DISEASES OF TREES AND SHRUBS. 79 



leaf -blight {Phleospora Tnultimacidans Heald and Wolf, 32). — 

 Definite, irreo;nlar, circular or angular spots, dark brown or purple, 

 and 1 to 3 mm. in diameter, are produced upon the upper surface 

 of the leaves. They frequently show a brown center, and on the 

 under surface the spot is brown throughout with a darker brown 

 border. The spots frequently become confluent and produce dirty- 

 brown, extended, dead areas. The spots may be very numerous, and 

 in nurseries much defoliation results. (PI. XIV, fig. 2.) 



The pycnidia are hypopliyllous; spores nearly cylindrical, straight 

 or curved, hyaline, 30 to 50 by 3.5 to 5 /x, and two to three septate, 

 sometimes four septate (PI. V, fig. 7). (See also Walnut.) 



Specimens collected: Austin, 1398, 1535; Brenham, 1462; New Braunfels, 

 1682 (type specimen) ; Llano, 1767; Victoria, 2503; Gonzales, 26.55; Floresville, 



2858. 



SYMPHORICARPOS. 



Powdery mildew {Microsphaera diffusa Cke. and Pk.). — Both the 

 conidial and perithecial condition were abundantly present on Si/m- 

 phoricarpos orhiculatus Moench where this was observed. Causes 

 little apparent injury. 



Specimen collected: Austin, 1311. 



TREE-OF-HEAVEN. 



Shot-hole {Cei'cospora glandiilosa Ell. and Kellerm.). — This disease 

 on the tree-of -heaven {Ailanthus glandulosa Desf.) forms circular 

 spots 1 to 3 mm. in diameter, brown, becoming gray above, with an 

 elevated margin. The whitish conidial tufts are very conspicuous on 

 the lower surface. The entire diseased area at length drops out, 

 producing on the leaves a " shot-hole " effect. 



Specimens collected : New Braunfels, 1698 ; Austin, 2862. 



TRUMPET CREEPER. 



Leaf -mold {Cercospora sordid a Sacc). — On the lower surface of 

 the leaf of trumpet creeper {Tecoma radicans (L.) Juss.) a diffuse, 

 indefinite, brown or olivaceous coating is formed. This shows on 

 the upper surface as a slight chlorosis of the tissue. 



Specimens collected: Bastrop, 2028; Victoria, 2519. 



Leaf-spot {Septoria tecoTMB Ell. and Ev.). — The diseased areas are 

 purplish throughout in the earlier stages of their development, 2 to 

 3 mm. in diameter, and Avith an indefinite outline. Later a minute, 

 central, grayish patch is formed in which the pycnidia are produced. 



Specimen collected : Austin, 1317. 



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