A quick account of an overdue run-in with a Northumbrian speciality – Asplenium x clermontiae

Now, I am rather dreadful at ferns and for a while now have been trying to improve by tracking down our region’s scarcer species. Top of that list for quite a while has been Lady Clermont’s Spleenwort (Asplenium x clermontiae), a hybrid between Wall-rue (Asplenium ruta-muraria) and Maidenhair Spleenwort (Asplenium trichomanes).

Now, this is a rather special fern. Despite its parents being rather widespread and growing together on walls and structures across the UK, it is only known from three sites nationally and only as individual plants. This means that population of this unassuming little plant stands at three individuals nationally, just maybe with a few more out there to be discovered.

Of the sites where Asplenium x clermontiae is known, it is a site in North Northumberland (VC68) that is perhaps the most studied. Indeed, after it was first identified in 2000 by George Swan, it was recorded 20 or so times until 2012 and visited by many more botanists keen to see it. Interestingly, local records held by the BSBI stopped post-2012 though it was reported by Stewart Sexton in this blog post. All of this means that this single little fern hasn’t been reported in almost a decade. Had it gone or was it simply being kept quiet? Today, I went north once again to try and find out, and this time, it appears I was successful!

This was my third attempt at looking for this plant in truth, but I won’t begrudge myself too much – finding a single rare fern among a sea of commoner species is actually quite a challenge. Still, I am glad to finally lay eyes on what is perhaps the scarcest plant I have encountered anywhere in Britain to date. Never a dull day, eh?