FORTY-THIRD ANNUAL REPORT. 113 



GENERAL TREATMENT FOR PLUMS. 



Plum trees may be infested with the San Jose or by the European fruit 

 scale. The treatment for them is the same as recommended for scale 

 (m apples. (Page 108.) 



Just Before the Buds Open, spray with the dilute lime sulphur (or 

 the bordeaux mixture) and arsenate of lead, 21/0 to 3 lbs. to a barrel. 

 This is to prevent leaf-spot, fruit rot, black knot and curculio. 



Arsenate of lead is preferable to paris-green on all stone fruits, owing 

 to tenderness of foliage in such fruits. 



Immediately After the Blossoms Fall, it is very essential to make 

 another spraying using the dilute lime-sulphur or bordeaux mixture or 

 self-hoiled lime-sulphur, and two pounds of arsenate of lead to every 

 50 gallons. (For the Japanese varieties use the self-boiled lime-sulphur 

 or dilute the bordeaux one-half.) This spraying is to prevent the leaf 

 diseases, fruit rot and curculio. Be sure it is made immediately after 

 blossoms fall. Our experiments last year showed that dilute lime- 

 sul})liur was very satisfactory on plums and it is easier to prepare and 

 spray than bordeaux or self-hoiled lime-sulphur. 



Ten Days or Two Weeks Later, it v^ill pay to repeat the previous 

 spraying, especially if the weather is wet or the curculio is serious. 

 This spraying should be repeated every ten days or two weeks until there 

 is danger' of staining the fruit; stopping at least a month before pick- 

 ing time. 



On varieties especially susceptible to rot, an application of weak 

 copper sulphate may be made about two weeks before ripening. One 

 pound of copper sulphate to 150-200 gallons of Avater. No poison need 

 be used. 



Black Knot. Early in the spring a careful inspection should be 

 made of every tree, and all "black knots" cut out and destroyed. Cut 

 back several inches below the knot. Disinfecting cuts as for pear blight 

 is not necessary. Wild cherry trees harbor the disease and if diseased 

 ones are near plum or cherry orchards, they should be destroyed, if 

 possible. 



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