An expedition to Falcon Clints

Upper Teesdale is a truly remarkable place, packed with rare and wonderful arctic-alpine plants. Each year, I try to visit at least once and each time manage to discover something new and exciting to make the trip worthwhile. Last week, my annual visit came around again and together with NHSN’s Urban Naturalist, Ellie, I set off in search of a group of species I’d yet to properly explore in this part of the world – ferns!

Of course, before the fern hunting could begin, we had to reach Falcon Clints, a truly stunning gorge nestled below the confluence of Maizebeck and the River Tees. To get there, we first had to cross Cow Green with all its botanical riches (such a chore, I know!). As expected, this leg of the trip was a delight with hundreds of Mountain Pansies Viola lutea now in full bloom. As you can see, these cheerful little plants come in a brilliant range of colours.

Despite the abundance of pansies, one thing that struck us immediately was the near-total absence of Spring Gentians Gentiana verna. They had all gone over, perhaps hastened by the warm weather. Nevermind; what we did find during this stage of the walk more than made up for it. In damper spots, the Bird’s-eye Primroses Primula farinosa were out in force Variegated Horsetail was a particularly nice find in the flushes. Hardly the most inspiring plant, I confess, but I’ve always had a soft spot for it.

Further down the trail, about halfway to Cauldron Snout, more notable species were found. Mountain Everlasting Antennaria dioica was a highlight, and Sea Plantain Plantago maritima was in flower. In the drier, more exposed areas of sugar limestone, we also came across Spring Sandwort Sabulina verna, and grassy patches offered Lesser Clubmoss Selaginella selaginoides, Blue Moor-grass Sesleria caerulea, and countless sedges which we opted to overlook this time.

The initial descent down Cauldron Snout is truly beautiful and well worth a pause, if you’re ever passing. Falcon Clints is equally, if not more, breath-taking with its steep dolerite cliffs fringed by dramatic scree slopes. It’s worth taking a moment to appreciate the gradual shift in vegetation as you scan down the cliff face: moorland heather giving way to stunted trees and herbs, and eventually, to ferns. We even spotted a few Ring Ouzel – always nice to see.

The list of ferns found at Falcon Clints is impressive – if a little daunting – with species ranging from common woodland fare to truly rare plants found pretty much nowhere else in England. Some of the more familiar species we encountered early on included Lady-fern Athyrium filix-femina, Bracken Pteridium aquilinum, Narrow Male-fern Dryopteris cambrensis, Broad Buckler-fern Dryopteris dilatata and Hard-fern Blechnum spicant, but these quickly faded into the background as we began to explore the scree.

The first exciting discovery was the curious-looking Parsley Fern Cryptogramma crispa, a calcifuge pioneer often found on exposed rock and former mine waste. It is a rather lovely plant, as is the next species we came across – Beech Fern Phegopteris connectilis. Now that I think about it, this may be the first time I’ve seen this distinctive little fern outside of damp, humid woodland.

Arguably more exciting, at least for this novice pteridologist, was the presence of several stands of Mountain Male-fern Dryopteris oreades. Though similar in appearance to the ubiquitous Male-fern Dryopteris filix-mas that many of us see regularly, this species is far more particular about where it grows and favours upland slopes and boulder fields. It can be distinguished from its commoner relative by the underside of its fronds where the sori are confined to the lowest portion of the pinnule. If you spot distinctive clumps of ferns adorning a mountainside, it’s well worth taking a closer look.

As we meandered through the valley, it was hard not to be distracted by the trees. Though relatively sparse at Falcon Clints, the ones that do grow here are gnarled, twisted, and strikingly beautiful. Juniper Juniperus communis is easy to find, as are Aspen Populus tremula and Rowan Sorbus aucuparia. Perhaps more intriguing though are the birches and it is worth checking any with noticeably contorted trunks and branches for signs of the upland subspecies of Downy Birch, Betula pubescens subsp. tortuosa. We spotted one along the way though admittedly, we weren’t looking that hard.

While most of Falcon Clints is dry and exposed, there are pockets of deep shade — particularly beneath rocky overhangs. It was in these secluded spots that we searched for our next group of ferns, and before long we were rewarded with some healthy specimens of Green Spleenwort Asplenium viride, a species abundant in this part of the world but rather rare elsewhere. Growing alongside it were Brittle Bladder-fern Cystopteris fragilis and Maidenhair Spleenwort Asplenium trichomanes subsp. quadrivalens. The latter prompted a closer look just in case it turned out to be something rarer but alas, I think not. We also found a solitary Hard Shield-fern Polystichum aculeatum – a common species, yet the only one we encountered all day.

We paused for lunch and eventually decided to turn back roughly 1.5 miles into the valley, right at the point where the path disappears and you have to scramble over rocks to go any further (you’ll know it when you see it). During our break, we took the opportunity to explore a particularly diverse overhang that held more than a few interesting plants. Beneath some willows which we tentatively identified as Dark-leaved Willow Salix myrsinifolia, we found Bird’s-eye Primrose, Marsh Valerian Valeriana dioica, Butterwort Pinguicula vulgaris, and some fine examples of Northern Bedstraw Galium boreale, not yet in flower.

After that, all that remained was to head back the way we came, admittedly rather slowly so to spend as much time as possible in this incredible place. However, there were a few more discoveries to share…

At the start of this post, I mentioned that Falcon Clints is home to some incredibly rare and special ferns. One in particular stands out: Holly-fern Polystichum lonchitis.

This striking fern prefers well-drained, cool and moist conditions at the base of cliffs, typically in stabilised boulder scree. A poor competitor, it avoids densely vegetated areas and is considered vulnerable across much of its native range. It wasn’t a species I had seen before, so you can imagine my delight when, after scrambling up a particularly steep bank, we were rewarded with the specimen shown below. A real thrill, even if it did look a little weather-beaten.

I won’t share precise location details here, but the information is out there if you know where to look.