Research at Borderlands
Find out more about the Borderlands Research Forest and how research into carbon, water, soils, peatlands, tree species and forest management is helping build more resilient forests for the future.
Overview
Current and historical research trials at Borderlands Research Forest include:
- Climate change mitigation / forest carbon dynamics
- Forest hydrology
- Forest soils: carbon balance, nutrients and atmospheric pollutants
- Intensive forest condition monitoring
- Peatland restoration, bogs and woodlands
- Silviculture: the cultivation and care of woodlands
- Remote sensing
- Tree species, provenance and improvement trials
Climate change mitigation / soil and forest carbon dynamics
Drought resilience: the effects of mixed-species planting as an adaptation strategy, plus effects on mycorrhizal associations
Climate change is expected to increase the frequency and severity of droughts, posing significant challenges for forest ecosystems. Two new trials at Wark Forest, established in 2025 and 2026, are investigating whether increasing the diversity of tree species and associated mycorrhizal fungi may help our future woodlands to adapt to drought conditions, particularly by exploiting deeper-lying soil moisture.
Outputs
EXPLORATION: Mixed species planting for drought adaptation (Centre for Forest Protection, project page)
Shaping UK drought research priorities through co-design (Centre for Forest Protection, news release)
Mixed species planting for drought adaptation (FR Climate Change Hub page)
Forest carbon dynamics
Understanding and quantifying the carbon and greenhouse gas (GHG) balance of the UK’s woodlands and forests is a key part of our programme on Forestry and Climate Change Mitigation.
A long-term study at Harwood Forest measured continuously carbon dioxide, water and energy exchanges with the atmosphere above the canopy of a mature spruce stand and on a clear-felled / restocked site. The recently-concluded trial has quantified the carbon sink created by the mature stand, and the release (source) of atmospheric carbon from the bare-ground site, both peaty gley soils. This work, combined with remote-sensing data and model development is improving our understanding of the carbon balance of forests and helping to predict how carbon-exchanges will alter in the future.
Outputs
Harwood Forest GHG monitoring site. Summary of research and findings (FR project page)
Further information about the role of forestry in climate change mitigation (FR research page)
Greenhouse gases and carbon dynamics of forestry (FR research page)
Carbon Sequestration (FR Climate Change Hub resources page)
Carbon accounting (FR Forestry and climate change mitigation page)
Matthews et al. (2022). Quantifying the sustainable forestry carbon cycle. FR research report
Forest hydrology
The Coalburn Experimental Catchment
A collaborative project between the Forestry Commission, Institute of Hydrology, Environment Agency and Northwest Water Ltd. to provide information on the long-term effects of afforestation on river flows and upland water supplies. The catchment covers 1.5 km2 and is covered with a network of rain-gauges, meteorological stations and a flow gauge at the outlet in order to measure precipitation, discharge and potential evapotranspiration. It was prepared and planted in 1972/73.
Results have shown that ploughing initially increased annual streamflow compared with the original grassland cover, but that mature tree cover substantially decreased annual streamflow. Hydrological data from 55 years of monitoring are publicly-available and may be used for future hydrological data-analysis and modelling.
Outputs
Forestry and Water Resources (FR research page) With links to many case-studies.
Forest Hydrology Research Programme (FR research page)
Forest and water quality (FR research page)
Nisbet (2005). Water Use by Trees. Forestry Commission Information Note 065
Robinson (2015). Coalburn Research Catchment, Hydrological Review 1967-2012. Internal project progress report, Forest Research.
The effects of forestry and other land uses on aquatic carbon transport
Riverine export of carbon from terrestrial environments to surface waters and oceans is a relatively small component of the total terrestrial carbon flux, but it makes an important contribution to the global carbon cycle. Dissolved organic carbon (DOC) supports aquatic ecosystems, but there may also be concerns for drinking water quality.
In order to better understand the effects of woodlands, soil type, hydrology and climate on aquatic carbon transport, FR has set up two paired studies at Kielder Forest i.e. water-sampling points at two forested and two non-forested locations. DOC sensors and flow-monitoring equipment have been installed at all of the sites.
Outputs
Forestry and Water Resources (FR research page) with links to many case-studies.
Forest Hydrology Research Programme (FR research page)
Forest and water quality (FR research page)
Forest soils: carbon balance, nutrients and atmospheric pollutants
Atmospheric pollutants: deposition, processing, availability and recovery trends in forest soils
The presence of the Level II long-term monitoring plots at Coalburn and numerous other sites in the Kielder region have enabled many important studies and widened understanding of how woodlands, their wider ecology and management practices affect soils and soil water in respect of atmospheric pollution, deposition and soil recovery.
