Natural burial sites have marketed themselves based on their interpretation of what natural means to them. This has created a competitive market in which mowing the grass over graves might be seen as acceptable at one site or seen as the very worst ecological activity at another. A similar approach to using native plants might be observed. One site might plant only native trees whilst another is content to plant a variety including Japanese cherry trees. Indeed, some sites start off planting native trees only to find that the bereaved demand favourite trees, like the cherry, and so change their approach.
However, our preference for native planting might be a mistake as regards global warming and resilience. Britain lacks a wide variety of native trees, mostly because we were subjected to numerous glaciations. Even the trees we consider native, such as beech and sycamore, might be seen as introductions. The English oak (Quercus robur), the tree that evolved on our heavy clay soils with regular rainfall, tends to dominate large parts of Britain.
Our limited selection of native trees must now face the resilience challenge. That is, can they survive in hotter, drier summers and wet winters? Can they survive new pests and diseases as the climate warms? If not, our woodlands may begin an irreversible decline. That is particularly true where one tree tends to dominate. In fact, in the British limestone areas, such as the Derbyshire Peak District, where I live, such a scenario is already occurring. The native ash is a tree that dominates our limestone dales and ash die-back, a new disease, is killing them in ever great numbers. This is creating a new landscape and the flora and fauna will also have to change and adapt.
Other native British trees include willow, alder, birch, beech, lime and sycamore. These trees, though, have soil and moisture preferences, and the birch has a short life. Consequently, these trees do not mix easily. For instance, beech do not like clay or wet soils.
As a horticulturalist, I find this a dilemma. In such an abrupt change, I need to review all my experience with trees. My choice of English oak for the first natural burial site at Carlisle in 1990 may be considered a mistake. In cemeteries generally, over 45 years, I planted so many non-native, what we call exotic trees, because these areas were defined and maintained as parkland. Trees were chosen for colour and form even though they were less than perfect for the environment. The Japanese cherry is a classic example, pretty but short-lived blossom and very poor for insects and birds. I could add exotics such as Turkey oak, red oak, cedars, sweet chestnut, walnut, plane, laburnum, maple and many conifers. Now, because we need trees, firstly, to survive higher temperatures in order to lock up carbon, we need to reconsider non-native species.
As a horticulturalist, I lack the skills for this new approach. However, does an ecologist understand the cemetery parkland setting either? And it is not just cemeteries any longer because it also applies to crematoria and even to parks. We need ecology, horticultural and global warming skill sets to define how to move forward.
Although it might sound easy to choose another kind of, say, oak tree, in horticultural terms, all trees vary in form. In other words, they often grow to look very different over time. The English oak has many relatives across the world and includes the Holm oak (Quercus ilex). This tree already exists as an exotic in many cemeteries, parks and coastal areas, where it tolerates salt winds. Coming from the western Mediterranean, one would assume it to tolerate rising temperatures. However, it is an evergreen, dark tree, and apart from its oily acorns, supports little fauna other than grey squirrels and jays. Many horticulturalists would consider it ugly and lacking all the character of our native oak. Yet, in parts of Spain, it is their native tree. If I created a natural burial site using Holm Oak, it would lock up carbon and yet create an environment entirely different to what we might consider as an oak woodland. For certain, we could walk under the trees but there would be no wildflowers growing beneath, just a mass of tree trunks and dense shade. The leaves of this tree, with very high levels of tannin, take decades to decompose and so litter the ground. Deer and hedgehogs would find this a very hostile environment.
The English oak has created our archetypal British woodland, with bluebells and so many other wildflowers growing beneath. It is an ecology we recognise and love. We can leave the trees and bluebells to do their own thing and they need no mowing and very little maintenance. That is why, when I created the world’s first natural burial site, I planted only English oak. I am now having to accept that my vision then, which was before climate change was confirmed, needs to be reconsidered. All those oak trees could be doomed in a matter of a few decades.
Unlike the English oak and bluebells, the exotic alternative trees have left their ecology back in the area where they were the native tree. Nobody has suggested that we transfer that ecology, the actual plants that live in partnership with the tree in its home range. That would be the logical way as those plants must also be susceptible to global warming. However, that would potentially threaten all our existing ecology.
Can the plant scientists create clones of our native trees so that they are genetically more varied and less susceptible to changing seasons, summer drought and excessive winter rain? Trees that tolerate changing climate and potential disease and yet support the ecology we recognise? Let us live in hope. If so, I might see the sapling but only our children will see the tree.
Article by Ken West
Article published in farewells Edition 14
