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EXTRACTS FROM CORRESPONDENCES 



REMEDIES FOR APPLE SCAB. 



I am preparing to spray 1,400 ten-year old apple trees with Paris green and want 

 to add something for the scab. Has sulphate of copper been used for the latter dis- 

 ease? — (Charles Patterson, Kerksville, Adair County, Mo.) 



Answer. I would suggest the use of liver of sulphur or sulphide of po- 

 tassium, using the solution of the strength of one-half ounce to the gallon 

 of water. This should be used as soon as prepared, or in other words, it 

 should not be prepared until you are all ready to make the applications. 



In regard to the use of sulphate of copper, the strength of the solu- 

 tion which may be used has not been determined. The following prep- 

 aration may be tried experimentally : In 2 gallons of hot water dis- 

 solve 2 pounds of sulphate of copper (pure) ; in another vessel dissolve 

 2J pounds of ordinary carbonate of soda; mix the two solutions and 

 when all reaction has ceased add 1 pint of liquid ammonia ; then dilute 

 to 25 or 30 gallons. This is easily applied with a good spraying pump, 

 and adheres strongly to the parts sprayed. Its preventive action 

 lasts for a long time. The action of the liver of sulphur is soon dissi- 

 pated. 



APPLE RUST. 



I inclose some apple leaves, affected, as I suppose, by a fungus. Please let me know 

 what it is and how to prevent it. Ouly certain varieties are affected, but among those 

 are some of the best for this climate. — ( James S. Whitmau, Dardanville, Ark.) 



Answer. The leaves are affected with the apple-leaf rust— a species of 

 Roestelia — which is quite common throughout the Middle and Western 

 States, affecting more or less seriously certain varieties over others. 

 The fungus lives within the tissues of the leaves and fruit (when this is 

 attacked), and becomes visible on the surface when ready to produce 

 its spores or reproductive bodies. It is important to state that this fun- 

 gus as it appears on the apple is but one stage in its life history, an- 

 other form appearing earlier in the season on Cedar trees, causing the 

 growth of what is familiarly termed •' cedar apples." This stage on the 

 Cedar is regarded as the first and essential condition of that appearing 

 later on the apple, and it is also the stage by which the fungus hiber- 

 nates, if we may so apply this term. 



Perhaps by making applications of the salts of copper or other fun- 

 gicidal preparations to the apple trees before the spores from the " cedar 

 apples" come upon them the development of the Eoestelia form maybe 

 pre vented ; but so far as we are aware, no experiments have been made 

 to determine this question. The destruction of the cedars, together 

 with the application of preventive remedies is the only course of treat- 

 ment which a knowledge of the facts in the case suggest. 



'The correspondence of the section consumes a large part of the time of the office 

 force, but it is believed thai us an important means of disseminating useful informa- 

 tion it should receive all the attention possible.— B. T. Galloway. 



