Pteridium aquilinum otherwise known as Bracken, is a common fern in many woodlands.  It is a vigorous and resilient species found throughout the UK.  When trees are felled or spaces appear in woodlands, bracken is quick to colonise taking advantage of the increased light. It grows quickly and its fronds can limit the growth of young trees through its dense shading. Similarly at the end of a growing season, the dying fronds can literally smother germinating seedlings and young saplings. Before dying down, bracken can store many materials in its extensive underground rhizome system.  It can tolerate adverse weather and difficult soil conditions  but generally prefers not to be in waterlogged  soils. It is not subject to significant grazing pressure or attack by insect pests or pathogens.  Consequently, it is a highly competitive species, reducing biodiversity.  Some woodland plants can survive in its presence, if they grow in early spring before the emergence of the fronds. [caption id="attachment_5892" align="alignleft" width="240"] A TICK[/caption] Bracken contains metabolites, which when ingested by animals, like cattle, have been linked to cancer of the bladder. It contains a toxin Ptaquiloside and the young leaves when crushed or eaten release hydrogen cyanide. Bracken is also known to harbour ticks, which can spread Lyme Disease. So, it not surprising that bracken is regarded as a weed by managers of woodland, field and pasture; it needs to be controlled, preferably eliminated.  But how to do this is problematic.  A number of strategies have been employed with varying degrees of success.  In woodland, the main objective is to suppress its vigour so that saplings can fully establish themselves . In the past, bracken had a number of uses – for example, as animal bedding which was later composted to give a nutrient-rich mulch.  Also, used for thatching, as a source of potash (pot ash = plant ashes soaked in water in a pot giving a soluble form of potassium K+).  This harvesting of bracken in historical times probably helped limit its spread. However, it is now spreading and its dominance in some areas / habitats is a concern. [caption id="attachment_15642" align="alignleft" width="300"] Rolling bracken[/caption] Bracken can be weakened by the cutting or crushing of the fronds, particularly if this is repeated on a regular basis.  This is both time consuming and expensive. Ploughing the soil, this cuts the underground rhizomes, exposing them on the  surface where they might dry out or freeze.  Ploughing has to be done carefully, as can significantly disturb the soil which can lead to erosion. Pigs can have the same effect as ploughing if the soil is shallow.  Generally these methods are now used. Other techniques included the burning of leaf litter and woody material but this has little effect on reducing the vitality of the bracken, in fact, the release of nutrients from the resulting ash may encourage the growth of the bracken.  Wood chip mulches are similarly ineffective, as are artificial mulches / membranes (difficult to secure them). Herbicides, such as asulam and glyphosate are effective in reducing fronds emerging after its application.  Asulam did little harm to young trees and other plant species, however its use is no longer approved of.  The use of glyphosate is also problematic. It has been suggested that it may be geotoxic & carcinogenic [EFSA 2017 Risk Assessment: Glyphosate]. The UK considered a ban, but as of last year its use was still allowed. Recent work [by Forestry England et al] has revealed an alternative herbicide that may be useful in controlling bracken - namely amidosulfuron. It works by inhibiting enzymes which control amino acid and protein metabolism.  It is thought to have low toxicity to mammals, and is stabile in light. Early trials indicate that it might be suitable for the suppression of bracken in strands of norway spruce, oaks, scots pine, sitka spruce and silver birch. [caption id="attachment_42998" align="aligncenter" width="700"] During the Age of Dinosaurs,  ferns (Polypodiophyta) were among the most abundant ground level vegetation and a significant food source for many herbivorous dinosaurs.[/caption]

The nineteenth century saw the introduction of many ‘exotic’ or non native species.  Some of these introductions have proved to be invasive, for example the Himalayan balsam.  Invasions have also included animals. For example, muntjac, parakeets and grey squirrels.  More recently, there have been many sightings of wallabies. Their presence is thought to be due to escapees from wildlife parks, zoos and possibly private collections. It has been suggested that some were released during the WW2 as people were unable to look after them.  On the Isle of Man, there is a thriving population of red necked wallabies, which dates back to the 1960’s.  A recent survey (2023 & 2024) using thermal imaging and drones estimates the population to be around one thousand animals, possibly more.  The grassy and woodland habitats are not dissimilar to those in Tasmania, though the climate in the Isle of Man is somewhat cooler and wetter.  Here, there are no predators and they seem to have adapted well to the somewhat cooler conditions. They feed on heather, bracken, bilberries and grasses.  The local wildlife trust is concerned that the animals may be having a detrimental effect not only on the native vegetation but also the local fauna - such as ground nesting birds.  On the plus side, there are those who think their presence helps to support the local tourism industry. Beyond the Isle of Man, there have been many sightings of wallabies across the U.K, ranging from Cornwall to Scotland.  Sightings are more common in the South.  In some areas sightings of wallabies are no longer reported as the animals are ‘common place’. The Chilterns being a possible hot spot for sightings.  However, at present it seems that there is little evidence for self sustaining populations though this might change as our climate becomes milder.  There was a small population in the Peak District but it has since died out, possibly due to a harsh winter in 2010.  This population arose from the introduction of five wallabies by a local landowner, Henry Brocklehurst,  the  wallabies formed part of his private zoo at Swythamley. Featured image : thanks to Sandid on PIxabay  

