Home-grown hardwoods – Where are we and how did we get here?

When you look at the current UK hardwood situation, you will often encounter some facts that show how little we are using this resource:

These facts often shock people – Why are we not using hardwoods a bit more? Hardwoods are lovely! Let’s try to understand how we got into this situation.

History of hardwood use in the UK

At various times
There were fashions for planting wych-elm, hornbeam, larch […] Often the markets for which these species were chosen had disappeared by the time the trees matured, or with the passing of time, their purpose was forgotten.

A brief history of woodlands in Britain (which makes a very interesting read and where much of the information here comes from)

Woodlands in the UK have been used to supply local crafts and fuel demand since the Neolithic era. Broadleaf woodlands were often managed as coppices (short rotation shoots producing thin stems that regrow from the stump) or coppices with standards (where oak trees were left to mature next to coppiced trees). Oak and sweet chestnut coppices were used for building and ship construction, and oak bark was used for tanning as well. Sweet chestnut was valued for its durability and easy cleaving and was also used for hurdles, fencing and later for hop poles. Hazel was used for weaving and barrel hoops. The highest importance for hardwoods, however, has always been as fuelwood or charcoal for households and industry.

But already from the 17th century home-grown hardwood supplies started to dwindle and structural timber was mostly replaced with imported softwoods. It is this time (1664) when the hypothesis of timber harvesting diminishing forests originates, but even back then this has been untrue in the UK. Forests that were actively managed because they yielded useful products were always regrown, but other uses, namely agriculture, displaced a lot of forest land. At the same time, more or less strategic planting of trees for timber production started, with rather poor success, as the quote above suggests.

The craft of cabinet making had found its way to Britain by the end of the 17th century, and the first wave of the industrialisation allowed the machine-assisted manufacture of furniture. Some homegrown species were used for furniture and other items in Scotland, such as Birch, Sycamore, Willow, Laburnum, Elm, Alder, Ash and even shrubs like Broom and Blackthorn. But even during this time many timber of the same species was imported from Europe and North America, as prices were comparable to the homegrown resource. The furniture industry experienced another rise from the mid-19th century with the possibility of mass manufacture, but often imported timber was used, as the furniture industry was concentrated in London and imported timber was easy to come by and cheap. Beech and other “fashionable” species for furniture making were also planted in England throughout the 18th and 19th century, but many of these trees reached maturity after the decline of the British furniture manufacturing from the early 20th century. Many traditional applications of UK hardwoods were also replaced by new technology (e.g. wire fencing) towards the beginning of the 20th century.

Broadleaf forests started to be more profitable as a source of game than a source of timber and slowly fell out of management. Between the 1920s and the 1990s one use for hardwood (including waste products from processing industries) was pulpwood for papermaking. The majority of pulp, however, has always been imported and the British paper industry has struggled to remain competitive since the 1950s. Since the 1990s, the demand for pulpwood has been mostly replaced by recycled paper, eliminating an important market for by-products of small scale hardwood processors.

During both world wars softwood demand exploded and hardwood demand experienced a revival, which all but depleted the UK’s wood reserves. Afterwards, woodland restoration efforts were focused on productive conifer plantations, to restore timber reserves quickly. The timber industry of the 20th century has therefore mostly focused on the use of softwoods.

Only from the 1980s, when environmental concerns started to rise, broadleaf forests were seen as valuable again – not necessarily for timber production but for their environmental functions and benefits for people. More broadleaves have been planted in the UK since 1985 (after the Forestry Commission’s Broadleaves Policy). In newly established woodland, more broadleaves than conifers were planted most years since 1994 (see also diagrams below). In the 1980s, however, many woodlands were bought by environmental organisations or private owners who opposed active management. Even now more than 90% of broadleaf forest is in private ownership. Owners have an array of different reasons for owning woodland (from producing timber over ecological values to hunting and “it’s just nice to have a woodland”) and might or might not manage their woodland fitting their objectives.

New planting focuses on broadleaves…

…while harvesting and restocking is focused on conifers.

A look into the future

So the UK has been planting more broadleaves and fewer conifers, all the while relying on a steady timber supply from softwoods… something doesn’t add up here. We are still profiting from high planting rates in the 70s and 80s, but softwood availability is estimated to decline from around 2030. At the same time more hardwood timber might become available, and it would be a good idea to plug some gaps that will be left by the lack of softwood with hardwood timber.

The forecast above was made in 2012 and based on the stocked area at that time and the assumption that hardwood would be harvested where there was evidence of thinning activity. But this is only the case for ca. 10% of Great Britain’s broadleaved forests. There is the hope that more private owners would bring their forests back into active management, if this could add some revenue in hardwood products to their business. Also, hardwood can be produced from trees outside forests – even garden and street trees could be used in a variety of applications. It is already becoming evident that the 2012 forecast might underestimate the actual hardwood volumes slightly, but fret not, a new forecast is coming this year!

Hardwood production in GB (average per year) in thousand green tonnes
*The forecast volume is given in thousand cubic metres overbark, which is assumed to be equal to green tonnes

The But…

This all sounds like a great plan – softwood supply reduces, but some more hardwood will be available, nothing changes. Well, it’s not that easy. We need to put some work in now so we will be able to use the growing hardwood resource. Unfortunately, we know very little about the actual properties of UK hardwood species. Some research was done in the 1960s by Gwendoline Lavers, but this data is (a) limited to mostly a few trees per species (b) mostly derived from the testing of small clear specimens (and we don’t know how to relate it to full structural wood properties) and (c) quite old (and the timber properties might have changed since then, as they are influenced by forest conditions and management, which might have changed).

In a new project Building from Englands Woodlands, which is funded under the Forestry Commission’s Timber in Construction Innovation Fund, we will explore the properties of some home-grown hardwoods for building applications. The project is lead by NMITE and focuses on the English resource, since England is where most of the UK’s hardwood grows (see also diagram below). Nevertheless, we are doing similar research on Scottish hardwoods under the SIRT project.

In the three-year project we can only focus on certain species. Of course we want to start with the potentially most relevant ones, so let’s have a look at species availability (which might be one good indicator for relevance, but certainly not the only one). Data for this comes again, from the 2012 availability forecast.

Birch is currently the most stocked species in the UK, and we see there might be quite a bump in birch timber supply in the future. Birch is one of the species that is planted more in Scotland, often to enhance the species diversity of conifer plantations. For all other hardwood species in the UK the largest growing area is England.

The second most available species in this forecast is ash. We will see in the new 2023 forecast how much toll ash dieback has already taken on this prognosis, but it is to be expected that ash supply will reach its maximum in the medium-term, before coming to a stop.

A slow-growing but steady supply of oak and beech and a growing supply of sycamore will probably be most relevant in England in the slightly longer term. But it is also evident that there is a bulk of “other” hardwood that could find its way into a variety of uses. It will take a lot of research and creativity to bring these hardwoods into use!

Do you have an opinion on which species are most important? Let us know!