Bracken in the Lake District: Pest, Ally, or Both?
- Green Fingers
- May 26
- 22 min read
Introduction
Bracken (Pteridium aquilinum) is one of the world’s most successful and ancient plants, with a fossil record extending back more than 55 million years. It is a native fern that thrives throughout Britain’s uplands and forms extensive stands on hillsides[i]. In the Lake District National Park, bracken covers at least 4% of the land, predominantly on lower fells with deep, well-drained soils[ii]. Its tall fronds create a distinctive rusty-brown blanket each autumn, a familiar feature of the Lakeland landscape. Right now, bracken is appearing fast, and all movement through and across my land is becoming increasingly difficult. I am spending large amounts of time with my battery-driven brush-cutter as I attempt to clear a path through the bracken.
Bracken is a natural component of many habitats and even supports some scarce wildlife. Yet its spread in recent times is widely regarded as a threat to biodiversity, farming, and even cultural sites. This has made bracken a contentious species. Conservationists - that is me – generally support its ecological roles, while farmers and land managers may view it as an invasive weed needing control.
Biodiversity and Habitat Impacts
Ecological Benefits
Despite its weedy reputation, bracken can provide important habitats for certain species in the Lake District. In a mosaic landscape - land that is intermixed with other habitats - patches of bracken contribute shelter and microclimates on which some wildlife depends. For example, bracken stands on warm, south-facing slopes can harbour populations of rare fritillary butterflies. The High Brown Fritillary[iii] and Small Pearl-bordered Fritillary[iv] - two of Britain’s most threatened butterflies - use bracken-dominated areas where violets, their larval foodplant, grow under the bracken litter. The bracken provides these butterflies with a warm, sheltered microhabitat for their caterpillars to develop.
Similarly, ground-nesting birds such as the meadow pipit and skylark often use low bracken cover as nesting sites, which offer concealment from predators. Reptiles also benefit, as the dry carpet of dead bracken creates a warmer microclimate at ground level and helps with thermoregulation for species such as common lizards and adders[v].
In my woodland, where my ongoing attempts to exclude sheep are proving fruitless - Herdwick sheep definitely have the upper hand - bracken can protect certain plants. Bluebells and dog violets are good examples. By deterring grazing, these shade-tolerant plants can persist under bracken as livestock avoids the bitter fronds[vi]. It can also act as a nurse crop, reducing frost exposure and herbivore pressure on young trees or sensitive plants[vii]. A nurse crop is a plant, usually a fast-growing annual grain, that is sown with a slower-growing perennial crop to provide support and protection during its establishment. It acts as a temporary nurse for the main crop, offering benefits such as reduced competition from so-called weeds, erosion control, and protection from excessive sunlight. Overall, where bracken grows in moderation, it can enrich biodiversity by offering cover, nesting material, and warm litter for various insects, birds, and small mammals.
Biodiversity Drawbacks
Unchecked, bracken’s dominance is seen by many as overwhelmingly detrimental to plant and animal diversity. Dense, continuous bracken stands tend to be highly species-poor and can replace the rich mosaic of grasses, heathers, and herbs with a near-monoculture of fern[viii]. The tall fronds, often 1-2m high, form a closed canopy that deeply shades the ground. Few other plants can survive, aside from a sparse spring flora or shade-tolerant mosses. Bracken also produces a thick mat of litter and dead fronds, accumulating on the soil. This physically smothers seedlings and may leach allelopathic chemicals (toxins) into the soil that inhibit the germination of competing plants. The result is a shading of nearly all other ground vegetation over time. Studies have certainly documented that bracken-dominated sites demonstrate considerably fewer flowers than elsewhere, except in rare cases where they harbour relic woodland species in the understorey[ix]. The same applies to the fauna, as there are fewer wildflowers to support pollinators, and less grass or heather for many insects and birds. In the Lake District, this is a serious concern as bracken often invades species-rich meadows, heather moors, and wetlands. While small patches of bracken have ecological benefits, large and continuous bracken expanses tend to homogenise the vegetation and reduce overall biodiversity.
Soil Quality and Carbon Cycling
Soil and Carbon Benefits
Bracken can influence the properties of soil in both positive and negative ways. For example, one clear environmental benefit is bracken’s ability to stabilise soil on steep slopes. That is the situation on my own land. The plant has an extensive underground rhizome network, with creeping root-like stems that can penetrate the ground by more than a metre. Not only does this help bind the soil, but it also reduces erosion and surface runoff, especially where woodland is absent.
