Exploring the woods
The woods are my favourite place to wander and explore. I love the way that even though you could be only metres away from a road or housing area, the sounds of civilisation can be nearly completely blocked out, especially in the summer months. But what makes these woodlands thrive? Each part of a natural woodland works together to create a incredible ecosystem that has been doing this for the last 117,000, since the Younger Dryas period (the last ice age) when trees and other vegetation slowly reclaimed the land from the thick sheets of ice.
Broadleaf woodland indeed host incredible ecosystems where multiple layers of animals, plants, trees, fungi and insects interact in a complex, symbiotic circle of life and death. This intricate web of life relies on various interacting habitats, each serving a unique purpose. I will delve into the functioning of the ecosystems in a broadleaf (deciduous) environment examining how individual habitats contribute to their overall balance.
During winter, nutrients are stored underground in the roots of trees and shrubs in the form of glucose, awaiting the arrival of spring. In early March, these nutrients rise through the trees’ bark, especially noticeable in birch trees, that are the first to rise, in the form of glucose. This energy kickstarts the production of buds and leaves through photosynthesis, signalling the forest’s resurgence from its winter dormancy.
While it may appear that the forest has been dormant, it has been actively breaking down nutrients left behind from autumn. The mycelium network has been diligently working along the forest floor, breaking down decaying matter, including dead wood, decaying animals, and returning nutrients to the soil. Simultaneously, mycelium produces mushrooms, which not only provides food for foraging animals but also allows it to spread its spores for a new generation. Mycelium is an incredible kingdom that is more closely linked to the animal than the plant kingdom and can spread over vast areas. The largest mycelium network known in the world was found in Oregon USA where the mycelium is believed to cover a total of 2,200 acres, weighs 35,000 tons and estimated to be 8,000 years old. Truly the largest living thing in the world.
Deadwood also plays a crucial role in housing saproxylic (decomposer) insects, where there are over 2000 species in the UK alone, that rely on this habitat. These insects also rely on the mycelium and other microorganisms to break down organic matter into more digestible forms. Examples of such insects include the endangered stag beetle and wood-boring insects like woodlice, as well as hoverflies. Birds, toads, and spiders, among others, in turn, rely on these insects as an important food source.
With the arrival of spring, the woodland springs to life. Hibernating and hidden insects re-emerge as their food becomes abundant and their habitats regain vitality. Woodland flowers such as snowdrops, bluebells, wood anemones, and wild garlic bloom, offering additional sustenance. Caterpillars emerge in April to feed on the newfound leaves, transforming into butterflies to exploit flowering plants like foxgloves. These caterpillars and butterflies in turn become food sources for birds, which return to the ecosystem as part of their migration.
The forest floor becomes carpeted with dog mercury, creating a habitat for ground-nesting birds like woodcocks and serving as a home and food source for various insects. Ants, emerging from hibernation, store food underground, not only sustaining themselves but also enriching the soil with organic matter. As they forage on the forest floor as well as along trees and other plants, ants gather dead or dying insects, leaves, and foliage, further contributing to the nutrient cycle.
The trees, in full photosynthetic mode, convert sunlight into oxygen and nutrients. Flowering shrubs and small trees like dog rose, hawthorn, and elderflower provide a fragrant addition to the woodland that are essential for bees, hoverflies, and moths. Badgers, rabbits, and other hibernating mammals search for food, burying the excess underground. A portion of this buried food ultimately returns nutrients to the soil, sustaining the life for the following year.
Summer arrives, and the tree canopy closes, reducing light reaching the forest floor. Woodland flowers go to seed, and bracken and bramble take over, offering protection for the hidden seedlings underneath. Ferns and bracken, which contain toxic compounds, deter many mammals, preserving these hidden habitats. Bramble provides tasty berries, adding to the food supply. Wood mice and squirrels, concealed by these plants, play a vital role in the dispersal of the seeds.
Early autumn brings rosehips, sloes, damsons, elderberries, and Mirabelle’s, filling hedges and edges with a last food source. Trees like oak, beech, and hazel drop nuts and mast. The majority that are not lucky enough to germinate are either consumed or returned directly as nutrients to the ecosystem. As autumn progresses, the mycelium network resumes its work, breaking down decaying matter. Broadleaf trees, now with reduced photosynthesis abilities due to the decreasing light, shed their leaves, and these fallen leaves become a habitat for insects such as springtails and small gnats. The nutrients such as sugars are stored in the roots which they share with the mycelium in return for other nutrients.
