COB-NUTS AND FILBERTS. 



227 



No exact formula for the treatment of the main branches can be 

 given, as the vigour of the tree is the determining factor; but it 

 will generally be necessary to prune them to about half their length. 

 Thus each year the branch is advanced outward and upward, con- 

 sidering it as a cordon until the desired height is reached, and about 

 six feet is usually considered enough. 



This restrictive method is necessary to produce the largest nuts • 

 but it is quite possible to let them grow naturally, as the Wild Hazel 

 in the woods, merely thinning out a branch here and there where they 

 are crowded. The nuts produced will be smaller, but not so small 

 as might be expected — the difference really being in the length of 

 the husk. A comparison of the nuts of such trees which have grown 

 " wild " and those from severely pruned trees will show this point. 



We have, so far, considered the tree as a group of radiating cordons ; 

 but there is one other point of importance, and that is the strong 

 " wands," or shoots, which will spring up from the centre, as evidence 

 of the tree's wish to grow up in the natural manner. These shoots 

 must be removed in winter, and are broken out by a sharp twist 

 and not cut with a knife, which is apt to make them shoot again yet 

 more strongly ; the damage done to the basal buds by the rending 

 of the wand prevents them from growing up again. 



The tree, when a few years old, will begin to throw up shoots 

 from the roots — " spawn," as it is technically termed — and these must 

 be cut out by digging down to the root and cutting off close to it 

 with a sharp knife. If allowed to remain, a thicket will result, 

 which will compete with the parent tree, and in due time rob it of its 

 nourishment and light. 



When the tree has reached its final shape it will not require much 

 pruning save the breaking out of wands and the removal of any large 

 growths. 



The flowers of nuts are produced on the short, slender " spray " 

 wood, and it is well therefore for beginners to wait until January or 

 February, when catkins are expanded and the female flowers showing 

 as small claret-coloured threads protruding from the buds. This 

 gives an easy indication as to which growths should be left. 



The fertility of nuts depends firstly, of course, on the age and 

 health of the tree, and secondly on the presence of fine and dry weather 

 during the flowering season. Dry frosty weather does no harm, but 

 a constant succession of wet days is a potent cause of crop failure. 



A heavy crop in the preceding year does not seem to affect the 

 chances of next season's, as in many other fruits. The crop of 1917 

 was good, but was followed by an even larger crop in 191 8. No work 

 has yet been done to test the self-sterility or otherwise of Nuts, but, 

 judging from large orchards, one would assume that the commonly 

 grown varieties are quite self-fertile. The common Filbert is notori- 

 ously a poor cropper ; but this may be due first to its small catkin 

 production and to the fact that in many years its flowers expand 

 before the catkins are shedding their pollen. To remedy this, a 



