NOTES AND ABSTRACTS. 



377 



the first season, but this effect disappeared in the second season. Of all materials 

 used, shellac was least injurious. 



3. Avenarius carbolineum and yellow ochre caused so much injury that 

 neither substance should ever be used. 



4. Coal tar is also injurious, but quickly disappears either through absorption 

 or evaporation. 



5. White lead and white zinc caused some injury at the outset, but the 

 wounded tissues recovered quickly, and the injury was not very marked at the 

 end of second season. These two paints are the best of the protective substances 

 used, and of the two white lead is the better. 



6. Nothing is gained, in the treatment of wounds, in waiting several weeks 

 before applying any of the various dressings used in these experiments. 



7. The treatment of peach-tree wounds with any of these substances caused 

 so much injury that it may be said that the peach should never be treated with 

 any of thorn. This probably applies to all stone-fruit trees. 



8. There is nothing to show that it is worth while to treat wounds, large or 

 small, of fruit trees with any of these substances used in the experiments. But 

 in the case of very large wounds it may prove of value to cover with a dressing of 

 white lead. — A . B. 



Fruit Trees, Ringing of. By G. H. Howe (U.S.A. Agr. Exp. Stn., New 

 York, Bull. 391, Dec. 1914, pp. 575-584 ; 1 plate). — The object of ringing is 

 to induce and increase fruitfulness, but it is an operation requiring great care 

 and should only be resorted to when all other means fail. The success of the 

 operation hinges upon the fact that in June and July the greatest activity of 

 the cambium is apparent, and this leads to the rapid formation of new bark: 

 Any attempt at ringing when the growth is dormant or sluggish always results 

 in the death of the tree. 



Experiments were made upon apples, plums, pears, and cherries, and extended 

 over three years. The objects were to determine, if possible, the extent to which 

 fruit trees can be ringed without injury, and in what degree, if any, the operation 

 induces and stimulates fruitfulness. 



The conclusions arrived at were : — 



1. Ringing seems to favour certain organs for a time, but devitalizes others. 



2. The removal of narrow strips of bark is less injurious to plant growth 

 than the removal of wider rings. 



3. Under certain conditions, ringing may induce and increase fruitfulness 

 in apples ; but it rarely has these favourable effects on other fruit trees. 



4. Only young and vigorous apple trees — occasionally, pear and cherry trees — 

 can survive ringing. 



5. Ringing stone-fruit trees is not recommended. Nearly all so treated 

 in the experiments died. 



6. Ringing has no apparent influence upon the size, colour, or maturity of 

 apples. — A. B. 



Fungi (Mushrooms, Harmless and Poisonous). By L. Bourguignon {Rev. Hort. 

 April 16, 1915, pp. 455-7; May 16, pp. 487-92; and July 16, pp. 518-21 ; 3 

 coloured plates and 1 plain). — A series of interesting descriptive articles on 

 edible, poisonous, and deadly fungi of the mushroom type. — C. T. D. 



Fungous Diseases of Insects, The Economic Status of. By R. W. Glaser 

 (Jour. Econ. Entom. vii. p. 473, Dec. 191 4). — A discussion on the possible 

 value of fungi for the extermination of insects and in praise of the use of 

 Entomophthora aulicae, a parasite of the brown-tail moth, which has proved so 

 troublesome an insect in certain parts of the States. Reference is made to the 

 paper by Messrs. Speare and Colley, where details of the mode of cultivation and 

 distribution are given. — F. J. C. 



Gooseberry Mildew, American Experiments on, in Cambridgeshire. By F. T. 



Brooks, F. R. Petherbridge, and G. T. Spinks (Jour. Bd. Agr. xxii. 3 ; June 

 1915). — Experiments were made to ascertain whether some form of spraying or 

 soil treatment on a commercial basis could replace tipping (removal of diseased 

 tips) . Twenty-two plots were treated with various fungicides , including Bordeaux 

 mixture, lime-sulphur solution, formalin, caustic soda, copper sulphate or dilute 

 sulphuric acid, while soil was treated with kainit, sulphate of iron, or basic slag. 



Conclusions reached were that spraying with lime-sulphur or Bordeaux mixture 

 in early spring checks development of disease to some extent but not sufficiently 

 to repay cost of application ; all forms of soil treatment and winter spraying ap- 

 peared valueless in checking disease the following season ; heavy applications 



