110 FLORIDA FRUITS ORANGES. 



CHAPTER XII. 



THE RUST MITE.* 



Discoloration of the Fruit. The brownish discoloration 

 of the rind of oranges, familiarly known as "rust," has, 

 since the production of this fruit became an important in- 

 dustry in Florida, given great concern to the producers, 

 and occasions annually serious loss by affecting injuriously 

 the salableness of the fruit. In appearance the rust varies 

 from a light- or dark-brown stain beneath the cuticle to a 

 rough incrustation resembling an exudation of resinous 

 gum upon the surface. In the former case the golden 

 color of the ripe orange is more or less obscured, and in 

 the latter entirely destroyed by the discoloration. When 

 entirely coated with rust the surface becomes finely chapped 

 and roughened, giving to the unripe fruit a likeness to rus- 

 set apples. 



The season during which rust makes its appearance in- 

 cludes nearly the entire period of growth of the fruit, be- 

 ginning in early summer, when the fruit has attained less 

 than one third its full size, and continuing late into autumn. 

 Its most rapid increase is, however, in August and Sep- 

 tember, as the orange approaches maturity. Karely is 

 there any real increase after the rind begins to ripen, al- 

 though the discoloration usually attracts attention just at 

 this time, and frequently occasions unnecessary alarm. 

 On the contrary, there is always a perceptible brightening 

 as the fruit attains its full color, and oranges slightly af- 

 fected, or affected early in the season, when fully ripe show 

 but little trace of rust. 



"Report of H. G. Hubbard, Special Agent, to the United States Ento- 

 mologist. 



