GALLS 



cylindrical, and consists of about 70 rings. Eggs are found in the buds 

 nearly all the year round. The mites stray about the shoots when the buds 

 shrivel up, and later find their way into the embryonic buds. In January 

 the buds contain adults and eggs, in February the eggs are in abundance, 

 by March there are hundreds of young mites and several adults, and by 

 April there are mites in all stages. In June they may travel from the old 

 buds to the new, and by July there are eggs, young and adults in the 

 young buds, thus continuing the infestation for the next season, and making 

 remedial measures of little avail. Infested bushes should be pruned very 

 hard, and all cuttings burned. The best plan to adopt is to cultivate from 

 clean stock, carefully examining all new bushes, and rejecting any which 

 show any indication of unnaturally swollen buds. 



" Witch-knots," " Witches' Brooms," and " Rooks' Nests " are names 

 given to large bunches of distorted twigs often to be seen on the Birch. 

 They vary in size from a few inches to many feet in circumference. They 

 are caused by a gall-mite {Eriophyes rudis), which lives in the buds, absorbing 

 nourishment, and preventing proper development. The growth of the twig 

 is arrested, and as the new buds appear, they are attacked by the mites and 

 rendered abortive. The mites increase in numbers very rapidly, and when 

 the work of thousands is concentrated at one spot it causes the many twigs 

 to grow outwards in all directions, while the common centre becomes a hard, 

 solid, and woody core. In cases where the mites are distributed along the 

 branches a dense bushy tangle of long and slender twigs is formed. Apparently 

 the presence of these galls does little or no harm to the general growth and 

 development of the tree. Similar growths are caused by a Fungus. 



Eriophyes (Phytoptus) Icevis causes variously-coloured pimple-like galls 

 on the upper surface of the leaves of Alder. They are green, yellow, red, 

 purple, or brown, and may number as many as 400 on a leaf. When 

 numerous they cause the leaf to curl and fold up in a very distorted manner. 



" Nail-galls " on the foliage of Limes are the work of Eriophyes tilice (typicus), 



They are of varying shades of greenish-yellow, red, crimson, purple, and brown^ 



and have the appearance of tacks projecting through the upper surface of 



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