88 A PLANT-DISEASE SURVEY IN TEXAS. 



ROSE. 



Cane canker {C oniothyrium fitckelii Sacc). — On the rose {Rosa 

 spp.) canes or stems brown, sunken patches, 1 to 4 or 5 cm. in length, 

 are formed. The stem may be girdled as the filaments extend 

 through the cortex. Sometimes the open cankers are not so evident, 

 the fungus being more diffuse. The pycnidia are formed just be- 

 neath the epidermis, at length protruding. 



Specimens collected : Austin, 1282 ; San Antonio, 1384. 



Dodder {Cuscuta indecora Choisy). — This was present in a garden 

 where it had grown on several other hosts. 

 Specimen collected : San Antonio, 1374. 



Leaf -blotch {Actinonema rosae (Lib.) Fr.). — This fungus has been 



observed in gardens and nurseries and produces a considerable amount 



of defoliation, especially in the nurseries. 



Specimens collected : Austin, 20, 379, 1278, 1919, 2939 ; Victoria, 2336 ; Stock- 

 dale, 2640; Falfurrias, 2463. 



Leaf -spot {Cercospora rosicola Pass.). — The spots produced by this 



fungus are circular, 1 to 5 mm. in diameter, with a pronounced purple 



border and a brown or grayish center. More or less yellowing of 



the foliage and defoliation occur when the spots are abundant. 



Specimens collected: Austin, 371, 381, 1442; Brenham, 1456; Seguin, 2328; 

 Georgetown. 2373; Victoria, 2524; Gonzales, 2687. 



Powdery mildew {Sphaerotheca humuli (DC.) Burr, and S. pan- 



nosa (Wallr.) Lev.). — The first of these is the greenhouse form and 



is not so common as the latter. Early in the summer roses are very 



commonly completelj^ defoliated by the ravages of jS. pannosa. 



Specimens collected: (1) (/S. humuli) — San Antonio, 1370. (2) (S. pan- 

 nosa)— AvlbWh, 1275, 2940. 



Rust {Phragmidium disciflorum (Tode) James). — The secial stage 

 was so abundantl}^ present that the leaves were very conspicuously 

 chlorotic above, while the orange-colored aeciospores covered the lower 

 surface. 



Specimens collected : Austin, 3119 ; San Antonio, 3181. 



STANDING CYPRESS. 



Powdery mildew {Sphaerotheca humuli (DC.) Burr.) (?). — This 

 mildew was very abundant in one locality where standing cypress 

 {Gilia rubra (L.) Heller) was cultivated in large beds. The lower 

 leaves were attacked first and many were completely killed. No per- 

 fect fruits were found. The mildew showed an abundance of a spe- 

 cies of Cicinnobolus. 



Specimens collected: Austin, 1309, 1437. 

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