Conservation & Ecology
O
ur natural world, often viewed by the more casual eye as an untidy tangle of vegetation bustling
for a place in the world, is actually a well ordered series of associations. Plants live as ordered communities governed by climate, water availability, nutrients and by the strategies they employ for success. Smaller plants may not choose to associate with larger species, but that’s the order of things. Brought together by processes shaped by natural selection, plant communities or assemblages become ordered into layers which we call structural diversity. Look at the picture of the
bracken. At first glance, the bracken seems to be dominant, overshadowing the lower canopy of bluebell (evident by the developing seed pods). The grass too is relatively thin on the ground. My question here is “how should we manage this area of vegetation?” The uniform answer would be to simply remove and/or eradicate the bracken but, without considering the situation more holistically, any management here could prove deleterious. We may, through the management of the bracken, inadvertently lose the bluebells - the very plants we were perhaps intending to encourage further. The plants within this
assemblage have just not arrived by chance - perhaps they did so millennia ago - but, through natural selection, any plants that could not grow in close association with the bracken would be ousted, either when germinating or at some point through their establishing phase. Natural selection will favour only those species able to grow alongside this dominant fern. Bluebell happens to be a perfect fit. The grass too is also perfectly adapted as it is a woodland species - creeping soft grass - which can slow its rate of respiration and metabolism, capturing light and converting this to energy as and when able to do so and when the dapple of sunlight manages to reach through to the canopy of the floor.
Back to the bluebell. These
plants emerge during spring, before the bracken fronds open. By the time the bracken reforms its canopy, the bluebells have completed their flowering and the bluebell stems are developing the seed pods (visible in the picture). The bracken will then dominate the area until next year, preventing other larger and more competitive perennials to move in and take over. Therefore, if we unwittingly remove the bracken, the plants like bluebell will be lost as taller competitive perennial plants, such as bramble or grass species, will take over.
We also need to be aware of the types of wildlife that may also be impacted by our actions. Bracken is important for our Fritillary butterflies, for adder and as bedding for badger. From this one example, it is clear that any decisions relating to how we manage, be it this small area of bracken or a much larger patch of grassland within the landscape, must be informed through knowledge and experience.
Consider the picture of the oak with the obvious hole in the cut limb. Many a golfer or golfing official would put pressure on the greenkeeper responsible for the maintenance of the course to remove this tree, be it for safety reasons or simply because the tree is perceived to be dying. Natural selection has, for
millennia, brought fungi in close association with trees; it has become the job of the fungi to help trees survive through to old age. Fungi, although to us seemingly parasitic, may have a very specific role; one that, over time, helps to remove the soft inner part of the tree creating, in effect, a tube of outer living wood that will be more resilient to wind throw compared with a more solid trunk.
The majority of the fungi will
not attack the outer band of living vascular tissue that the tree needs to survive. Such processes, rather than proving detrimental, may actually help the longer term survival of the tree. It is, however, always important to view the whole of
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