Bracken also contributes organic matter to the soil through its annual litter. Every year, bracken’s fronds die back, forming a deep litter layer that slowly decomposes. This builds up soil humus over time and improves soil structure and water-holding capacity. Soil humus is the dark, stable, and highly decomposed organic matter that forms in soil through the breakdown of dead plant and animal matter. It is a crucial component of healthy soil and plays a key role in nutrient cycling, water retention, and soil structure.
In addition, bracken can act as a nutrient pump in some ecosystems. Its deep roots access nutrients - phosphorus, potassium, nitrogen - and, through litter fall and leaching, redistribute these nutrients in the topsoil[x]. Indeed, bracken is often an indicator of fertile, well-drained soil in Cumbria.
Another environmental service provided by bracken is carbon sequestration. This is the process of capturing and storing carbon dioxide (CO2) from the atmosphere, preventing it from contributing to the greenhouse effect. This potentially mitigates climate change. Carbon sequestration can be achieved through natural processes such as plant growth and soil absorption or human-engineered methods such as carbon capture and storage technologies. As with any vigorous vegetation, bracken captures carbon from the atmosphere through photosynthesis and stores it in its biomass and soils. While bracken-dominated soils do not accumulate carbon as deeply as peatlands or woodlands, the total carbon stock tied up in bracken stands is significant. The Lake District National Park Authority has estimated that its bracken stores approximately 79 tonnes of carbon per hectare in the topsoil and biomass. For reference, one tonne of CO2 is equivalent to the electricity consumption of 0.65 average households for a year or driving a petrol-powered car for 8000 kilometres. I am unsure how much bracken I truly possess but I do have 50 hectares of land. That is sufficient space to store 3950 tonnes of CO2, which is the same as 28 million kilometres of driving. Twenty-eight million kilometres? That is 702 times around the world.
Bracken stands should thus not be viewed as biologically sterile. At the very least, they actively participate in nutrient cycling and carbon storage and protect soils from erosion. Bracken is not all bad.
Soil and Water Drawbacks
Bracken can also adversely affect soil quality and nearby water systems. The thick litter layer beneath bracken tends to acidify and impoverish the soil for other plant growth. Decomposition of bracken fronds releases phenolic compounds and other toxins (notably ptaquiloside (PTQ), a bracken carcinogen) into the soil. These substances can inhibit seed germination and root development of neighbouring plants. Even after bracken is removed, residual toxins in the soil can suppress other vegetation for a season or more. Bracken’s impacts on soil carbon are complex. Although it adds organic matter, it may also alter soil microbial communities to store less carbon long-term by promoting faster decomposition. There is some evidence that bracken infestation can reduce soil carbon stocks relative to the heath or woodland it replaced[xi], despite the amount of carbon that bracken is said to store.
Perhaps the most worrying environmental hazard of bracken is the leaching of its toxic chemicals into water. The PTQ that bracken contains is highly soluble and can be washed out of bracken litter and fronds by rainfall[xii]. In areas of high bracken cover and heavy rain, as in the Cumbrian fells, PTQ can run into streams, or leach into groundwater. Studies have detected bracken toxins in soil water below bracken stands and in public water supplies drawn from upland catchments[xiii]. The presence of PTQ in drinking water is a serious concern, as it has been linked to higher rates of gastrointestinal cancers in populations consuming water or milk contaminated with bracken toxins. While water companies monitor and mitigate this risk, it remains an environmental downside of extensive bracken. Additionally, bracken can negatively affect water quality by increasing the tannins in water runoff and staining the water brown.
Landscape Management and Succession
Bracken’s spread poses significant challenges for landscape management in the Lake District. It is a vigorous coloniser of neglected or disturbed land, often thriving where traditional grazing or burning has declined. Bracken is estimated to expand its area by approximately 1-3% per year through rhizome spread under favourable conditions[xiv]. It most readily invades semi-natural habitats such as heathlands, flower-rich grasslands, and even the edges of blanket peat bog. In the UK, the development of blanket bog began around 5000-6000 years ago, as the climate became wetter and warmer. It is generally found over acidic bedrock in places where rainfall exceeds water loss through evaporation and plant transpiration, leading to near-constant saturation. Such conditions favour the growth of bog mosses and cottongrasses, which do not break down when they die but slowly accumulate as peat. Layers of peat create a barrier between the bog vegetation and the groundwater and underlying rock. When fed only by rainwater, the bog becomes increasingly acidic and low in nutrients[xv].
