had in fact not been well-recorded for Atlas 2020, so we had a lovely sunny walk in a beautiful part of the county, improved recording in this area (although too late for the Atlas project) and saw some great plants. The highlights included lots of the nationally rare Cynoglossum germanicum (green houndstongue) and Carex muricata subsp. muricata (large-fruited prickly-sedge). The former was a conservation introduction to the reserve in the 1990s, and which we found had spread to coppice plots around the reserve and up a lovely green lane to the common at Russell's Water.

Warburg was the original Oxon site for Carex muricata subsp. muricata (or just Carex muricata as some authorities would have it, all five members of the Carex spicata group deserving species status), found there in 2003. It particularly seems to like footpaths and we even found some at a new location a kilometre or so from Warburg, growing by the Chiltern Way footpath. Having spent a bit of time this spring comparing the different members of this locally data deficient group of sedges, it would be interesting to make a post-Atlas project out of them. See below for some comparative photos of four of the five members of the group (respectively, C. spicata, C. divulsa subsp. leersii, C. muricata subsp. muricata and C. muricata subsp. pairae).