The common or English oak (Quercus robur) is one of the most widely distributed lowland European trees. Oak trees can reach heights of up to 40 metres, and live for many hundreds of years. The oldest oak tree in Britain is the Bowthorpe Oak in Lincolnshire, which has a huge hollow trunk.
English oak trees are deciduous and the male and female flowers bloom in May. These are followed by distinctive seeds or nuts called acorns in the summer and autumn, a rich food source for many mammals and birds.
How to grow Oak trees
Oak trees are grown from acorns. Following a successful germination a seedling will appear the following spring. Follow the 'Planting acorns' activity to learn how they can be grown in the classroom to demonstrate germination.
The tree requires moist conditions to grow and need to be at an elevation of less than 500 metres. When planting it is vital to remember the length of time the tree will grow in that position and its eventual size. The tree also has a vast deep root system. Oak trees do not produce acorns until they are about 40 years old and they are at their most productive from 80-120 years.
Oak trees proivide a rich habitat for biodiversity. They are important part of woodland foodchains hosting hundreds of species of insect, supplying many British birds and mammals with food. Flower and leaf buds of English Oak provide food for the caterpillars of purple hairstreak butterflies.
The fallen autumn leaves of oak trees break down easily, providing a rich leaf mould for the ground beneath. This supports insects such as the stag beetle as well as many fungi like the milk cap. Holes and crevices in the bark can provide nests for many birds or roosts for several species of bat.