Outputs
Vanguelova et al. (2010). Chemical fluxes in time through forest ecosystems in the UK – Soil response to pollution recovery. Environmental Pollution, vol. 158 , pages 1857–1869
Dissolved organic carbon (DOC) and soil carbon. Long-term trends
The presence of the Level II long-term monitoring plots at Coalburn and numerous other sites in the Kielder region have enabled many important studies and widened understanding of how woodlands, their wider ecology and management practices affect soils and soil water in respect of long-term trends in soil carbon, DOC, the water-use efficiency of forest soils, and wider effects on flows.
Outputs
Swain et al. (2010). Carbon stocks and phenolic distributions in peaty gley soils afforested with Sitka spruce. Organic Geochemistry, vol.41, pages 1022–1025
Ground preparation impacts on soil and tree carbon balance
At the Falstone long-term ground-preparation trial, we have recently undertaken an additional study to quantify the long-term soil carbon changes that take place in organo-minerals soils which result from different intensities of cultivation before restocking. This study also measured above-ground tree growth effects, to enable the impact on carbon stocks to be evaluated at ecosystem level.
Initial findings suggest that soil carbon losses from high-intensive ploughing (33%) and medium-intensive trench mounding (5%), relative to no cultivation, are generally in line with current guidance (Forestry Commission, 2021), although losses from low-intensity ripping (23%) are higher than expected.
However, improvements in tree establishment and growth rates in plots subject ground preparation effectively compensated for the losses in soil carbon, giving no overall change in total ecosystem carbon stocks between cultivation and no cultivation methods; the difference being where the carbon is stored, i.e. more permanently in the soil, or in tree biomass (Corbett at al. in draft).
Outputs
Paterson & Mason (1999). Cultivation of Soils for Forestry. Forestry Commission Bulletin 119
Soil sustainability
BioSoil is a demonstration project, part of the programme of the International Cooperative Programme on the Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests). The project is a test for the development of operational soil monitoring at a large scale. Two soil-survey plots were established: at Kershope (Plot 225) and at Falstone (Plot 227). Soil chemical and biodiversity components have been described, in order to establish a common European baseline of forest soils for further environmental research.
Ouputs
Soil sustainability – List of all FR Publications
Soil sustainability – Forest Focus – BioSoil (FR project page)
Integrated forest monitoring (FR research page)
Woodland creation and soil carbon and nutrient dynamics (FR research page)
Spatial variation in forest soils
Forest soils are known to be highly variable within blocks of woodland, which can complicate condition monitoring. At three sites, including the Coalburn Level II long-term forest condition monitoring plot, a study was undertaken to explore and quantify this variability, including detailed soil sampling and chemical analyses. The results have enabled recommendations to be made for soil sampling designs to properly account for this variability.
Outputs
Sampling soil in forests: accounting for spatial variation (FR research page)
Whole tree harvesting. Soil effects: nutrient concentrations and sustainability
Following concerns regarding the sustainability of whole-tree harvesting for renewable energy, this study investigated the effects on soil chemistry of removing all of the above-ground biomass compared to traditional stem-only harvesting, followed by fertilising of the next rotation. This study found that, on selected soil types, whole tree harvesting, whilst reducing above-ground tree biomass may actually be beneficial for soil C and N sequestration.
Observations from the national and international monitoring networks represented at Wark Forest (Coalburn site) are improving our understanding of how woodland ecosystems respond to environmental drivers such as air pollution and climate change.
Historical datasets are available for foliar and soil analyses, soil moisture, incremental growth of trees, crown condition, meteorology, atmospheric deposition of pollutants, concentration of pollutants (above and below canopy), ground vegetation, leaf litter-fall, soil chemistry and the growth-uptake of heavy metals.
Outputs
Peatland restoration, bogs and woodlands
Peatland and woodland interactions
The project is investigating the extent of external edge effects caused by woodlands on adjacent peat habitats. We will produce guidance in respect of the unplanted buffer zones widths necessary when creating or replanting woodland. This will help to prevent areas of deeper peat from being affected by lowering of the water-table, drying, subsidence and decomposition. Four areas of bog land around Kielder Forest are currently being studied.
Outputs
Obtaining Evidence for Reviewing Trees and Peat Buffer Distances (FR research page)
Peatland restoration: for greenhouse gas mitigation, hydrology and soil biodiversity
FR, with Forestry England and Natural England, have produced guidance and tools to help make management decisions for deep peat sites where woodland removal to restore open habitat is an option.
