Woodworkers 



Small wonder then that these gall insects received 

 different scientific names before it was shown that they 

 were merely different generations of one and the same 

 insect. The case of the oak apple is nearly as strange. 

 Long before the winter has left us the little gall-wasp, 

 maker of this well-known gall, is hard at work. She lays 

 her eggs in the end buds of the oak branches, first of all 

 boring a hole and then depositing her eggs therein. 



A well-known entomologist once observed the work of 

 one of these insects. "When it had finished its first bud," 

 he wrote, " it went on, without interruption, to another, and 

 was altogether eighty - seven hours busily employed in 

 laying eggs." In these two buds, five hundred and eighty- 

 two eggs were counted. Early in May the galls begin 

 to grow, and four short weeks later they are fully developed, 

 being soft and of a greenish-yellow colour. As the oak 

 apples grow they turn rose-coloured, and shortly after 

 this change winged males and wingless females bore their 

 respective ways from the galls. These females are smaller 

 than the individuals which produced them their mothers 

 and, after mating, they pass down the trunk of the oak- 

 tree, penetrate the soil and deposit their eggs in the roots, 

 causing hard, brown, spherical galls to be formed. From 

 those galls, pale brown, wingless females emerge ; they 

 push their way through the soil, travel up the trunk, thereby 

 running the gauntlet of tits, nuthatches and tree creepers, 

 ever on the alert for insect fare, till at length they reach 

 the end buds of the tree and, laying their eggs therein, 

 the life cycle begins anew. It is interesting to note that 

 the oak apples which are formed in spring, when the trees 

 are full of sap, are themselves sappy ; the root galls, formed 

 in autumn, when there is little sap in the trees, are quite 

 hard and effectually protect the larvae within from frost, 

 during the long winter months. 



The marble gall of the oak, commonest of all galls and 

 often wrongly called the oak apple, is still a mystery, for 

 nothing but female gall insects have ever been discovered. 



