Hareshaw Linn, with its beautiful waterfall and steep-sided wooded banks, is an interesting place to visit whatever the season. Its flora, comprising many ferns and ancient-woodland indicator species, is distinctive and broadly representative of Northumberland’s upland gorges.
Please note that this page and other site features are a work in progress. More plants will be added as they are photographed.
Ferns & Horsetails
Lobed Maidenhair Spleenwort
Asplenium trichomanes subsp. pachyrachis
Asplenium trichomanes subsp. pachyrachis, a rare subspecies of Maidenhair Spleenwort, is a small fern of rocky, calcareous habitats, confined to just a few places in the UK. It is identified by its dark, wiry stipe and rachis, bearing rows of small, rounded pinnules with noticably scalloped margins.
This is the rarest of the three Maidenhair Spleenwort subspecies found in the UK and is restricted entirely to a few areas of limestone rock, Hareshaw Linn being one of them. It is easy to spot close to the site’s waterfall.
Beech Fern
Phegopteris connectilis
A delicate fern of damp, shaded woodland and upland habitats. It is recognised by its soft, triangular fronds, with the lowest pair of pinnae spreading outwards and slightly downwards. Often forming loose colonies, it favours moist, acidic soils and is a characteristic species of undisturbed woodland, often in the uplands.
Oak Fern
Gymnocarpium dryopteris
Oak Fern is a light and delicate fern of damp, shaded woodland and upland habitats. It is identified by its pale green, triangular fronds, divided into three main parts, giving it a soft and airy appearance. Often forming loose patches on moist, acidic soils, it is a characteristic species of cool, shaded, upland environments.
Green Spleenwort
Asplenium viride
A small fern of rocky, often calcareous habitats, including cliffs, screes and limestone outcrops. It is readily identified by its bright green rachis, which distinguishes it from similar species with darker stems. The short fronds bear rounded pinnules, and the plant typically grows in crevices in exposed but sheltered rock faces.
Brittle Bladder-fern
Cystopteris fragilis
Brittle bladder-fern is a delicate fern of rocky habitats, walls and shaded crevices. It is identified by its finely divided, lacy fronds and its fragile stems, which break easily when handled. The small, rounded sori on the underside of the fronds are covered by bladder-like indusia, giving the species its common name.
Polypody
Polypodium vulgare
A familiar fern of rocks, walls, tree trunks and woodland banks, recognised by its leathery, pinnate fronds with rounded lobes and the neat rows of circular sori on the underside. Often growing in mossy crevices or on old stonework, it is a widespread and rather prominent plant at this site.
Hard Shield-fern
Polystichum aculeatum
Hard shield-fern is a robust evergreen fern of woodland, hedgebanks and rocky slopes. It is identified by its dark green, glossy fronds with stiff, sharply pointed pinnules that give the plant a rigid appearance.
Separating this one from Soft Shield-fern can be tricky, but look for the Hard Shield-fern’s stiff, leathery texture and sessile pinnules (lacking a distinct stalk). Soft Shield-fern has a soft, limp feel and an abruptly ending (truncate) frond base, and distinctly stalked pinnules.
Lemon-scented Fern
Oreopteris limbosperma
A graceful fern of damp heaths, moorland and open woodland. It is recognised by its soft, pale green fronds and the fresh lemon scent released when the foliage is crushed. The fronds are broadly triangular, and the sori are arranged close to the margins on the underside.
Narrow Buckler-fern
Dryopteris carthusiana
Narrow Buckler-fern is a delicate fern of damp woodland, flushes and wet heaths. It is identified by its narrowly triangular fronds with finely divided pinnules, giving the plant a light and feathery appearance, and can be separated from Broad Buckler-fern by its straw-coloured scales that lack a dark central stripe.
Borrer’s Male-fern
Dryopteris borreri
Dryopteris borreri is the commonest member of the Dryopteris affinis complex and is distinguished by its soft-textured, semi-deciduous fronds that typically end in an abruptly squared-off base.
Other key features include its flat-topped pinnules with prominent “cat’s ear” teeth on the outer corners, fully stalked basal pinnules, and diffuse veins that frequently show pale blotching in the surrounding leaf tissue
Broad Buckler-fern
Dryopteris dilatata
In damp woodland and along shaded banks, Dryopteris dilatata is one of the more conspicuous ferns. The large, broadly triangular fronds arise in dense clumps and are finely divided into many small segments. The scales covering the stipe (stem) are brown with a dark central stripe, separating them from Narrow Buckler-fern.
Hart’s-tongue
Asplenium scolopendrium
Hart’s-tongue stands apart from most British ferns in having long, undivided fronds rather than divided leaflets. The glossy, strap-shaped leaves form dense clumps on shaded banks, damp woodland floors and old walls. Beneath the fronds, the sori appear as paired, diagonal lines, a distinctive feature of the Asplenium.
Hard Fern
Blechnum spicant
Hard Fern [left] is a distinctive evergreen fern of damp woods, heaths and upland habitats. It forms low rosettes of spreading sterile fronds, from which arise taller, narrower fertile fronds that stand upright in the centre. The pinnae are stiff and evenly spaced, giving the fronds a neat, comb-like appearance.
