80 A PLANT-DISEASE SURVEY IN TEXAS. 



TULIP TREE. 



Leaf -blight (Gloeosponum liriodendri Ell. and Ev.). — The leaves 

 of the tulip tree (Liriodendron tulipifera L.) may show extended, 

 dead, brown patches which involve part or the whole of the leaf lobes, 

 advancing from the tips or margins. The spots are light brown and 

 darker at the advancing edges. Gloeosporium liriodendri is present, 

 but it is impossible to say whether it is the entire cause of the blight. 



Specimens collected: Xew Braunfels, 1680; Seguin, 2281. 



Leaf-spot. — The leaves of the tulip tree in one locality showed a 

 definite spotting which indicates a fungous trouble, although no fun- 

 gus spores were found. The spots are irregularly circular, i to 8 

 mm. in diameter, dark brown or black, surrounded by a broad zone of 

 yellow which fades out without a definite boundary. On the lower 

 surface the spots are less pronounced and more of a purplish-black 

 color. The affected leaves may show only a few spots or as many as 

 25, and in some cases extensive, dead, brown areas may be produced. 



Specimen collected : Georgetown, 2370. 



UMBRELLA CHIXA TREE. 



Root-rot (Ozonium onmivorum Shear.). — This was found on an 

 umbrella China tree (Jlelia azedarach L.) in a nursery where the 

 root-rot had killed the young trees of black locust in an adjacent plat. 



Specimen collected: Georgetown, 2352. 



VIRGINIA CREEPER. 



Leaf-spot (Cercospora pustula Cke.). — This fungus produces on the 

 Virginia creeper (P seder a quinque folia (L.) Greene) dark-brown, 

 jDurple. or almost black spots, subcircular or angular, 1 to 2 mm. in 

 diameter or smaller, and generally surrounded by a zone of yellow. 

 Colors are more dilute on the under surface. 



The conidiophores are epiphyllous, fasciculate in rather sparse 

 groups, continuous, 35 to 45 by 4 /x. uniformly yellowish brown; 

 spores smoky, clavate, straight or curved, 28 to 72 by 4 /*, and two 

 or three septate. (PI. Ill, fig. 5.) Differs from C. ampelopsidis in 

 having smaller spores, and epiphyllous conidiophores. 



Specimens collected : Austin, 1277 ; Xew Braunfels, 1669. 



Leaf -spot (Phyllosticta ampelopsidis Ell. and Martin). — Definite, 

 circular, brown spots, 1 to 5 mm. in diameter, with a darker border, 

 are characteristic of this trouble. 



Specimens collected: Austin, 1547; New Braunfels, 1670. 

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