15 



time; and when the leaves are dry, the time that Bordeaux would 

 be most effective by adhering best, the disease is at a standstill, as 

 any of the heads which happen to fall on such leaves do not germi- 

 nate even if the}^ adhere. The violent downpours soon wash the 

 fungicide from the smooth upper surfaces of the leaves, where it 

 must adhere to be of any effe'Ct. Moreover, the hillsides are so steep 

 in many places that only knapsack sprayers could be used, and these 

 only with difficulty. In case spraying is resorted to, it will be of 

 most value when applied to the healthy trees near the diseased 

 ones or to those less severely attacked, for the reason that the spray 

 will prevent the infection of the leaves to which it adheres, though 

 having no effect in preventing the formation of new propagative 

 bodies on the already existing spots. 



The disease does not spread with great rapidity. In one case 

 observed it progressed about 200 yards in one year. Many plantings, 

 probably newer ones, iire free from this pest, although climatic con- 

 ditions are such that it could do much damage if once it obtained 

 foothold. After it appears in such places it is merely a matter of 

 time until the entire field is affected, and it is under these condi- 

 tions, when only a small area is affected, that it can be combated to 

 most advantage. Unless prevented, it will extend down the mountain 

 slopes until it reaches drier conditions, the only obstacles to its prog- 

 ress in other directions being strips of forest or grass land or an 

 especially exposed or unshaded slope. The coffee of the " altura " 

 requires less shade than that of the lower lands, but even there it is 

 seldom that there is an excess of shade. If such exists, it could be 

 lessened to advantage, for anj^thing making for drier conditions is 

 unfavorable to this fungus. To cut the shade away entirely, how- 

 ever, would be a remedy worse than the disease, and one which no 

 experienced grower would try. 



ROOT DISEASES. 



In many plantations there are to be found places where all the 

 coffee trees have died out, the largest of such treeless areas covering 

 an acre or more. These areas are usually well marked, being sur- 

 rounded by healthy trees. The death of the trees is due to the action 

 of certain soil fungi which attack the roots, usually the upper ones, 

 and the base of the trunk. The first indication that a tree has been 

 attacked is the drooping and yellowing of the leaves, which later fall, 

 beginning with those of the lower branches. The roots of the trees 

 will be found to be well covered by the thread-like growth of the fungi 

 and partly decayed. There are two types of the disease, which may 

 be classified for convenience according to the color of the accompany- 

 ing fungi as the black {Rosellinia sp.)' and white root diseases. The 



1 Apparently RoseUdnia hunodes. 



