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5. Foot rot or mal-di-gomma is the most widespread of all orange dis- 

 ease. The total damage which it causes is greater than that resulting 

 from any other one malady, in Florida alone, amount ing to nearly 

 $100,000 annually. It may be recognised by the exudation of gum 

 from definite patches of the tree near the base: A separative layer 

 is formed by the tree delimiting the diseased bark ; the edges of the 

 bark, thus freed, curve up away from the tree, dry out and finally fall off. 

 These patches are enlarged by the disease spreading to the adjoining 

 bark. Other patches also form on fresh bark. The malady spreads 

 down the roots and latterly around the trunk. It extends through the 

 bark and cambium layer into the wood, killing all the tissues as far as 

 it extends. In many cases the tree is finally girdled, which of course 

 results in its death. The accompanying or premonitory symptoms 

 are sparse foliage small yellow leaves, and the dying of small limbs 

 over the tree. The disease is apparently concagious probably being 

 caused by some minute parasitic organism. It is also thought that 

 improper aeration of the roots induces the disease. Sweet seedling 

 -orange trees and lemons are particularly subject to the malady, while 

 grape fruit is but slightly subject to it, and sour orange is almost 

 wholly exempt. The malady may be prevented by using sour 

 oraoge stocks on lowland, and flat woods, and grape fruit stocks on 

 high and dry pine lands. Removing the soil from around the crown 

 roots is the most effective treatment. This can be best done by using 

 a stream of water uuder considerable pressure. This washes the soil 

 away without injuring the roots, cutting away the diseased portions 

 of bark and wood and washing or painting the wounds with a solution of 

 sulphurous acid, carbolic acid, or sulphur wash is recommended as bene- 

 ficial. Avoid the excessive use of nitrogenous organic manures, ex- 

 cessive cultivation, and immoderate irrigation. Grive good drainage in 

 all cases and if the trees are planted too thick, so that the ground is 

 shaded, thin them out. 



6. Melan§se, which attacks all citrus fruits is a new disease. It 

 is as yet known only from a few points in Florida and does not cause 

 much damage, probably only about 5;5,000 in 1894. However, it 

 seems to be spreading, and is capable of causing great losses should it 

 become widely distributed. It forms minute brown spots on the leaver, 

 twigs, and fruits. These brown spots appear when the fruit and leaves 

 are still young, and do not form on old tissue. They reach a size of from 

 T5Tr iJioh in diameter and are often very numerous some- 

 times running together over large areas, greatly staining and disfigur- 

 ing the fruit. In bad cases the trees are much injured by the malady, 

 but ordinarily most of the damage results from the discolouring of the 

 fruit. Lemons particularly are unsaleable if attacked by melanose to 

 any considerable extent. The cause of this disease is not certainly 

 known but it is very probable some minute vetjetable parasite.- 

 JBordeaux mixture or ammoniacal solution of copper carbonate are 

 very effective remedies if applied two or three times to the young fruits. 



