DANGEROUS INTERNATIONAL FOREST TREE DISEASES 57 



to the disease, the attack occurring mainly on branches which are killed 

 by girdling. 



Control of the disease may be possible by eradication of the annual 

 weed swertia from the affected chir pine forests and up to a distance 

 of 200 yards from them. Removal of diseased chir and raising broad- 

 leaf species with chir to serve as windbreaks to prevent the ingress of 

 sporidia into pine forests is suggested for control. Since a plantation 

 crop, at young age, is particularly susceptible. "Selection System" is 

 advisable. 



An indigenous species to India only, chir is raised in south and 

 east Africa. Importation of living plant material except seeds should 

 be forbidden except for experimental purposes following rigorous 

 inspection and retention in quarantine until all latent infections have 

 had time to appear. 



Hosts: Pinaceae — Firms roxburghu Sarg. 



Literature: Bagchee, K. Investigations on the infestations of 



Peridermium Mmalayense Bagchee on Pinus longifolia. II. 



CronArfbrm- himaZayense n. sp. on Swertia spp.' Indian Forest 



Rec. (Bot. Ser.) 18:66. 1933. 



Spruce Rust 



Chrysomyxa deformans (Diet.) Jaczew. A microcyclic rust on 

 Picea mdtMana (Wall.) Boiss. Only the current year's shoots are 

 attacked and become deformed. All needles in the shoot are infected, 

 become stunted, small, thick, twisted with apices curved. When young. 

 emits a disagreeable odor. The short affected orange-yellow tassels 

 stand out prominently. Orange-red telia occupy two continuous flat- 

 tened beds on the upper surface and two rows of smaller ones below. 

 Teliospores are yellow, smooth, round, 9.5 to 12/x broad. 



Attacks mature trees and is widespread. 



This Himalayan spruce is now raised in Europe and America. 

 Care should be taken to see that the rust does not appear in these new 

 homes. 



Hosts: Pinaceae — Picea smithiana (Wall.) Boiss. 

 Literature: Butler, E. J. Some Indian forest fungi. III. Indian 

 Forester 31:611-617. 1905. 



Teak Leaf Rust 



Ottvcxi tectonae (Racib.) Thirum. A microcyclic rust on teak {Tec- 

 tona grandis L.), attacking leaves only, the lower surfaces of which 

 turn orange yellow due to formation of sori. Upper surface of leaves 

 may present a gray appearance due to the formation of flecks which 

 correspond to the position of sori below. 



Uredia almost plaster the lower surface, minute, subepidermal, 

 orange yellow, pulverulent. 0.2 to 0.5 mm. in diameter: uredospores 

 orange yellow, globose to ellipsoid, densely echinulate, '20-27 X 16-2'Ju : 

 paraphyses marginal, cylindric. incurved, coalescent at the base with 

 orange-yellow contents, wall up to 2.5^ thick. Telia develop within 

 uredia or separately, waxy, orange yellow, paraphyses same as in 

 uredia. Teliospores clavate. sessile, borne in clusters on basal cells with 

 orange-yellow contents, 38-51 X 6-9/*: teliospores germinate within the 



