‘They have the look of upholsterer’s colour charts, the browns at the tips melting to bronzes and then to the gold-flecked greens of the lower branches. Some sensitive chemical response related to the height, or to changes in temperature or sunlight, or the reach of sap flow is at work. The beeches look busy, flagging up their changes.’
‘Beechcombings, Richard Mabey’
We are lucky enough to live at the foot of a wood which, in the area touching our garden, is predominantly made up of beech. The land rises up behind our plot, so that the wood forms a benevolent overcoat for the house. The surrounding trees create an extra protective layer sheltering the house from harsh winter winds, swathing it in sap and birdsong in the spring, amplifying the breeze in summer. Yet we can be curiously unaware of all this until the autumn. Just at the point we think of sweeping the chimney and gingerly lighting the first fire of the season, our ‘housecoat’ turns all the colours of the fiery hearth, as if to remind us of our primeval need for warmth.
Then begins the slow, floating rain of leaves. The fluttery fabric of the wood falls gently, laying itself out on our driveway as a most magnificent carpet. Clearly, trees do remarkable things at the point of decay, and as Richard Mabey points out, they are far from winding down in the autumn:
‘Leaf fall… provides an opportunity for the tree to get rid of waste products built up over the year, including toxins from the soil. In some cases, the levels of poisonous metals in leaves increases a thousandfold just before they’re shed. At the same time, the tree is breaking down the chlorophyll and and sugars in its leaves and withdrawing them into its woody parts, conserving them. When the green goes, what is left are the brightly coloured carotenoids – orange and brown and yellow antioxidant chemicals… which are believed to bind with toxins. This flurry of chemical activity is stressful for the leaves, and to protect them during the crucial transfer of chlorophyll many trees synthesise yet another anti-oxidant, the bright red anthocyanin. The final mix of these pigments, and tints of specific trees in a particular autumn, depend on factors such as summer sunshine, soil drainage and early frosts.’
While the detoxifying effect of that intoxicating colour is less well known, we all intuitively understand and respond to those transient reds and oranges. Some days, when my raking arm is tired, or when the poet in me is alive, I collect leaves for colour rather than compost – Surely that ephemeral deciduous beauty should not be overshadowed by the bustle and rustles of compost collection. Slowing the pace in our garden is always rewarding, and the simple act of noticing dark red leaves on the ground above our drive led me to the trunk of an ornamental plum I’d barely noticed before. A couple of weeks ago I harvested a whole basket of plum leaves realising that the colour of autumn can be harvested and preserved just like its fruit…