72 



Treatment If a very bad case, I would advise the removal of 

 the limb or branch, but ordinarily this disease can be cured by 

 scraping off all of the rough, scabby bark, then treating with a 

 strong solution of caustic potash, one pound dissolved in six gal- 

 lons of water. Spray or brush the affected parts thoroughly with 

 this solution three or four times during the year. I have also 

 seen good results from the use of coal tar and carbolic solutions 

 used in place of the caustic potash. 



Chlorosis 



(Lack of Nutrition) 



In this trouble the leaves become yellow and pale, and the 

 mottled appearance of the leaves often goes with it, though the 

 latter trouble alone seems more easily remedied than the first, and 

 when affecting young leaves and grafts will usually disappear in 

 a short time if proper care is given the tree. 



The sub-soil when very light or covered by a hard pan seems 

 often to cause Chlorosis, and sometimes the Nematode Worm 

 (similar to the potato eel worm) is blamed as the cause. Each 

 case should be carefully investigated, the cause found and cor- 

 rected. It is simply lack of proper nourishment in the tree. 



Damping Off of Citrus Seedlings 



(Rhizoctonia fusarium) 



This is the shrinkage and decay of the stalk of citrus seed-bed 

 stock and causes much loss every year. It is caused by an over wet 

 soil. Seed beds should have one inch of clean sand on top with 

 heavier soil beneath, and then only sufficient water used to give 

 the plants good growth. Beginners should dig into the soil fre- 

 quently to ascertain its moisture, and not water whenever the top 

 sand gets dry. 



If the "damping off" begins, stop watering at once and allow 

 the bed to get as dry as the plants will stand. Then with a long 

 toothed rake loosen the surface thoroughly, raking and cross- 

 raking, even if some plants are disturbed and killed. This breaks 

 up and destroys the fungus growths in the soil and will save many 

 of the plants not yet attacked, 



Frost Protection 



With the citrus grower this is a very live and important sub- 

 ject, as very few places in Southern California escape an occasional 



