50 



Contact with metals. It is possible that any of these aplications 

 will prove of benefit even if the diseased spots are not cut out. 

 In this latter case, however, care should be taken to saturate 

 the bark of all diseased spots with the solution. 



3. When the diseased trees are old and closely set, so that the 

 ground is much shaded, every other tree should be removed and 

 replanted in a new grove. 



4. Avoid highly nitrogenous organic fertilisers in diseased 

 groves, using preferably nitrate of soda or sulphate of ammonia 

 as a source of nitrogen. 



5. All tools used in infected groves should be cleaned and 

 washed with crude carbolic acid before they are used in healthy 

 groves. 



6. In setting new groves dead trees should be replaced with 

 trees budded on sour orange stock. (Sour stock does better 

 than sweet on low wet hammock lands, and as well on flatwood 

 land. For high, dry lands grape fruit stock may be used, since 

 sour stock does not do well and grape fruit is almost exempt 

 from foot-rot.) 



7. Avoid excessive and deep cultivation in diseased groves. 

 Injuries to the roots, such as are often caused by deep plough- 

 ing, seem to greatly favour the spread of the disease. 



MELANOSE. 



Melanose (from the Greek, black and disease), which in 

 some groves is causing considerable damage, was first brought 

 to the attention of the writers in November, 1892, by Mr. J A. 

 Barnes, who sent specimens to us from Citra. It apparently 

 attacks all citrus fruits, but developes somewhat more freely 

 on the grape fruit than on the other varieties. It is known to 

 affect the grape fruit, common sweet orange, sour orange, 

 lemon, mandarin, and Satsuma. The disease develops most 

 freely on young rapidly growing vigorous shoots. It resembles 

 to some extent the injury produced by the rust mite, and was 

 for a time confounded with this disease. Its refusal to yield to 

 the treatment for rust mite, however, led to the discovery that 

 it is distinct from rust (a brown discolouration of the fruit, 

 caused by the attack of a surface feeding mite, Phytoptus). 



The disease is undoubtedly of very recent origin or intro- 

 duction. It has spread rapidly in the region about Citra, and 

 many of the groves there are badly affected. The malady has 

 also been found to occur to some extent at Ocala, Stanton, and 

 Sand'ord, and is appaiently spreading rapidly. 



The foliage of trees attacked by this disease is greatly in- 

 jured, and consequently the general vigour and productiveness 