We are also currently undertaking a study at Spadeadam Forest to quantify the GHG balance and aquatic carbon fluxes associated with contrasting peatland restoration techniques (bunding/drain-blocking vs. surface reprofiling), following conifer removal.
Outputs
Peatland restoration (FR Forestry and Tree Health Resources / decision tools page)
Remote sensing
Remote-sensing applications for forest management
For many years, FR has used Kielder Forest for the testing and development of airborne LiDAR, field laser-scanning, digital aerial photography and optical satellite systems. We are developing techniques for using these to assess tree height and improve mensuration estimates, update of sub-compartment databases, improving production-forecast estimations, detect wind-damage, and to monitor tree health and plant stresses.
Outputs
Remote Sensing (FR tools and resources page)
ReForeSt: Remote sensing for Forest management and Structural Diversity (FR project page)
Trees Outside Woodland Map (FR tools and resources page)
Crow (2008). Historic environment surveys of woodland using LiDAR. Research report, Forest Research
Silviculture: the cultivation and care of woodlands
Cultivation and ground-preparation for forestry
A Large, long-term field trial, planted in 1980, is studying the effects of different ploughing and drainage techniques, of different planting times, handling techniques and initial spacings on the survival and performance of Sitka spruce on peaty gley soil. The trial has recently been evaluated for the effects on above and below-ground carbon storage.
Outputs
Cultivation of Soils for Forestry (1999) Forestry Commission Bulletin 119
Fertilising in forestry: The effects of nutrition on Sitka spruce planted on shallow peat, deep peat and peaty gley soils
Planted in the 1980s, two trials are studying the long-term effects of the application and rates of fertilisers on the survival and performance of Sitka spruce on different soil types.
Outputs
Nutrition of Sitka Spruce on Upland Restock Sites in Northern Britain (2002). FC Information Note 47
Forest fertilisation in Britain (1991) FC Bulletin 95
Nursing mixtures: diversification of young stands of Sitka spruce through enrichment planting using emerging species
Climatic changes and the increasing number of tree pests and diseases have created a need to diversify forests to increase resilience. This trial was planted in 2016 to test the performance of noble fir, Douglas fir, western red cedar and western hemlock when planted in mixtures of varying proportions, beneath the shelter of an established but relatively young nurse crop of Sitka spruce.
Outputs
Creating mixed species stands (FR Climate Change Adaptation Measures page)
Establishing robust species mixtures. (FR project and publications page)
Kerr et al. (2020). Establishing robust species mixtures. RFS/QJF Technical Paper
Nursing mixtures: larch and pine with Sitka spruce
Planted in 1986, this trial is working to improve our understanding of interspecies interactions and how species mixtures may impact financial returns. ‘Nursing’ mixtures of Japanese larch, lodgepole pine and Scots pine were planted with Sitka spruce in ratios of 1:3, 2:2 and 3:1. Survival, productivity and stem straightness have been assessed. The results, published in 2023, indicate that Sitka spruce can be grown in more diverse mixed forests without causing a reduction in productivity or timber quality.
Outputs
Darroch et al. (2023) Do mixtures improve the productivity and quality of Sitka spruce stands in the uplands? Scottish Forestry, vol.77, pages 36-44
Weed control (chemical): long-term effects
Cultivation and drainage trials established in the 1980s have been re-visited to assess the longer-term effects of early weed control on tree survival, growth, yield and carbon sequestration. Effects were identified as highly site-dependent, but of having the potential to cost-effectively increase the storage of carbon.
Outputs
Stokes & Willoughby (2014). Early weed control can increase long-term growth, yield and carbon sequestration of Sitka spruce stands in Britain. Forestry, vol.87, pages 425-435
Tree species, provenance and improvement trials
Douglas fir: compatibility in mixtures with a range of other conifer species
An investigation of the performance of two-species mixture stands comprising of Douglas fir with grand fir, Norway spruce, western red cedar and Scots pine. Planted in 2022, this trial will assess survival, growth and stand development, helping to validate a species-compatibility scoring system.
Outputs
Creating mixed species stands. FR Climate-Change Hub Adaptation Measures page
Tree species diversity. FR Climate-Change Hub Adaptation Measures page
Forest Development Types. FR Tools & Resources page
Silvicultural systems. FR Tools & Resources page
Hybrid (Lutz) spruce: progeny trials
Extensive reliance on Sitka spruce may present risks in times of changing climate and increasing incidence of pests and diseases. Planted in 1987, this trial is testing the performance of hybrid crossings of Sitka spruce with white spruce. Preliminary findings published in 2018 indicate that hybrid families could be a viable alternative to Sitka spruce and help contribute to more diverse and resilient future forests.
