Approaching May Day, mature oak trees begin to flower. Both male and female flowers form on the same tree, with the male flowers spreading pollen from dangling catkins and the female flowers opening as tiny buds between the leaves and branches. These buds will be what become acorns in autumn, holding within them the potential for a new oak tree.

Oak trees can live for up to one thousand years, although they are classed as ancient from four hundred years upwards. The oak trees in Wistman’s Wood are thought to be over a thousand years old. Oak wood is durable and hard wearing and can be polished to reveal a beautiful pattern of grain. The bark is rich in tannin, making it useful in the leather tanning process, and the harmless oak gall deformities that grow on some branches can be used to make black ink. Certain species of oak will synchronise every four to ten years to produce a phenomenon known as a ‘mast year’ which is a huge crop of acorns following an almost barren year previously. This is a strategy to protect their offspring and increase their chances of reproducing, as the glut of acorns cannot all possibly be consumed by animals.

Often being the tallest point in a landscape, oak trees are susceptible to being struck by lighting, which has led to an association with the Norse god Thor. Amazingly, a healthy oak tree is capable of surviving a direct strike, even with the air around lightning being heated to fifty-four thousand degrees and the electric current using the sap in the tree as a conductor to earth itself. Lighting scars, visible as singed black streaks, are outward signs that an oak tree has been struck, alongside spirals of peeling bark. Despite these wounds, the oak is likely to go on growing and heal much of the damage caused. This ability to heal has been traditionally harnessed in folk medicine by using oak bark to treat inflammation and pain.

May Day is the perfect time to find your local oak trees and get to know them. Oak is often found in rich soil at valley bottoms, but is also relatively common in many parklands, field edges and of course in pockets on Dartmoor. There is real value in taking time out from busy human activities and sitting in stillness and silence with your back resting against the bark of an oak tree, especially an ancient one. Oak has the resilience to commonly live for over six hundred years, reminding us that rest can be the key to longevity. As a keystone species, an oak provides food and habitat for many other species, maintaining a diverse and healthy environment. We have much to learn from the generosity of oaks.

Helen Bruce