16 CHARTERED FORESTER / CONSERVATION

The escalating biodiversity crisis driven by human overpopulation and overconsumption is intermittently highlighted by major headlines. Sadly, as I write this, breaking news confirms that the

world’s animal population has halved over the last four decades. Similar headlines abound for plants – especially conifers.

The depressing news for this economically and ecologically important group of plants is that 34 per cent of the 615 known conifer species are threatened with extinction1. This is a rise of six per cent over a period of 12 years since the last time all the conifers were fully assessed for threat using the criteria developed by the International Union for Conservation and Nature (IUCN) for threatened species.

The main causes of threat are:•habitat degradation and loss•invasive plant species•human-induced climate change• and, particularly for conifers, over exploitation for timber and non-forest products.

These are all causes where we can have a positive input and, for example, some progress has already been made towards

broadening the genetic base of threatened conifers cultivated in Britain and Ireland. One key aspect to this work has been a strategy that is at the heart of the International Conifer Conservation Programme (ICCP): networking.

Apart from its international activities over the past 20 years in conducting global conifer threat assessments – involving mapping species distributions, conducting field surveys in more than 30 countries and

initiating capacity-building programmes – the ICCP has led an innovative

programme of ‘safe sites’ for the conservation of threatened conifers throughout Britain and Ireland. This is a network of more than 200 dedicated sites where almost 14,000 threatened conifers are being monitored. The sites are mainly on private land, but also take in public

gardens, golf courses and even a monastery. Significantly, they also include Forestry Commission land where the programme has helped to develop two important initiatives – the Bedgebury Conifer Conservation Project based at the Bedgebury National Pinetum, Kent, and the iCONic Project (Internationally Threatened Conifers in our Care), based in Perthshire. Both projects work closely with the ICCP and much of the material used in these sites comes via its

CONIFERS UNDER THREATConifer specialist Martin Gardner, from the Royal Botanic Garden Edinburgh, reports on an important programme to save conifers from extinction

“The depressing news is that 34 per cent of the 615 known conifer species are threatened with extinction”

The monkey puzzle tree is important to the safe site network

WINTER 2014/15 17

collaborative overseas seed-collecting programmes.

One recently developed network comprises a partnership with the City of Edinburgh Council and Greenspace Service, whereby threatened species are being planted in some high-profile council sites, including Princes Street Gardens, Lauriston Castle and Saughton Park.

Many well-known conifer species are listed as threatened and, therefore, play an important role in the network of safe sites listed in Table 1 on page 18. These include the monkey puzzle tree (Araucaria araucana), cedar of Lebanon (Cedrus libani), giant redwood (Sequoiadendron giganteum) and Monterey cypress (Cupressus macrocarpa). Even the widely-planted atlas cedar (Cedrus atlantica), which was not listed in the last

CONIFERS UNDER THREAT

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! Reference:1. Source: Threatened Conifers of the World, the resource compiled by the International Conifer Conservation Programme, Royal Botanic Garden Edinburgh: http://threatenedconifers.rbge.org.uk

The Bedgebury Conifer Conservation ProjectThe ICCP has worked with Bedgebury National Pinetum since 1993, building up its collection of threatened conifers.

The Bedgebury Conifer Conservation Project was launched in 2003. It offers the opportunity to re-evaluate a research area that was originally planted in 1929 as trial plots for a wide range of tree species to test their suitability for forestry.

Many of these plots were destroyed by the great storm of 1987 so, by developing this area as a dedicated site for the conservation of threatened conifers, Bedgebury has moved from trialling trees to saving them.

Today, the 31ha site, which is divided into geographical zones, contains 1,300 newly planted trees. They have been collected from native stands in ten countries by Bedgebury staff who are working in close collaboration with other institutions.

The iCONic ProjectBuilding on the success of Perthshire’s Big Tree Country, the iCONic Project is concerned with planting the next generation of conifers by focusing on some of the world’s most threatened species. It builds on the remarkable legacy of the early Scottish plant collectors, such as Archibald Menzies and David Douglas, both Perthshire men who introduced many of the familiar conifers that have helped to shape the designed landscape of the British Isles.

The project is working in partnership with Forestry Commission Scotland (FCS), Perth & Kinross Countryside Trust and the RBG Edinburgh (through the ICCP) to achieve its aim of planting 10,000 trees over the next ten years. So far, more than 780 trees of 16 threatened species have been planted in sites including the grounds of Scone Palace, Hilton Dunkeld House Hotel, Blair Castle, Gleneagles Hotel and numerous FCS forestry sites.

