THE AORICULT 



URAL JOURNAL. 



different forms. The young aphides are 

 a light brown and somewhat transluent, 

 whilst the adults are an intense and 

 shining black. Among these latter num- 

 bers of winged insects will also be noticed, 

 and also others with the wings just form- 

 ing and still in the form of pads, pressed 

 closely to either side of the thorax. This 

 form is spoken of as the pupa or nymph, 

 and from it develop the winged indi- 

 viduals. Its appearance among a colony 

 appears to be due to the growing shortage 

 of supplies, and the cjnse^|i,ient necessity 

 for a search for more food. The flying 

 aphides have four wings, by the aid of 

 which they can travel with the wind for 

 good distances. The winged insects 

 possess the same procreative functions as 

 the wingless, and whilst they are never 

 so numerous, still they help to spread in- 

 festation to a very great extent. 



In Maritzburg the pest may usually be 

 found upon peach trees, which have be- 

 come infected, all the year round. During 

 the winter months it confines itself more 

 to the under - surfaces of low - lying 

 branches, and also shelters around the 

 trunk just beneath the surface of the soil. 

 In the shelter of my own garden I also 

 noticed it apon suckers which remained 

 in leaf throughout the winter, and very 

 early seedlings which sprouted there all 

 had a colony upon the crown of the root 

 early in September. Reproduction is very 

 slight in the depth of winter, but directly 

 the buds begin to swell the aphides repro- 

 duce rapidly, and, in the instance under 

 my observation, this spring the tree was 

 well infested before the flowers were out 

 in August, and during September multi- 

 plied very rapidly and did considerable 

 injury, despite the early advent of the 

 rainy season. The effect of the attack is 

 to dwarf the growth, so that shoots which 

 should be five or six inches long remain 

 stunted in the form of rosettes of dis- 

 torted leaves. After a good spell of rain 

 the tree recovers and makes some head- 

 way, but never makes the growth that it 

 should. 



Treatment. 

 The black peach aphis succumbs readily 

 to contact insecticides, and for this pur- 

 pose either paraiHn emulsion or a 

 decoction of tobacco and soap may be used 

 with advantage. To be at all thorough the 



treatment must, of course, be an early 

 one, and it is best to start by destroying 

 those sheltering on the crown and lower 

 p irts of the tree during the cold weather. 

 For this purpose my friend, Ohas. French, 

 the Government Entomologist of Victoria, 

 who has given this pest more attention 

 than I have been able to, recommends, 

 after the removal of some of the surface 

 soil (without uncovei'ing the roots), the 

 application of a couple of gallons to each 

 tree of a solution of blue-stone, using one 

 ounce to two gallons of soft water. 



In spraying trees for this pest either 

 the diluted paraffin emulsion or the 

 tobacco and soap solution, the formulas 

 for making which are appended, may be 

 used, but the degree of success will de- 

 pend to a very great extent upon the 

 thoroughness of the application and the 

 quality of the pump used. As regards 

 pumps, one is limited to the local supply, 

 and so I can only recommend the Deming 

 " Success " or " Galloway Knapsack," or 

 the Nixon pump fitted to a barrel. To all 

 these pumps Deming's fine Vermorel 

 cyclone nozzle should be attached for 

 this work in preference to the " Bor- 

 deaux " nozzles, or any of those supplied 

 with Nixon's pump. 



Deming's pumps are stocked bv Messrs. 

 Wilkinson & Co. and Steel, Murray & Co., 

 Pietermaritzburg, and by Messrs. P. Hen- 

 wood, feoutter & Co., Durban ; the latter 

 firm also stock Nixon's pumps. 



Paraffin Emulsion. 



Soap 1^ pounds. 



Paraffin 5 gallons. 



Water 2^ gallons. 



Take whale-oil or common bar soap; 

 cut up and boil until dissolved in water. 

 While boiling add solution to the paraffin. 

 Churn violently ; five minutes if with 

 pump or syringe, or fifteen if with paddle. 

 Dilute, using nine parts of Water to one 

 of emulsion. 



Tobacco and Soap Solution. 



Tobacco (strong) ... 2 ounces. 



Soap (common) ... 5 ounces. 



Water 1 gallon. 



Boil the tobacco thoroughly and strain ; 

 dissolve soap in hot tobacco solution and 

 make up to one gallon. 



