30 A PLANT-DISEASE SURVEY IN TEXAS. 



Fire-blight (Bacillus amylovorus (Burr.) Trev.). — This trouble is 

 rather common in our territory and is responsible for a very con- 

 siderable amount of damage to the pear trees, blackening the leaves 

 and twigs. 



Specimens collected : Austin, 1319 ; Brenham, 1460 ; Boerne, 1657 ; Elgin, 

 2001; Locknart, 2081; San Marcos, 2123; Nursery, 2571; Cuero, 2600; Stock- 

 dale, 2628 ; Flatonia, 2713 ; Hallettsville, 2785. 



Leaf -blight (Cercospora minima Tracy and Earle.) — This fungus 

 produces irregular angular areas 1 to 10 mm. or more in diameter, 

 brown or sometimes showing a grayish color in older portions, and 

 frequently bounded by the principal veins. Spots may be few in 

 number, or they may be sufficiently abundant to coalesce and nearly 

 cover the leaf. Affected leaves frequently show a considerable 

 amount of chlorosis, and man}^ fall from the tree. In several locali- 

 ties the pear trees were nearly defoliated by this disease. 



Specimens collected: Victoria, 2511; Nursery 2541; Cuero, 2605; Gonzales, 

 2707 ; Flatonia, 2712 ; Hallettsville, 2775 ; Falfurrias, 2454. 



Leaf -spot (Fabraea maculata (Lev.) Atk.). ! — These spots are gray- 

 ish brown, circular, and about 2 to 4 mm. in diameter. The black 

 pycnidia are sparsely present on the upper surface. 



Specimens collected: Austin, 364; New Braunfels, 1705; Llano, 1761; Stock- 

 dale, 2630. 



Eust-spot (Gymnosporangium sp?). — These are the Phyllosticta- 

 like infections of a rust. Small circular spots about 2 or 3 mm. in 

 diameter are formed. They are brown with a very dark border and 

 a central dark cluster of spermagonia. 



Specimen collected: New Braunfels. 1689. 



PERSIMMON. 



Black leaf -spot (Cercospora fuliginosa Ell. and Kellerm.). — Affected 

 leaves of the persimmon (Diospyros sp.) show circular or subcircular 

 spots, 1 to 5 mm. in diameter, on the upper surface black with yellow 

 border; on the under surface purplish black with indefinite border. 

 With maturity of spots the centers on both surfaces may become 

 brown or gray. In some cases the leaves turn yellow and fall, while 

 in others extended brown, dead areas may be produced before the 

 leaf is cast. 



Our specimens differ from the original description only in the size 

 of the spots (1 to 2 mm.). 



Specimens collected : On Diospyros kaki L. — New Braunfels, 1706 ; George- 

 town, 2361; Victoria, 2537; Stockdale, 2642. All specimens except 2361 are 

 immature infections. 



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