Endangered giant redwoods

Joint field work between staff of the ICCP, iCONic Project and the Bedgebury Conifer Conservation Project collecting seed from Picea omorika in Bosnia and Herzegovina

The Bedgebury Conifer Conservation Project at the Bedgebury National Pinetum, Kent

TWO UK PROJECTS PROTECTING CONIFERS

18 CHARTERED FORESTER / CONSERVATION

review of the world’s threatened conifers in 1999, has in the last two years jumped from ‘Least Concern’ to ‘Endangered’. Also included is the widely-planted Monterey pine (Pinus radiata), much used across the temperate world in countries such as Chile and New Zealand as plantation species. This species is now ‘Endangered’ in its native California, where it is threatened by fire and harmful fungal pathogens.

Even more at risk is the now widely- grown Wollemi pine (Wollemia nobilis), which was first discovered in 1994 in a remote part of the Wollemi National Park in Australia’s New South Wales. On its discovery, it was immediately placed on the IUCN list as ‘Critically Endangered’, not only due to its small population, but also because of the potential threat of harmful plant pathogens inadvertently being introduced by visiting scientists. The propagation and commercialisation of the Wollemi pine, which saw it being sold across the temperate world, is the most effective ex situ conservation initiative of its kind. If the native population was lost, then the plants now cultivated would provide valuable genetic material for the species to be reintroduced into the wild.

Unfortunately, there are a further 90 conifers species currently listed as ‘Near Threatened’ which could come into the threatened categories in the next few years if the current negative trends identified earlier continue. This list includes the commonly planted Lawson’s cypress (Chamaecyparis lawsoniana), which is threatened by international trade of its timber and the spread of the introduced pathogen Phytophthora lateralis, which limits successful regeneration in many areas.

There are other ways in which threatened conifers can be conserved by ex situ means and, in May 2014, the first planting of the Royal Botanic Garden (RBG) Edinburgh’s conservation yew hedge took

place. Over the next six years, further sections of the hedge will be planted until, eventually, more than 2,000 yew trees surround three sides of the RBG Edinburgh’s Inverleith site. This novel initiative involves using a single species – in this case the common European yew (Taxus baccata) – and will include plants taken as cuttings from a selection of famous heritage trees and seeds of trees from across the natural range of the species.

To date, seed collections have been made from threatened populations in Albania, the Czech Republic, Croatia, Denmark, England, Estonia, Georgia, Hungary, Ireland, Norway, Poland, Portugal, Russia, Sweden and the Ukraine. In effect, RBG Edinburgh will be almost surrounded by one of the world’s most genetically diverse hedge using a single species. Plans are now in place to use other threatened species in a series of hedges within the garden at Edinburgh and the ICCP is encouraging other public gardens to develop their own conservation hedges.

Through its combination of in situ and ex

situ research and conservation activities, the ICCP demonstrates exemplary integrated conservation management, which is the most effective approach to help combat the loss of conifer biodiversity. Broadening the genetic base of threatened conifers grown in cultivation provides a better opportunity to help reinforce depleted native populations and highlights the importance of ex situ conservation in the battle against biodiversity loss.

So, while it is clear that the ICCP’s network of sites is an effective insurance policy against possible biodiversity loss, it also performs another crucial function. It provides the opportunity to highlight the conservation problems that conifers are facing today by means of interpretation and, importantly, through another very significant ‘network’ – that of public awareness and engagement.

Martin Gardner MBE VMM is Co-ordinator of the International Conifer Conservation Programme at the Royal Botanic Garden Edinburgh

Species Country of Origin Threat Category Threat

Araucaria araucana Argentina and Chile Endangered Fire, grazing, invasive plant species

Cedrus atlantica North Africa Endangered Logging, fire and grazing

Cedrus libani Lebanon,Syria, Turkey Vulnerable Fire, urbanisation, grazing, fungal pathogens

Cupressus macrocarpa USA Vulnerable Fire

Metasequoia glytostroboides China Endangered Habitat loss due to land, use changes

Picea breweriana USA Endangered Fire

Picea omorika Bosnia, Herzegovina and Serbia Endangered Fire, poor regeneration

Pinus radiata USA Endangered Fire, grazing, fungal pathogens

Sequoia sempervirens USA Endangered Logging, urbanisation

Sequoiadendron gigantuem USA Endangered Logging, fire

Wollemia nobilis Australia Critically Endangered Small population vulnerable to harmful pathogens

Table 1: Commonly cultivated conifers listed as threatened by IUCN

Fortingall Yew (Taxus baccata), Perthshire

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