When bracken overhangs a peat bog or heather moor, it can impair the ability of bog or moor to store carbon as well as flood regulation. In addition, the takeover of species-rich grassland by bracken represents a loss of landscape and biodiversity. This is the so-called ferny desert effect. Historically, much of the Lake District’s bracken infestation is linked to woodland clearance and grazing patterns. Bracken readily filled the void when forests were felled on fertile slopes, yet continued grazing pressure prevented succession to new woodland, leaving bracken as the climax vegetation. With grazing now reduced in some areas, bracken can spread even more freely, sometimes forming huge, uninterrupted swathes on hillsides. Some of my land looks like this. There is much work ahead for me.
The pervasive spread of bracken has created a management dilemma. In one respect, farmers seek to reclaim pastures from bracken since it overtakes grazing land and hinders livestock operations. In contrast, ecologists - that is what I call myself - at least conservation ecologists like me, wish to retain some bracken for the sake of the specialised wildlife it supports. This can be a problem. In practice, this means prioritising bracken control in ecologically sensitive or agriculturally important areas while tolerating or even encouraging small patches in areas where rare butterflies or other bracken-dependent species are present.
Traditional control of bracken is laborious. Mechanical cutting or rolling must be repeated multiple times for many years to exhaust the rhizomes. Upland farmers have used techniques such as bracken bashing with tractors or allowing cattle to trample the plant, but these techniques can be complex on steep and rocky fells. The selective herbicide asulam (Asulox) was the most effective means of large-scale bracken suppression for decades. Aerial spraying of asulam each summer could significantly hinder the growth of bracken. However, asulam’s approval in the UK was fully withdrawn in 2023, leaving land managers without a selective chemical option. The concern about asulam was its potential to be an endocrine disruptor, which could interfere with the body's hormones. It was first withdrawn in 2012, although there was an annual emergency authorisation that allowed its continued use until 2023. The Health and Safety Executive (HSE) advised against re-authorising asulam in 2023, and UPL, the India-based, multinational manufacturer, ceased further research for full regulatory approval in October 2023. This effectively made asulam permanently withdrawn in the UK and EU. The only herbicide alternative is glyphosate. Oh dear. This can kill all vegetation and is thus ill-suited for conservation areas and cannot be aerially applied to the Lakeland fells.
Climate change is also an issue. Warmer temperatures and fewer frosts can favour the growth of bracken in upland Britain. The longer growing season that is thus created increases bracken productivity and allows it to encroach at higher altitudes. This means that without intervention, bracken may invade new areas of the Lake District and transform open hill landscapes into dense fern cover.
Beyond ecology and farming, bracken can result in several other issues. For example, Historic England has identified bracken as a primary threat to many scheduled upland monument sites. Bracken can also impede public access. By late summer, head-high bracken can engulf footpaths and deter walkers. Thanks to the dense growth, there is a high risk of picking up ticks in bracken. National Park authorities now issue guidance on tick awareness to hikers, largely because of bracken’s proximity to many Lakeland paths.
Wildfire Risk
Dead bracken dramatically increases the risk of upland wildfires. Every winter, bracken fronds die back, dry out, and carpet Lakeland hillsides with tinder. By late spring, before new green fronds emerge, huge areas of the Lake District are covered with dry bracken litter. This readily ignites. Bracken is considered a key flammable fuel in wildfires and is associated with higher fire intensity and temperature than grass or heather[xvi].
In essence, bracken acts like kindling. Its loose and fibrous fronds catch fire easily and carry flames rapidly across slopes. Fire behaviour research indicates that fires in heavy bracken produce tall flame lengths and can be very difficult to control, especially if wind-driven[xvii]. The Lake District has historically had fewer wildfires than drier parts of England, but climate change and increasing bracken run the risk of changing that. An example was a wildfire on the lower slopes of Blencathra in 2018 that was fuelled by dead bracken and gorse. Bracken-fuelled fires not only threaten property and forests but can also damage peat soils. When the duff layer ignites, it releases large amounts of carbon. The duff layer of peat is the upper, partially decayed organic layer of a forest floor, specifically located above the mineral soil and below the litter layer. Bracken also often grows intermixed with woods or shrubs, so a bracken fire can carry flames into adjacent woodlands.
