FUNGOID PESTS OF FOREST TREES. 



879 



Aldeb-Lb af Blibt ■ b . 

 Taphrina SadebeckU (Joh.). 



The fungus causing this disease was at first called Ascomyces Tos- 

 quinctii, but that name has now been abandoned for the above. 



It produces blisters on the upper surface of the leaves of the Alder, and 

 the naked asci or spore-sacs produce a hoary appearance. These asci are 

 truncate, or abrupt, at each end (41-55 x 15 /z), and contain eight spherical 

 sporidia, which are colourless (5- G.l /i diam.). 



Known in Germany, Belgium, and Sweden, as well as in Britain. 

 Sometimes called Exoascus Jlavus. 



Sacc. Syll viii. 8888; Phil. Br. Dm. p. 403; Grevillea, vi. p. 20; 

 Mass. PL Die. p. 91 ; Hart. & Sam. Dis. Trees, p. 188. 



Aldki; Catkin Blister. 

 H.roiiscus almitorqwu (Tul.). 



This species attacks the female catkins of the Alder, which are thereby 

 much deformed. It occurs also sometimes on the leaves, which become 

 yellowish and primrose, blistered and contorted. The asci, or spore- sacs, 

 are clavate (81-37 x 6-7 /u), with a basal cell attenuated downwards until 

 it becomes acute (11-20 x G-7 ft). The globose sporidia are small 

 (3-5 /x diam.) and numerous. 



Known also in France, Belgium, Germany, Sweden, and North 

 America. 



Sacc. Syll. viii. 3345 ; PJiil. Br. Disc. p. 403; Grevillea, v. p. 02; 

 Hart, d; Sum. Dis. Trees, p. 133, fig. 72. 



Aldkr-Root Tubercles. 

 Plcumodiophora ahii (Wor.). 



This disease of Alder roots was first called Schinzia alui, but it does 

 not appear to differ greatly from the club root of Crucifers. The roots 

 become swollen and deformed, exhibiting a mass of small tubercles as 

 large as the seed of a Vetch, or sometimes larger, and 2-10 cm. diam., 

 which tubercles contain numerous globose spores aggregated in clusters 

 or bunches (8 \x diam.) and of a mucous consistency when cut. 



Known in Germany, Poland, and Italy. 



Sacc. Syll. vii. 1569; Gard. Chron. Oct. 0, 1894, p. 398; Hart, tt 

 Sam. Dis. Trees, p. 89. 



Tree-Root Rot. 

 Armillaria viellea (Fr.). 



The blackish cord-like strands of mycelium long known under the 

 name of Bhizomorpha are for the most part connected with this Agaric, 

 which is common everywhere at the roots of trees. This mycelium con- 

 sists of blackish cord-like strands of the thickness of fine twine, which 

 creep over the roots, and the base of the trunk, close to the ground, 

 radiating on every side until they come in contact with other roots, 



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