46 CALIFORNIA CITRUS CULTURE. 



which is serious. Removing the earth from the main roots, cutting out 

 the diseased portion and disinfecting will usually effect a cure. Mr. 

 R. P. Cundiff, of Riverside, California, claims to have used large 

 quantities of gypsum, 50 per cent pure, working it into the earth about 

 the trees with apparently excellent results. 



Splitting. 



Here again the name tells the story. Oranges alone are attacked 

 the oranges split. It is probably caused by spasms of growth caused 

 by irregularities in culture, irrigation or seasons. Navels, especially, 

 suffer. As we should expect, it is much more common some years than 

 others. We can do something, I think, by regularity and punctuality 

 in our care. Of course we can not control the seasons. 



Puffing. 



This is described by the name. The rind of the orange bulges out in 

 sections, is often very rough, and is easily injured in handling. I have 

 seen it very pronounced in case of trees pushed to extremes, by excessive 

 fertilization. The orange loses its flavor and is likely to become worth- 

 less. Soil and season seem to influence in this affection, and, as we 

 should expect, it is more serious some years than others. Improper 

 irrigation may be provocative of this disease. 



Peteca. 



In this disease, which is usually seen only in the packing-house on 

 lemons, there is a pitting of the surface of the fruit. It is injurious 

 only in marring the appearance of the lemon. The cause is obscure. 



Brown Spot. 



This is a serious affection, more frequent in the navel orange, which 

 marks the rind of the finest fruit, and appears only after the fruit is 

 picked for some days. Often there is no discoloration until the fruit 

 is shipped. It is early picked fruit that shows the spot. The cause of 

 this spotting is not certainly discovered. It would seem that some 

 injury to the epidermis of the fruit may be the seat of the trouble. 

 Brown spot is much less common near the coast. I first had samples 

 from San Fernando, then San Dimas, then Redlands, where that first 

 season it injured fifty per cent of the early picked fruit. 



Fungi, Molds, Etc. 



Our citrus trees often suffer severely from the attacks of fungi. 

 These very simple organisms are among the lowest of plants. They 

 develop no chlorophyll, do not take oxygen, but depend upon other 