Traditionally, some have used controlled burning (swaling) of vegetation in the Lake District for land management, but burning bracken is generally discouraged. This is because bracken is thought to be fire-adapted so that occasional burning can encourage bracken by removing its litter and stimulating new growth from rhizomes. Consequently, fire is not a recommended tool for bracken control, and the focus is instead on preventing accidental fires. None of us should forget that approximately 90% of wildfires are started by human activities. These activities include unattended campfires, discarded cigarettes, equipment use and malfunctions, plus intentional arson. Of this 90%, roughly a third are caused by intentional arson. Shame on us all. Meanwhile, natural causes such as lightning account for the remaining percentage of wildfires. Some may feel they have a Right to Roam wherever and however they wish. Let us start by eliminating human-caused wildfires.
Impacts on Agriculture and Livestock
From a farming perspective, bracken does not have much to support it. It competes with pasture, harms livestock, and adds management costs. Bracken invasion reduces the usable grazing area, chokes out grasses and fodder plants, and effectively renders land unproductive for grazing. Hill farmers in the Lake District have long regarded bracken as a weed for this reason. As the fern spreads across the open fell, it prevents the regeneration of nutritious grass and suppresses the mix of heather and bilberry that hardy sheep or cattle might otherwise forage. Bracken can even form impenetrable thickets that physically block livestock movement and make it difficult for a farmer to gather sheep. Stock will generally avoid venturing into tall bracken because of the cover it provides to predators and the obstruction it creates. This effectively shrinks the accessible range for grazing.
Bracken is poisonous to animals if ingested. All parts of the fern contain toxins. Its young fronds (fiddleheads) are especially potent, as they contain high levels of PTQ and thiaminase. This latter enzyme destroys vitamin B1. Livestock usually avoid eating bracken thanks to its bitterness anyway, but in overgrazed or drought conditions, animals can end up by consuming it. Chronic bracken ingestion causes a syndrome in cattle known as bracken poisoning or acute haemorrhagic syndrome. This is characterised by internal bleeding, depression of the bone marrow, and a high incidence of cancers, especially of the bladder or gastrointestinal tract. Thiaminase, as well as causing vitamin B1 deficiency can cause a neurological disorder (bracken staggers) in fell ponies and retinal degeneration (bright blindness) in sheep. Even a relatively small intake of bracken over time can be lethal - as little as 5% bracken in a grazing animal’s diet is enough to cause illness.
There is also evidence of cumulative, carcinogenic effects. Stock exposed to bracken are prone to cancers years later. In the Lake District, farmers historically noticed ill-thrift in young cattle grazed on bracken-covered fells and learned to keep stock away from such areas. Modern veterinary science has confirmed these dangers. For reference, ill-thrift is when an animal's development is slower than expected, often because of a lack of proper nutrition, health issues, or other factors. It is essentially a failure to thrive and can appear as reduced weight gain, poor coat condition, and other signs of poor health.
Bracken stands are a haven for ticks and other parasites that affect livestock. The humid, shaded microclimate under bracken fronds is ideal for the sheep tick (Ixodes ricinus). Tick densities are much higher in bracken litter than in short grass, as the litter provides a warm buffer and plenty of opportunities for ticks to latch onto passing hosts. As a result, sheep that graze bracken-infested land are at greater risk of tick-borne diseases such as louping ill. This viral disease primarily affects sheep, red grouse, cattle, horses, dogs, and humans. The sheep tick transmits it and can cause encephalitis (brain swelling). It has a high mortality rate in sheep and red grouse, particularly when they encounter the virus for the first time.
There is also Lyme disease, again which is carried by ticks. Public health authorities have noted an increase in Lyme disease in northern England, correlating with an expanding tick habitat. Despite this natural worry, Lyme disease is still relatively uncommon in England, with estimates of up to 3000 new cases per year. While official surveillance focuses on laboratory-confirmed cases, it is estimated that many more cases are treated without laboratory confirmation. Many go unreported. To put this in perspective, more than 385,000 new cancers are reported in the UK each year, and in 2022, more than half a million deaths were registered in England and Wales with dementia and Alzheimer’s recorded as leading causes.