Outputs
Spruces for the future (2021) Forestry & Timber News article (including hybrid spruce)
Establishing robust species mixtures (including hybrid spruce). RFS/QJF technical paper
The breeding of conifer species, FR project page
Breeding and production of conifers (Selected populations), FR project page
Noble fir: provenance trial
Noble fir has been classed as a ‘secondary’ timber species but is believed to have potential for wider use. This trial, planted in 1984, provides evidence for the most suitable choice of seed origins, in order that the species may play a wider role in future British forestry. Preliminary findings were published in 2018. Wood properties in respect of timber potential have also been studied recently, indicating suitability for the whitewood timber market.
Outputs
Kerr & McMinn (2018) Summary of FR Seed Origin Trials on Noble fir. FR research report
Scots pine: Dothistroma, breeding for resistance
Demand for Scots pine seedlings is expected to increase, in order to replant more exotic pine plantations devastated by Dothistroma septosporum. FR is reviving its Scots pine breeding programme, infusing new materials from current ecological, genetics and pathology research, with the objective to deliver genetic gains in both disease-resistance and timber quality/volume. We have recently undertaken controlled pollinations at the Forestry England Scots pine seed orchard at Kershopefoot, which will support this research.
Outputs
Sitka spruce: drought-resilience trials
Climatic changes are expected to lead to an increase in the occurrence and severity of droughts in Britain. Sitka spruce currently accounts for 60% of UK timber production but originates from the Pacific northwest of America and is not adapted to drought conditions. Planted in 1985, this trial is helping to identify a series of heritable traits for drought- tolerance in the British Sitka spruce breeding population, which may subsequently be used to select for more resilient trees.
Ouputs
Identifying proxy measurements for drought tolerance in Sitka spruce (FR project page)
FR Climate Change Hub. Climate Change Risks / Drought
Sitka Spruce: Breeding & Improvement Programme
At the Butterburn (Spadeadam), Blackaburn (Wark) and Bellingburn (North Reservoir) research areas, there are many current and historical trials to investigate the performance of crossings derived from a breeding population of 240 clones of the best-performing Sitka spruce (parent) trees that could be found in Great Britain. Please contact us for more details.
Outputs
Sitka spruce, Breeding and production (FR project page)
Improving stiffness in Sitka spruce (FR project page)
Selection and testing of conifers (FR research programme page)
Benefits of improved Sitka spruce: volume and quality of timber (FC Research Note 003)
FR Tree Breeding Programme (FR project page)
The first 50 years of tree breeding in Britain (FR research report)
Improving wood stiffness in Sitka spruce (FR project page)
Sitka spruced: developing genomic selection in Sitka spruce (FR project page)
Species trials: emerging conifer species
Climatic changes and the increasing number of tree pests and diseases have created a need to diversify forests to increase resilience. This trial was established in 2018 to compare the performance (relative to Sitka spruce) of Macedonian pine, western hemlock, Atlantic cedar, noble fir, giant redwood, coast redwood, Scots pine, maritime pine, Pacific silver fir, Weymouth pine, western red cedar, Leyland cypress, European silver fir, Douglas fir, Serbian spruce, Japanese cedar, grand fir and oriental spruce.
Outputs
Priorities for research on Emerging Species (FR project page)
Provenance variation of emerging species (FR project page)
Species trials: historical multi-species, alternatives to Sitka trials on challenging soil and site conditions
A number of 20th Century trials located in the cool-moist climate of the Kielder region sought to identify potential alternatives to Sitka spruce on poorer, wetter soils. Species identified as possible alternatives and suggested for further testing were aspen, Caucasian spruce, common alder, downy birch, grey alder, hybrid aspen, hybrid larch, Lawson cypress, Leyland cypress, Macedonian pine, Serbian spruce, silver birch and western red cedar. The trials also indicated some potentially beneficial use of species mixtures.
A remaining trial at the North Reservoir Block also includes examples of Japanese and hybrid larch, grand fir, noble fir and Pacific silver fir, Norway spruce, lodgepole pine and Scots pine for demonstration purposes.
Outputs
Alternative Species For Kielder (2010). Short summary of findings and data from several trials, by Dr Bill Mason. Copy available on request.