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between the outer bark and cambium layer or inner bark. When 

 this occurs, the cambium is destroyed as far as the congested sap 

 extends, but fortunately the bark bursts under the pressure before 

 the poisous syrupy matter extends very far about the body of the 

 tree. This reduces the pressure until the affected parts dry up, 

 then if the cause is not removed, the same trouble will occur to 

 the heretofore unaffected parts, and eventually girdle and destroy 

 the tree. 



Causes of this form of Gum Disease : Extreme moisture or 

 drouth, clay or hard pan which hold up an excess of water, sand 

 or gravel sub-soil, especially if underlayed with clay or hard pan. 

 All of these conditions will cause this form of gum disease. 



Treatment If possible never allow the soil to get too wet or 

 too dry. If underlayed with clay or hard pan, blast through and 

 loosen it up if it is possible. Where sand and gravel exist I have 

 known good results from digging one or more trenches, 2^ feet 

 deep between the rows, and rilling with manure and trash, to 

 serve as a drain and nourish small roots. In addition to the above, 

 remove the earth from about the trunk so as to leave the top 

 of the large roots exposed, then use a horseshoer's knife with a 

 turn at the end of the blade. With this a groove can be cut through 

 the bark from the roots to the large branches. If a small tree one 

 groove is plenty, if a large tree cut grooves about two inches apart, 

 then paint all of the body with pure neats foot oil. If a very bad 

 case I would recommend cutting back the branches quite severely. 



Trees budded on the seed stalk not less than six inches above 

 the ground are usually less liable to this disease than those budded 

 lower, and the higher the bud the better, as the seedling wood 

 is much less liable to gum disease than the bud, as a rule. Care 

 should be taken, in any case, not to plant the tree too deep. Some 

 advocate planting so shallow that the crown roots are right at 

 the surface. 



Scaly Bark of Citrus Trees 



This disease generally appears first on the large branches near 

 the body of the tree, but in severe cases the whole body is affected. 

 It first appears like small warty eruptions. Small quantities of 

 gum ooze from the warts. This dries up and the eruptions ap- 

 parently heal, but are immediately followed by others which spread 

 quite rapidly, causing the outer bark to crack and scale up, hence 

 the name "Scaly Bark." This disease is considered by many to be 

 contagious. 



