DISEASES OF PLANTS. 1055 



An anthracnose and a stem rot of the cultivated snapdragon, 



F. C. Stewart [iVe^r York State Sta. Bui. 179, _pp. 105-111, ph. J).~ 

 In 1897 the author's attention was called to an anthracnose of snap- 

 dragons occurring in a greenhouse on Long Island, and upon inquiry 

 he learned that it was a rather connnon disease, being the most 

 destructive of the diseases to which this plant is subject. It attacks 

 the plants at any stage of their growth, in the greenhouse and in the 

 field. In the greenhouse it is most destructive in the fall and spring, 

 wliih^ in the fields its ravages are most conspicuous during August and 

 Septem])er. 



It attacks the stems and leaves of the plants. Upon tlie stem it 

 produces elliptical sunken spots 3 to 1() mm. in length. Upon the 

 leaves the spots arc circular, and have a diameter of from 3 to 5 mm. 



The cause oi this disease is said to be Oolletotrlchum (intirrh'ivl, n. 

 sp. , which is described. An experiment was undertaken for the pre- 

 vention of the disease, in which plants were sprayed once a week with 

 Bordeaux mixture, receiving during the course of the summer 17 appli- 

 cations. In August the contrast between the sprayed and luisprayed 

 plants was very striking, and in September the unsprayed plants were 

 completely ruined while the sprayed ones were in perfect health. As 

 recommendations for treatment the author suggests that cuttings should 

 be made from healthy plants only, and where the disease is troublesome 

 spraying with Bordeaux mixture, l)eginning as soon as the cuttings are 

 rooted and continuing until the plants are transplanted in the fall. So 

 far as known at present, this anthracnose attacks no other plant, and 

 growers whose grounds are free from the disease will have no trouble 

 so long as they propagate from their own stock or seed. 



The stem rot described was first observed in December, 1898. It 

 attacks chiefly the succulent shoots, causing several inches of the ter- 

 minal portion to Avilt and die. In some cases, especially where the 

 shoots have become somewhat woody, a section of the stem turns 

 brown while the portion beyond remains green. In a short time the 

 whole l)ranch dies. 



This disease is attributed to the attack of a species of Phoma. 

 Inoculation experiments showed that the disease was readily commu- 

 nicated, shoots which were inocidated generally dying in from 4 to 10 

 days. The species of the fungus has not yet ])een determined, and 

 from the nature of the attack it is thought that the disease could prob- 

 ably be controlled l)y spraying with Bordeaux mixture, as suggested 

 for the anthracnose. 



Report of the department of botany, A. A. Tyler {Arizona Sta. lipl. 1900, 

 j)p. 167-170). — A brief account is given of the investigations which have been con- 

 ducted at the station on the crown gall, the detailed report on which is given in Bul- 

 letin 33 (E. S. R., 12, p. 458). Experiments have been continued on alfalfa root 

 rot, in which plats have been laid off, divided into equal portions, and treated with 



