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frost. The best appliances for this work are the sheet iron fire 

 pots for burning petroleum, of which there are several kinds, each 

 having its advocates and admirers. 



The pots should be filled "as directed," and placed in the grove 

 when cold spells are to be expected, usually one to a tree, set, 

 however, in the open space between the trees, and an extra row 

 along the east and north sides of the grove, and as a general rule, 

 when the temperature at 2:00 a. m. drops to 26, go through and 

 light them as quickly as possible. This method has saved hun- 

 dreds of thousands of dollars to the orange growers in California. 



Wither Tip 



(Colletotrichum gloeosporioides) 



The effects of this disease, in a general way, consists in a spot- 

 ting of the fruit and leaves and killing back of the twigs, and an 

 attack upon the young newly formed fruit causing it to drop. 

 It has increased considerably in the last 4 or 5 years, and is, no 

 doubt, to some extent blamed for dying tops due to some other 

 trouble. The distinguishing mark of the true wither tip is the 

 appearance of minute black spots on twigs and dead portions of 

 leaves, and a distinct yellow line on these leaves dividing this 

 dead brown leaf surface from that which looks green and healthy. 

 Under a good pocket glass these leaf spots show as small upright 

 fungus growths all over the surface. The disease with this ap- 

 pearance is very common, showing more or less on most dead 

 citrus twigs, and the minute spotting of lemons is often "laid to 

 its charge." 



Many expert pathologists believe that the disease is never serious 

 unless the trees have been weakened by some other cause, and 

 the work of Nematode Worms is mentioned as one of the causes. 

 However, others think it more serious, but spraying with Bor- 

 deaux Mixture, or some form of blue vitriol solution is about the 

 only remedy suggested and of course any treatment tending tc 

 promote vigorous vitality in the tree would be proper. 



Florida Die Back 



This disease begins to show itself in little blisters or swellings 

 on the tender twigs, just a little puff on the twig ^4 to ^ of an 

 inch long and not at all discolored. On cutting open, these blisters 

 will show a pocket of gum, and the twig soon begins to wilt and 

 the leaves drop off. Also often some very large dark green leaves 



