COPPER ACETO-ARSENITE. 273 



orchards only. During the ten years previous, the quantity of apples 

 which without the treatment became wormy was calculated as 50-75 

 per cent of the total crop. It is estimated that the plus value was 4s. 

 to 10s. per barrel of 26"4: gallons, with an expense of 5d. per tree. 

 From amongst several the case of a Virginia orchard is quoted of 

 which one-third was subjected to the arsenical treatment, whilst the 

 other' two-thirds remained untreated. In the treated portion the 

 amount of healthy fruit exceeded by 50 per cent that of the untreated 

 portion, and by 100 per cent as regards market value. The loss 

 suffered under this heading by the two-thirds of the orchard untreated 

 was valued at =£500. These figures so eloquent plead in favour of 

 this simple, economical, and efficient treatment which will meet one 

 day in France with the same success which it already has in America 

 and Norway. 



Use against Injurious Fungi. — Fusicladium dentriticum, Fuckel 

 (apple scab). — By treating apple-trees with emerald green, against 

 injurious insects, apple scab is, likewise, and to a great extent, dimin- 

 ished. Goff obtained 50 per cent of immaculate apples against 30 per 

 cent on untreated tz'ees with four sprayings of 0'06 per cent bouillie 

 of emerald green neutralized by milk of Hme. Galloway states that 

 0"05 per cent bouillie with a little lime is superior to all other 

 products. 



Phytophthora infestans, De By. (potato disease). — Galloway greatly 

 recommends to combat simultaneously both the potato disease and 

 the Colorado beetle a bouillie consisting of 1,00 litres of bouillie borde- 

 laise with 4-10 grammes of emerald green (that is, 4-10 parts of 

 emerald gi-een by weight to 100,000 parts by measure). 



Use against Injurious Insects. — The injurious insects com- 

 bated in America by this process are very numerous, and will now be 

 enumerated, describing only those which ravage European plants and 

 those of America which are of particular interest, because they may 

 eventually prove dangerous to our crops. 



Antlionomus Pomorum (apple weevil). — The cleaning of the trunk of 

 the tree and its branches and coating with lime bouillie bordelaise or 

 with acidified green vitriol are treatments capable of destroying the in- 

 sect in its winter shelter. Spraying with copper arsenite a little before 

 flowering and during the summer may poison and destroy the adult 

 insects which escape the winter treatment. The results of this method 

 are perfect (Debray). Goethe does not share this opinion. 



Anthonomus Grandis, Boh. (cotton weevil). — F. W. Maly advises 

 spraying with copper arsenite bouillie to destroy this weevil, the larvas 

 of which and the perfect insects destroj^ the cotton flowers. 



Zahbrus Gibbus, F. (Zabre bossu). — An arsenical spraying at the 

 right time kills these larvae. 



Crioceris Asparagi (the asparagus beetle). — Vivien recommends for 

 the destruction of the perfect insects and their larvae sprayings with a 

 bouillie prepared thus : Mix a solution of 2 lb. of blue vitriol in 8 

 gallons of water with 0-4 gallon of a concentrated solution of sodium 

 arsenite of 15° B. ; then add the requisite amount of carbonate of 

 soda to alkaline reaction (it takes about ^ lb.) ; then it is again acidulated 



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