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SUMMARY. 



1. Blight attacks trees only when over 5 years old and 

 which are in bearing. It is first manifested by a sudden wilt- 

 ing of the leaves, which soon becomes so bad as to continue 

 even in wet weather. At the beginning of the rainy season 

 following the wilting, vigorously growing sprouts start from 

 the trunk and larger branches. These often continue gi owing 

 several years, but finally sicken and gradually decline. The 

 spring following the wilting of the top, the branches which 

 have now become nearly leafless, bloom profusely. These 

 flowers continue to appear for two or three weeks after normal 

 blooming is over. They are small, however, and almost never 

 set fruit. Very little fruit is produced by blighted trees. 

 After flowering, the branches usually die, often leaving only the 

 sprouts from the trunk alive and growing. The whole top 

 may be attacked at once or only a single branch, but in any 

 case the entire top ultimately becomes blighted. The affected 

 trees usually linger for many years and rarely die outright, 

 though they may be finally reduced to mere stumps. The 

 roots for the first year at least seem perfectly normal. The 

 annual loss from this disease in Florida is about $150,000. The 

 cause is unknown but it is probably a contagious malady, and 

 so far as known, is incurable. Affected trees should be dug up 

 and burned as soon as they show this disease, and healthy ones 

 set out in their places. 



2. Die-Back or Exanthema is apparently caused by mal- 

 nutrition, accompanied by improper drainage, improper culti- 

 vation, &c. The disease may be recognised by the very large 

 dark pointed leaves, and the reddish brown stains on certain 

 of the new growth twigs, which latter die-back for a consider- 

 able distance. Brown eruptions occur very abundantly on 

 young and old twigs, all of which finally die back. Swellings 

 produced by gum pockets in the wood occur very abundantly 

 on the young twigs. Multiple buds form in the axis of the 

 leaves. Diseased trees bear little fruit, and that formed soon 

 assumes a pale green colour, then a light lemon yellow, be- 

 coming coloured prematurely. The fruits are very commonly 

 more or less disfigured by the characteristic reddish brown 

 stain. A very large percentage split open and drop before 

 ripening. The loss from this malady is about $100,000 

 annually in Florida. Withholding all organic nitrogenous 

 manures, ceasing to cultivate and mulching the soil have been 

 found beneficial treatments. In cases where the disease has 

 been produced by wet soils good drainage will frequently be 

 found an effective remedy. 



3. Scab or Vekrucosis attacks principally sour oranges and 