Farmers will often treat their sheep with acaricides[xviii] (tick pesticides) more frequently when the animals graze in bracken areas. This clearly adds to management costs. Beyond ticks, bracken can also shelter large numbers of sheep keds and other nuisances. A sheep ked (Melophagus ovinus) is a brown, hairy fly that resembles a tick. It is wingless and about 4-6mm long with a small head. It is a blood-feeding parasite of sheep. Its legs are powerful and tipped with claws, allowing a sheep ked to live its whole life in the wool of sheep. The fact a sheep ked spends its entire life on its host distinguishes it from a true tick, which does not do that. Additionally, sheep keds have six legs, whereas true ticks have eight[xix]. Start counting.
Historical Uses
Bracken was not always seen as a pest by hill farmers. Traditionally, it had several uses in agriculture, which offset its negatives. For example, dried bracken was used as bedding for cattle and horses in winter. Its high bulk and absorbency made it an excellent litter in shippons (cowsheds) and stables. After use, the bracken bedding, enriched with manure, was spread on fields as a fertiliser. If the bracken was burned, its ash is rich in potash, a term used in agriculture to refer to potassium salts, which are essential nutrients for plant growth. The word comes from the process of extracting potash from wood ash, which was done by soaking the wood ash in water, in a pot. Hence the name - potash.
Bracken was also cut and stacked for fuel or burned in pits to produce potash for soap and glass. These traditional uses meant bracken had an agricultural value historically so its spread was constrained by annual harvesting, as it had many other uses. In modern times, these practices have lapsed as synthetic bedding and fertilisers have replaced bracken, and labour-intensive bracken harvesting has ceased. Consequently, bracken has been free to spread, outpacing the dwindling efforts to control it. Today, apart from some niche uses such as a role for garden mulch, or biomass fuel research, bracken’s presence on farmland is almost wholly detrimental. The Lake District’s inscription as a UNESCO World Heritage Site in 2017 highlighted its agropastoral landscapes. Ironically, rampant bracken growth threatens the sheep-grazed scenery such a designation seeks to preserve[xx]. Controlling bracken is thus not only an agricultural necessity but also part of maintaining the traditional landscape of the Lake District.
Medicinal Uses of Bracken
Traditional Applications in the UK
In the UK, bracken has a long history of use in folk medicine. Its rhizomes and fronds were employed to treat many different conditions. For example, decoctions from the roots alleviated stomach cramps, chest pains, internal bleeding, diarrhoea, and colds. Additionally, bracken was used as an anthelminthic to expel intestinal worms, while poultices made from the fronds were applied to sores and burns. In the Lake District, traditional knowledge passed down through generations included bracken in the treatment of rheumatism and arthritis. Steam baths incorporating bracken fronds were said to relieve joint pain, and the plant's diuretic properties were harnessed to treat urinary issues[xxi]. This medicinal use was not unique to the UK and it has been employed in various cultures worldwide. In Finnish traditional medicine, for example, bracken was used to treat stomach problems, gout, and joint pains[xxii].
Pharmacologically Active Compounds
Bracken contains several bioactive compounds that contribute to its medicinal properties. These include flavonoids, phenolic acids, and terpenoids, which exhibit antioxidant, anti-inflammatory, and antimicrobial activities. More specifically, studies have identified compounds such as p-coumaric, p-hydroxybenzoic, caffeic, ferulic, and vanillic acids in bracken, which are known for their antioxidant properties[xxiii]. Furthermore, essential oils extracted from bracken have demonstrated antibacterial activity against several pathogens. Research indicates that these oils contain components such as linalool and carvacrol, which contribute to their antimicrobial effects[xxiv].
Looking at the type of organism against which bracken oils can be effective, it is an impressive list. For bacteria, there is Pseudomonas aeruginosa, Escherichia coli, and Escherichia aerogenes, as well as Bacillus subtilis and Staphylococcus aureus. There are other bacterial pathogens as well. These include Erwinia amylovora, Pectobacterium carotovorum, and Pseudomonas savastanoi pv.savastanoi. Some studies have suggested it may be equally or more effective than streptomycin[xxv]. For fungi, although bracken has not been so extensively studied, bracken fern oil shows some potential against certain fungal infections, including those affecting the toenails and skin. Once again, bracken is not all bad.
