Oaks of the World, by Harry Baldwin

Harry Baldwin is a Taxonomist and Dendrologist.  He trained and worked at Kew, and has recently become Head of Horticulture at Borde Hill gardens in Sussex.  Harry loved trees from a young age, and his interest in Oaks was inspired by the National Collection of Oaks at Hilliers Gardens.  He visited Grayshott Gardeners in February to share with us his considerable knowledge of this diverse and versatile family of trees.

Oaks have been important for humans since ancient times – many cultures developed with acorns as a staple to their diet.  And their wood has been used for centuries, to build cathedrals, ships and shaft props in the coal mines.

Oak trees are also a key host to other wildlife – ecologists estimate that a single tree can support 2000 species of flora, invertebrates and fungi.

England is blessed with many ancient oaks – more than elsewhere in Europe.  This may well be because our Royal Forests and Deer Parks, made fashionable by William the Conqueror, allowed commoners to collect wood, but not to cut the trees, thus preserving them for future generations.  Some of these trees are thought to be about 1000 years old.

There are 430 different species of oaks around the world – with Mexico having the most diverse population.  They produce acorns of many different shapes and sizes – which are dispersed by bears, squirrels, mice and deer.  Their strategy to evade these predators is known as “masting”.  Once every 5-7 years the tree will produce an abundance of acorns – too many for their predators to eat – ensuring some develop into trees.  In the intervening years, their predators go hungry – ensuring that populations are at a low level when the next “mast” year comes along.  So that’s why we spend some years digging up hundreds of self sown oak saplings, when other years there are very few.

We had a fascinating evening listening and learning about oaks.  Some of us might even have been converted to Quercophiles!