Certain upland areas of the UK , such as Dartmoor, have experienced long term grazing.  This has lead to soil compaction, which in turn means that water run-off is greater. Instead of percolating into the soil, rain water runs over the surface and into rivers. This can lead to flooding during extreme weather events.   Dartmoor (National Park) is a large upland area, which historically was dominated by oak woodland.  Oak woodland now covers a very small area.   The region is now dominated by blanket bog, heathland and acid grassland.  The number of grazing animals (sheep, cattle and ponies - deer) increased significantly between the 1950s and 2000, resulting in soil compaction. Researchers at the University of Plymouth have investigated areas of upland pasture on Dartmoor, and the potential for the establishment of native oak saplings. Working with test sites, they were able to show that significant improvements in soil properties could be observed with 15 years of sapling establishment.   The most effective location (in terms of flood prevention) for sapling / tree planting was on steep hillside on the edge of upland areas.   Their initial work on the planting of woodland has since been expanded to determine the factors that affect the establishment of the tree (oak) saplings.  Their most recent paper notes that the presence of livestock meant that fewer oak saplings survived and those that did were smaller.  However, the effects of cattle and ponies was not always negative in that their trampling could reduce the growth of bracken - allowing more light to reach young tree saplings. [caption id="attachment_34391" align="aligncenter" width="650"] A southern upload moorland - Exmoor[/caption] The research team formulated a number of recommendations relating to the creation / establishment of woodlands in such upland pastures. Livestock should be excluded in areas where there are seedlings and young saplings (1 - 3 years). This exclusion should last for some 12 years. Larger oak (4 - 7 yrs) saplings can be planted into areas of dense vegetation, as this protects the saplings from livestock. Livestock could be allowed to graze in the vicinity of mature oak trees as this would reduce dense, competitive vegetation, allowing seedlings to grow / develop.  Strategic planting and management should be considered  / encouraged for upland slopes where drainage is poor - to allow for soil recovery and development of ecosystem services (flood mitigation). Whilst natural tree colonisation is a low-cost and environmentally sensitive mechanism to promote woodland expansion (working towards government targets on climate mitigation, carbon sequestration etc.), it is likely that the expansion of oak woodland into upland pasture systems will require strategic planting and informed livestock management. [caption id="attachment_37920" align="aligncenter" width="650"] Exmoor Ponies.[/caption] Full details of their paper can be found here : https://besjournals.onlinelibrary.wiley.com/doi/10.1002/2688-8319.12126  (Thanks to Art for images of exmoor and ponies).

In autumn 2016 my wife and I visited a small wood for sale on the edge of the North Yorkshire Moors. We had seen a few other sites but this held more promise as it was part moorland, part regenerating ex-forestry land.  The three things that made it of particularly interest to us were that: it was only twenty minutes away from home; it had a small natural pond; and it had some open space for planting new trees.  As a green person at heart, I often pick up acorns on walks and pop them in a pot.  I was however running short of space and needed somewhere to plant them! Dan, from Woodlands.co.uk, met us on site and explained that the management plan favoured planting oak trees so that made it ideal for us. After a few months of paperwork, we received the key to the padlock of the woodland gate just before Christmas. A nicer present could not have been had. Read more...

What’s so special about heather moorland to beekeepers?  Heather is a small plant known scientifically as Calluna vulgaris, or more commonly ling heather.  As the beekeeping season is winding down elsewhere, the small purple flowers that are a characteristic feature of moorland’s stunning scenery are just opening.  The nectar they produce results in a highly sought after and delicious honey, making it worth all the hard work (both on the part of the bees and the beekeeper) that goes into producing it. Read more...

I recently undertook a Knapsack Sprayer PA1 and PA6a (NPTC) 2 day course. The course is aimed at anyone using, or purchasing pesticides, herbicides or fungicides, and applying them with a knapsack sprayer on land. The courses cover the correct preparation of equipment as well as its maintenance, safe operation and calibration. The course was broken down into the following sections:- Read more...

Much has been written  recent in recent years about the ‘dangers’ posed to our native flora & ecosystems by ‘alien’ invasive species.  Introduced species such Himalayan Balsam (Impatiens glandulifera), Giant Hogweed (Heracleum mantegazzianum), and Rhododendron (Rhododendron ponticum) have been cited as ‘drivers’ of ecosystem change – alongside habitat loss, pollution and over-exploitation. However, voices have been raised to express concern over certain native species that can grow rapidly producing large amount of biomass (or indeed necromass – think bracken dying down in late autumn) and how they may be impacting on our flora, particularly plants of the woodland herb or field layer.  Read more...

A new book on woodlands - Managing your Woodland for Wildlife by David Blakesley and Peter Buckley After 20 years of selling woodlands to people “for enjoyment and conservation” we realised that although the purchasers wanted to do their best for conservation, encouraging biodiversity, protecting endangered species, and just having more birds, bluebells and butterflies, they were sometimes unsure of how best to set about it.  Read more...