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more, but sooner or later they show small and usually yellowish 

 leaves, and begin to decline. Often too, such shoots wilt and 

 shew all the symptons of a fresh case of blight. Ordinarily 

 the tree continues to decline gradually and is finally removed 

 before it dies, to make place for a new tree. Again, cases may 

 linger ten years or more, making a slow sickly growth, and 

 even bearing a little fruit. Cases of real recovery from genuine 

 blight are, however, almost entirely unknown, although 

 hundreds of growers have been deceived by the vigorous growth 

 of water sprouts sent out by blighted trees after the first 

 wilting. 



A most remarkable fact is that the roots of blighted trees 

 invariably seem to be entirely healthy. The vigorous growth 

 of water sprouts they support shows that they are capable of 

 considerable functional activity. 



No anatomical features which are characteristic of blight 

 have yet been found. Under the highest powers of the micro- 

 scope the tissue of every organ of blighted trees appears to be 

 normal, which is in striking contrast to foot-rot and die-back. 

 The physiological activity of the leaves and branches, however, 

 is very much deranged, as has been proved by experiments on 

 the loss of water from blighted twigs. 



Varieties of Trees Attacked. — Almost all citrus fruits are 

 attacked by blight, although some sorts are nearly exempt. 

 Common oranges (Citrus Aurantium), tangerines and man- 

 darins (Citrus nobilis) and grape fruit (Citrus decumana), in 

 about the order named, are the most susceptible. Lemons 

 blight less than any of the fruits mentioned, while limes and 

 sour oranges, especially the latter, are almost exempt from this 

 disease. Certainly not more than one sour orange tree in a 

 thousand is blighted even in regions most liable to the malady. 

 Curiously enough the sort of stock used appears to have no 

 influence in increasing or diminishing the susceptibility of trees 

 to the disease. Common oranges budded on sour orange roots 

 are apparently as liable to blight as are sweet seedling trees. 



Situations most Liable to the Disease. — Although blight 

 attacks citrus fruits growing on all kinds of soil, it is most 

 common on trees growing on very light, sandy hammock (1). 

 Such soils are usually composed almost wholly of sand with an 

 admixture of decaying vegetable matter ; sometimes, however, 

 they are underlaid at a depth of from 4 to 12 feet with clay or 

 hardpan (sandstone) . Trees growing on clayey hammock or 



(1) Hammock land is that which was originally covered with hard 

 woods, especially live oak, magnolia, hickory, &c. 



