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leaves on the branches through the winter, or at least 

 until a severe frost followed by a thaw brings them 

 down. The buds, leaves, and flowers are all much 

 attacked by gall-forming insects, many different kinds 

 being found on one and the same tree. 



It is not until the oak is from sixty to a hundred years 

 old that good seeds are obtained from it. Oaks will bear 

 acorns earlier than this, but they are apt to be barren. 

 A curious fact is the tendency to produce large numbers of 

 acorns in a given favourable autumn, and then to bear 

 none, or very few, for three or four years or even longer. 

 The twisted, ' gnarled ' character of old oaks is well 

 known, and the remarkably crooked branches are very 

 conspicuous in advanced age and in winter (Plate II.). 

 The bark is also very rugged in the case of ancient trees, 

 the natural inequalities due to fissures, &c., being often 

 supplemented by the formation of ' burrs.' 



A not inconsiderable tendency to variation is shown 

 by the oak, and foresters distinguish two sub-species and 

 several varieties of what we regard (adopting the opinion 

 of English systematic botanists) as the single species 

 Qiierciis Robur. 



Besides forms with less spreading crowns, the species 

 is frequently broken up into two Q. pedunculate^ with 

 the female flowers in rather more lax spikes, and the 

 acorns on short stalks, the leaves sessile or nearly so, 

 and not hairy when young; and Q. sessiliflora, with 

 more crowded sessile female flowers, and leaves on 

 short petioles and apt to be hairy. Other minute 