Toxicological Concerns
Ptaquiloside and Carcinogenicity
Despite its traditional medicinal uses, bracken poses significant health risks thanks to its content of PTQ, which is carcinogenic. This can induce DNA damage and lead to an increased risk of cancers, especially in the digestive tract. Epidemiological studies have linked the consumption of bracken to higher incidences of gastric and oesophageal cancers in regions where the plant is commonly eaten[xxvi]. While direct consumption of bracken is uncommon in the Lake District, the potential for PTQ to leach into water sources raises concerns about indirect exposure. Studies have detected PTQ in groundwater near bracken-infested areas, indicating a risk of contamination[xxvii].
Thiaminase and Vitamin B1 Deficiency
Bracken also contains thiaminase, an enzyme that degrades thiamine (vitamin B1). Ingestion of bracken can lead to thiamine deficiency, resulting in neurological disorders. This is particularly concerning for livestock that graze on bracken-infested land, as it can lead to conditions such as polioencephalomalacia[xxviii]. This is also known as cerebrocortical necrosis, a neurological disease in ruminants such as cattle, sheep, and goats caused by various factors, including thiamine deficiency, sulphur toxicity, and certain management practices. It is a non-infectious nutritional disorder that affects the brain's grey matter and leads to characteristic neurological signs.
Mythology of Bracken
As one might expect from a plant that has such a depth of history, in addition to so many advantages and disadvantages, it comes with a strong mythology.
Celtic and Christian Traditions
In Celtic folklore, bracken was often associated with mystical properties. In Ireland, it was referred to as "The fern of God," with beliefs that cutting the stem in specific ways would reveal symbols such as the cross or the word "GOD"[xxix].
Supernatural Associations
Bracken was also believed to possess protective qualities against evil. In Scotland, the pattern revealed when slicing a stem was termed the "devil's hoof", while it was also seen as a deterrent against witches and malevolent spirits. Waving a bracken frond was thought to ward off witches, and in some European traditions, crosses made from ferns were used to protect shepherds and their flocks[xxx].
The Myth of Invisibility
One of the most enduring myths associated with bracken is its supposed ability to confer invisibility. This belief likely stems from the plant's reproduction through spores nearly invisible to the naked eye. Folklore suggests that collecting bracken spores on St. John's Eve (23 June) could render a person invisible[xxxi]. In Shakespeare's Henry IV and V, bracken is referenced as a source of invisibility, specifically through its so-called fern-seed. Here is Chamberlain speaking in Henry IV, Part 1[xxxii]:
“Nay, by my faith, I think you are more beholding to the night than to fern seed for your walking invisible.”
The Fern Flower
In Slavic and Baltic traditions, the elusive fern flower is believed to bloom only on Midsummer's Eve. Finding this mythical flower was said to bring fortune and happiness[xxxiii].
Lake District Folklore
The Lake District, with its rich cultural history, has its own set of legends involving bracken. For instance, local tales speak of fairies inhabiting bracken-covered hillsides, with certain areas considered gateways to the fairy realm. There is a thought. Perhaps my land is hiding dozens of fairies. I had best start looking.
Deterring bracken
Bracken thus shows both attributes and disadvantages. The plant is not all about hate, regardless of what a hill farmer might say. This said, I veer more towards the hill farmer as I struggle my way up hill and down dale with shoulder-high bracken around me. I am not small.
I sense the best way forward is to deter bracken, not eliminate it, although I do cut a footpath through the stuff to make it simpler to cross my land. There are several methods to discourage bracken, which do not require manmade materials:
1. Repeated Cutting or Crushing
This is my favourite method. I use an electric brush-cutter, but it would be equally possible to use a bracken roller or scythe. The trick is to crush or cut the bracken fronds at least twice a year, once in mid to late June, and again in late July or early August. Repeated damage exhausts the rhizome’s energy reserves over time, especially if done for 3-5 consecutive years. Crushing is said to be more effective than cutting because it damages more of the stem. I still cut, however, dividing the stem as near the ground as possible. I am unsure how to pull a bracken roller up the steep hillside that forms much of my land.
