Sunday 14th May 2017
The Oak Gall Wasp
Whist wondering through woodland or meandering through meadows you may notice woody spherical growths up to an inch in diameter clustered on the young stems of oak trees, especially on English Oaks. If you spot a green gall it will most likely house a gall wasp larvae, however most of the galls you will see are brown and the grown wasps are long gone having burrowed their way out of the galls, looking closely you can most likely see the holes. Alternating generations produce different types of galls on differing species, when not producing their namesake marble shaped galls they produce much smaller galls in the buds of the Turkey oak.
Fun fact: There are over 30 species of oak gall wasps who produce galls in various shapes including discs, ovals and spheres in various sizes. This includes the Oak apple gall wasp which produce spherical galls up to two inches in diameter!
By Tom Cowley – Woodland Supervisor