The (relatively) quiet spell between Christmas and New Year gave me time yesterday afternoon for my final wander round Raisby Hill Grassland of the year. Though the weather has been mild for the last couple of weeks and there are new, green leaves aplenty, I only found a single, straggly White dead-nettle in flower – November’s harsh frosts seem to have put paid to this year’s flowers. The mosses I found in profusion at the start of the year are more obvious again now, both on the bare ground of the scree slopes and forming miniature rock gardens on top of some of the limestone boulders strewn around the quarry floor. It’s no secret where the fertiliser for these is coming from (but worth noting that the automatic caption for the picture below was, ‘a pile of broccoli sitting on a rock!)
There is no sign of the Exmoor ponies this month though, if they’ve been moved, it must be fairly recently judging by the hoofmarks on the muddy paths. With the ground mostly bare now, it’s easier to spot wild animal tracks to spot too. There are plenty of obvious deer hoofprints on paths leading to the wooded central part of the reserve.
The fenland area opened up by the removal of accumulated peat in February is now looking more settled and it’s good to see the resultant permanent area of open water being colonised by an aquatic buttercup, probably Ranunculus peltatus, and possibly also brooklime, Veronica beccabunga.
The other main change I can see, visiting this site over the last two or three years, is encroachment of scrubby willow and birch saplings on the scree slopes. This may be a good thing for general biodiversity, as argued very well by Isabella Tree in her book Wilding, but it does pose something of a threat to the habitat of the Dark-red helleborines and other orchids for which the reserve has its SSSI status. A typical trade-off for conservationists!
So what have I learned about Raisby Hill Grassland this year? Walking round the reserve once a month was interesting and much more manageable than my five mile route through Crowtrees LNR last year. Though there are a range of habitats, there are no road verges and the pond areas are fenced off, so I found fewer species than last year – 123 in total. By far the greatest number of species were in flower in July and I found nothing or very little in flower in January, February, November and December. Ruderal road verge species such as dandelions and daisies which flower for much of the year are scarce at Raisby Hill.
I found representatives of at least 30 plant families on the reserve. As last year, the largest number of species found were in the daisy family or Asteraceae, followed by the rose (Roscaceae) and pea (Fabaceae) families.
Brassicas were much less well represented this time, though I did manage to find diminutive Common whitlow-grass for the first time. Like the mosses I saw this month, it was growing on top of limestone boulders, with rabbit droppings for fertiliser acting as a handy scale bar!
The other plant new to me was wild columbine, Aquilegia vulgaris, a deeper purple than its most common garden relatives.
I knew there would be orchids, as I’ve taken part in the Wildlife Trust’s Dark-red helleborine count at Raisby hill in the past but I was not expecting quite the range of species or the abundance I found there this year. The nine species I recorded don’t include any of the hybrids between, for example, marsh and spotted orchids which I’m sure were present.
I enjoyed the butterflies and moths associated with this plant diversity too in June and July, even if I am not much more confident about identifying what I found!
So what about next year’s botanical challenge? For 2020 my plan is to visit a nature reserve I’ve not been to before each month. Durham Wildlife Trust has nearly 40 reserves of various sizes and I have been to only about ten, so that should leave plenty of choice locally. I have a planned trip to the Burren in April and no doubt there will be other opportunities a little further from home too so watch this space! With any luck my first visit, maybe to Trimdon Grange Quarry, will coincide with the BSBI New Year Plant Hunt later this week.