Lady-fern
Athyrium filix-femina
A graceful and delicate species of damp woodland, stream sides and shaded banks. Its fronds are soft, pale green and finely divided, often arching outward to form loose, airy clumps. The sori are small and curved (J-shaped), helping separate it from most other ferns.
Wood Horsetail
Equisetum sylvaticum
Wood Horsetail is a delicate species of damp woodland, shaded banks and stream sides. Its slender stems bear numerous fine, drooping branches which, unique among horsetails, are branched again, giving a soft, feathery appearance.
Wildflowers
Downy Currant
Ribes spicatum
This rare little shrub is associated with the spate zone of shaded river and streamsides in north-eastern England, Cumbria, and north-eastern Scotland. It looks a lot like the common Red Currant but can be separated based on its mat and rather dull, dark green leaves that are held at right angles to the stem. Helpfully, the petiole or leaf-stalk is he petiole is green in Downy Currant but orange-ish in Red Currant.
Herb-paris
Paris quadrifolia
Herb-paris is a distinctive woodland perennial recognised by its single whorl of four broad leaves set at the top of an upright stem. From the centre arises a solitary greenish flower with narrow sepals and a cluster of prominent yellow stamens. Later in the season, this develops into a single dark blue-black berry, a key feature that makes the species unmistakable
Marsh Hawk’s-beard
Crepis paludosa
Marsh hawk’s-beard is a tall perennial of damp woodland, flushes and stream sides. The bright yellow flower heads are borne in a loose cluster, and the upper leaves clasp the stem with rounded, backwards-pointing auricles. Beneath the flower heads, the involucral bracts carry black glandular hairs, while the fruits are distinctive pale achenes that are ten-ribbed, hairless and lack a beak.
Marsh Hawk’s-beard is most typically found in constantly cool, damp, moist sites, such as near waterfalls, by upland streams, on wet, north-facing cliffs, and in narrow, shady ravines.
Good-King-Henry
Blitum bonus-henricus
An odd one to include here perhaps, but Good-King-Henrey is a prominent feature of the walk towards Hareshaw Linn, occurring in fields close to the carpark.
This one forms clumps of large, triangular to arrow-shaped leaves, often with a slightly mealy surface beneath. The green flowers are small and inconspicuous, produced in dense spikes above the foliage, later developing into clusters of tiny fruits.
Betony
Betonica officinalis
Betony is an attractive perennial of grassland, woodland edges and heathy slopes. It forms a basal rosette of softly hairy, oval leaves with rounded teeth, from which rise square stems typical of the mint family. The bright purple flowers are crowded into a dense terminal spike, making the plant rather conspicuous when in bloom.
Yellow Pimpernel
Lysimachia nemorum
Yellow Pimpernel is a delicate creeping perennial of damp woodland, stream banks and shaded ground. Its slender, often rooting stems spread across the soil, bearing opposite, rounded leaves on long stalks.
The small, bright yellow flowers are borne singly in the leaf axils and look rather lovely in early summer.
Moschatel
Adoxa moschatellina
A small woodland perennial that appears early in spring on damp, shaded woodland floors. It forms patches of soft, deeply divided leaves from creeping rhizomes, often carpeting the ground before the tree canopy closes.
The tiny greenish flowers are arranged in a distinctive cube-like cluster, with four facing sideways and one on top, giving rise to the nickname “town-hall clock”. The flowers are faintly musky-scented, reflected in the species name moschatellina.
Wood Crane’s-bill
Geranium sylvaticum
Wood Crane’s-bill is a tall perennial of damp meadows, woodland edges and upland grassland. The stems carry deeply divided, palmate leaves and relatively large violet-purple flowers with darker veins and a pale centre. The fruits develop into the characteristic long “crane’s-bill” seed head typical of the genus.
Sanicle
Sanicula europaea
A woodland perennial typically found in shaded, base-rich woods and along hedge banks. It forms clumps of glossy, palmately lobed basal leaves from which arise slender stems bearing small, rounded heads of pinkish-white flowers.
Unlike most members of the carrot family, the flowers are arranged in tight umbels rather than open sprays. The fruits are covered in hooked bristles that aid dispersal by attaching to passing animals.
Common Cow-wheat
Melampyrum pratense
Common Cow-wheat is a slender annual of acidic woodland, heaths and moorland edges. Its narrow opposite leaves line the delicate stems, while the pale yellow tubular flowers are borne in the upper leaf axils, often accompanied by reddish-tinged bracts. The species is semi-parasitic, drawing nutrients from the roots of neighbouring plants, particularly grasses and shrubs.
Grasses & Sedges
Wood Melick
Melica uniflora
Melica uniflora is a graceful perennial grass of shaded deciduous woodland and hedge banks. Its slender stems carry a delicate, open panicle of drooping spikelets, each typically containing a single fertile floret. The broad, soft leaves and nodding inflorescence give it a distinctive appearance among woodland grasses.
Remote Sedge
Carex remota
Remote sedge is a slender sedge of damp woodland, shaded stream sides and wet ground. It forms loose tufts of narrow leaves, with thin flowering stems bearing widely spaced spikelets along the upper portion. This well-separated arrangement of spikelets gives the species its name and helps distinguish it from similar woodland sedges.
