Voices of Forestry presents analysis and insight from people working all across the forestry sector. This issue, Dr Jo Clark, head of research at Future Trees Trust, makes the case for improving the UK’s broadleaved woodlands – and its future timber supply – through forest genetic resources.

OVER the last decade, we have seen a gradual shift in perceptions of what forestry means to both practitioners and the public. There is an identified need to increase our woodland cover as a tool to help the UK reach net-zero carbon by 2050, as outlined in the Climate Change Act of 2019. To this end, the England Tree Strategy identified a target of 30,000 ha of new planting a year by 2025. 

Because native broadleaved woodlands support greater associated biodiversity than coniferous woodland, new broadleaved woodland is being promoted more strongly in the England Tree Strategy to give the greatest possible biodiversity net gain. Increasingly, diversity of woodlands is seen as a key function of resilience. Diversity often refers to biodiversity (the number of different species) but also includes diversity at the species level – genetic diversity – which is needed to ensure species can survive, adapt and evolve under changing environmental conditions.

READ MORE: Future Trees Trust: Looking to timber's future at Vastern Timber Sawmills

Forests and forestry have never been so much in the public eye and we have a golden opportunity to capitalise on the current trendiness of forestry and the government funding that is available. We can start planting well-thought-through forests that deliver all the benefits that the public want in carbon sequestration and biodiversity net gain, improving the local environment while providing recreational opportunities. But there is also the option to plant for timber, which is overlooked. We should not hide the fact that we need to be planting woodlands for timber production. 

Understanding the role of genetic resources in forestry today is crucial if we are to provide forests and woodlands that will thrive in the future, to supply us with the timber that we need. Productive forests that yield high recoverable volumes of timber will help to store increasing amounts of carbon. The amount of carbon stored will increase not only in parallel with the yield increase expected from breeding programmes, but also with the expected increase in the area planted. Higher growth and productivity also mean less land is required to achieve the same goals. The higher value of the timber from improved seed will also help to encourage new plantations and timber uses that are likely to lock up carbon for long periods. Local timber is more likely to be used if it is of a high quality. Nationally, using home-grown timber reduces dependence on imports and transport (carbon miles). Locally, it makes economies stronger and creates employment and innovation.

When planning for woodland creation, it’s important to consider not only what material we are planting, but also where are we sourcing it from. Future Trees Trust believes passionately in productive broadleaved woodlands that are genetically diverse and adapted to UK growing conditions. Our main aim has been to increase the availability of improved planting material (qualified and tested under forest reproductive material regulations) for productive broadleaved species, both native and non-native. Climate matching research suggests that incorporating some planting stock from 3° south (and possibly as much as 5° south) of a planting site is a sound approach given the uncertain future climate. Sourcing some near-continental material for inclusion in breeding populations therefore seems sensible. Ambitious new planting targets for Britain, coupled with the worrying rise in pests and disease, emphasise the need for home-grown trees from a wide range of species to help the forestry sector meet these targets.

Well-managed and species-rich woodlands offer a great deal to society. In addition to timber production, forests clean the air, filter watercourses and reduce flooding and erosion. They sustain biodiversity, improve mental wellbeing in urban spaces and provide people with opportunities for recreation, education and cultural enrichment. All woodlands offer these benefits, but establishing new woodland with improved planting stock offers many key advantages. Trees get established more quickly, reducing early mortality and the amount of herbicide required. Trees grow more quickly and so rotation times are reduced. Tree form is improved, increasing the volume of recoverable timber that can be used in construction and wood products that lock up carbon for decades. Woodlands established with improved material are more likely to be well managed and deliver all these benefits to society.

So with all these additional benefits of using improved planting stock, why is there not greater uptake of this material? Partly, it is through lack of awareness, but also through lack of understanding. The nurseries do not widely promote this material even though they supply qualified silver birch, sycamore and wild cherry. Qualified oak is in the production pipeline and should be available in the next few years. Mostly foresters planting Sitka spruce today only plant improved material. Let’s make the same progress with improved broadleaves.

DISCLAIMER: Our columns are a platform for writers to express their personal opinions. They do not necessarily represent the views of the writers’ own organisations or of Forestry Journal.