DISEASES OF CULTIVATED PLANTS 509 



The Fig Rust. This is another trouble that is well known to 

 all who have raised figs or seen them growing. This is the disease 

 that usually causes a defoliation of the fig trees in the late summer 

 or early fall. The leaves affected first show a number of small, 

 raised, light salmon-colored pustules on the under surface. These 

 increase in number until the leaf surface is practically covered. As 

 the number of pustules become very large, the leaf begins to die, 

 usually beginning near the margin. Later the leaf falls to the 

 ground. 



This disease is everywhere in Louisiana where the fig grows, 

 and in probably every locality it causes a defoliation of the trees. 

 Fortunately, however, the leaves do not usually become severely 

 affected until the latter part of August or September, and the def olia* 

 tion at this time does not seem to materially injure the crop. Occa- 

 sionally the infection will come early enough to cause a shedding 

 of some of the late figs, but this is rather unusual. 



Just what effect the rust has on the vitality of the trees is hard 

 to answer. The trees nearly always put out a fresh crop of leaves 

 in the fall, but these are killed by the frost before they are of much 

 service. This early defoliation, year after year, would mean the 

 death of some kinds of trees, but the fig does not seem to be much 

 injured. The young leaves and shoots come out in the following 

 spring with as much vigor as ever. 



This disease has long been known to be due to a fungus known 

 as Uredo fid, or Physopella fid. How the fungus lives from year 

 to year has not been thoroughly settled. The uredospores may live 

 over the winter on old leaves on the ground, but if this is the case, it- 

 seems strange that the infection does not begin earlier in the season. 

 There is no treatment for this disease that can be recommended. 

 (La. E. S. B. 132.) 



Soft Rot of the Fig. This is a trouble which is well known to 

 every one who has ever raised figs. The trouble occurs chiefly dur- 

 ing rainy spells in the summer when the fruit is ripening. The 

 fruit sours, becomes soft and rotten, and, finally, generally falls to 

 the ground. At the time the fruit falls, it is generally so soft that 

 it all goes to pieces when it strikes the ground. 



The rot itself is generally due to specific fungus, though there 

 are a number of factors which govern the severity of the attack. 

 The fungus is a very common black mold which grows on almost 

 everything in almost every place, and known technically as Rhizo- 

 pus nigricans. This is the same fungus which causes the foul smell- 

 ing, soft rot in sweet potatoes, and it is also the same one which 

 frequently grows on bread that has been kept too moist. In fact, it 

 is so common on bread that it is often called Bread Mold. 



There is very little that can be done to control this trouble, 

 especially in those regions where the rainfall is large. But perhaps 

 the loss can be decreased to some extent by following the suggestions 

 given below: 



1. Pick the figs very often, and do not allow any to hang on 

 the trees after they are ready to pick. 