2. Grazing
Introducing heavy native grazers such as cattle or pigs can sometimes help. There are some Highland cattle that should not be on my land, but on occasion escape from nearby fields. Their presence drives me crazy, but bracken dislikes them, too. These heavy animals trample and disrupt the bracken’s rhizomes and compact the soil, thereby deterring regrowth. Cattle make a mess, and other wildlife gives them a wide berth. Cattle in, wildlife out is a constant Lakeland formula. Meanwhile, sheep - there are plenty in the Lake District despite their declining population - generally avoid bracken and can even worsen the problem by grazing vegetation that might otherwise outcompete the bracken.
3. Encouraging Competitive Vegetation
After cutting bracken, it is possible to sow or encourage vigorous grasses or heather to grow. Heather generally grows from roots, specifically a fibrous root system, rather than rhizomes. While it has some ability to spread vegetatively by layering, this is not the primary method of propagation. There are also bracken-suppressant species such as bramble, gorse, or certain grasses (e.g. Molinia caerulea). Molinia caerulea has the common name purple moor-grass, a species of grass native to Europe, West Asia, and North Africa. It grows in locations from the lowlands up to 2300 m (7546 ft) in the Alps. As with most grasses, it grows best in acid soils, ideally pH values of between 3.5 and 5. However, it can survive under more extreme conditions, sometimes with a pH as low as 2. Molinia caerulea is common on moist heathland, bogs and moorland throughout Great Britain and Ireland while introduced populations exist in parts of North America. Its species name of caerulea means "deep blue" and refers to its purple spikelets[xxxiv]. The grass outcompetes bracken for light and nutrients, especially when the bracken canopy is repeatedly opened up.
I must clearly continue brush-cutting. If nothing else, my washing machine is delighted. Brush-cutting is a messy business as my trousers become splattered with mashed bracken. Don’t forget your goggles, too. Bracken flies everywhere, including into your eyes, should you be distracted for a moment.
4. Shading
I am presently planting as many broadleaf trees as I can, not that I have so far seen much of their effect on the locally invasive spread of my bracken. Broadleaf trees (oak, rowan, birch, etc.) are an excellent secret as bracken loathes deep shade. As and when a closed canopy develops, my bracken should become less competitive.
5. Manual Rhizome Removal
I write this for completeness and no other reason, as manual rhizome removal is extremely hard work. Forget it if you have anything but a small patch of bracken-covered land. If you are an enthusiast for upper torso training, however, the best time to do this is early spring or late autumn, when bracken is dormant. Rhizome removal reduces regrowth, but for me, at least, it is only feasible on a small scale.
The solution? I will continue brush-cutting and planting broadleaf trees. Even then, in moderation. As for my overall thoughts about bracken, I still cannot decide. It has good points and bad ones. I will hover in the middle.
***
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References
[i] The Wildlife Trusts. Bracken. https://www.wildlifetrusts.org/wildlife-explorer/ferns-and-horsetails/bracken#:~:text=Bracken%20forms%20dense%20stands%20in,but%20die%20back%20to%20brown. Accessed 18 May 2025
[ii] Lake District National Park. Farming and carbon. https://www.lakedistrict.gov.uk/caringfor/farming/farming-and-carbon#:~:text=Bracken%20is%20an%20indicator%20of,as%20it%20is%20an%20invasive. Accessed 18 May 2025.
[iii] Butterfly Conservation. High Brown Fritillary. https://butterfly-conservation.org/butterflies/high-brown-fritillary. Accessed 18 May 2025.
[iv] Butterfly Conservation. Small Pearl-bordered Fritillary. https://butterfly-conservation.org/butterflies/small-pearl-bordered-fritillary. Accessed 18 May 2025.
[v] Innovative Farmers. Managing bracken with livestock and associated environmental outcomes. See https://innovativefarmers.org/field-labs/bracken-management/. Accessed 18 May 2025.
[vi] Richard & Chris. Bracken and woodlands. 2 April 2015. See https://www.woodlands.co.uk/blog/flora-and-fauna/bracken-and-woodlands/. Accessed 18 May 2025.
[vii] Fire Effects Information Service. See https://www.fs.usda.gov/database/feis/plants/fern/pteaqu/all.html#:~:text=they%20shade%20the%20smaller%20plants,dense%20western%20brackenfern%20protected%20planted. Accessed 18 May 2025.
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