90 STATE HORTICULTURAL SOCIETY. 



BORDEAUX MIXTURE. 



Sulphate of copper -4 pounds. 



Lime 5 pounds. 



Water 2'2 gallons. 



EAU CELESTE. 



Sulphate of copper 1 pound. 



Ammonia 1 pint. 



Water 22 gallons- 

 Simple solution of sulphate of copper, one pound to 22 gallons of water. 



MODIFIED EAU CELESTE. 



Sulphate of copper 2 pounds. 



Ammonia 1}4 pints. 



Carbonate of soda i 2 pounds. 



Water 22 gallons. 



SULPHIDE OF POTASSIUM. 



Sulphide of potassium 5 ounces. 



Water 10 gallons. 



" If these solutions cau be used at tlie right time, any of them will do 

 the work, as they will destro}^ every spore or particle of fungus with which 

 they come in contact. 



"The Bordeaux mixture will probably have the most lasting effect, but 

 the lime injures the appearance of the fruit, if it is applied after it has 

 developed. 



" For ordinary work the different forms of eau celeste or the copper 

 carbonate will be found well adapted. 



" For a long time these remedies have been used in France for the 

 destruction of fungi, and through the experiments and reports of our 

 national Department of Agriculture they are coming into general use in 

 this country. 



THE BhACK-KT^OT—PlowHghtia morbosa. 



" The disease that has been most destructive to cultivated plum trees is 

 commonly known as the black-knot. It receives its name from the dark, 

 wart-like swellings that it causes on the trunks and branches of plum and 

 cherry trees. It seems to be particxdarly destructive to our wild choke- 

 cherry, whose trunks and branches are often literally covered with its 

 unsightly knobs. 



" The disease is of American origin, and for a long time has been a 

 serious hindrance to plum culture in many parts of the country. 



"The plum orchards of Europe have as yet escaped its ravages, but 

 it is likely at any time to appear there. It is somewhat particular in 

 its choice of host plants, as it is not found on the wild black cherry, 

 (Prunvs seroUna), while it is of frequent occurrence on wild red, 

 (P. Pennsylvanica) and choke-cherry (P. Virgiiiiana), and on the 

 American (P. Americana) and beach (P. marifima) plums. For a 

 long time the nature of the disease was unknown, but it was generally 



