438 DISEASES OF CULTIVATED PLANTS 



which infect the young leaves and shoots. All such shoots 

 should be removed, and all diseased leaves should be collected 

 and burned. 



Laubert, R., Zeitschr. Pflanzenkr., 14, p. 257 (1904). 

 Rostrup, Plantcpalotogi, p. 580. 



Witches' brooms on paulownia. A very serious disease 

 attacking Paulozvnia tomentosa (H. Bu.), caused by Gloeo- 

 sporium Kaivaka?nii (Miyake), is recorded from Japan, 

 where the host is now extensively cultivated on account of 

 the excellent wood, which is largely used for cabinet work, 

 musical instruments, wooden clogs, etc. Seedlings and 

 young trees are attacked, the first symptoms appearing on 

 the leaves and young branches. On the upper surface of the 

 leaves light brown spots with a darker margin appear, and 

 the leaf becomes perforated at the diseased points. The 

 principal seat of the disease, however, is young branches and 

 petioles and principal veins of leaves, where the spots are 

 most abundant. First year's seedlings when attacked usually 

 die during the season. From the second year onwards those 

 plants that are not killed outright produce a number of 

 adventitious buds in the axils of the leaves, and these grow 

 into witches' brooms with small, pale green, curled leaves. 

 These brooms are perennial. 



The conidia ooze out in roundish, light, salmon-coloured 

 masses, linear, linear-oblong, or lincar-clavate, outline some- 

 what irregular, straight, or slightly curved, hyaline, 10-13 X 



2-5-3/*- 



Chlamydospores readily produced in water or nutrient 



media, ovate or elliptical, one-celled, wall smooth, thick, 



black, 6-5-16 x 5-7 \l. 



The disease assumes an epidemic character where pure 



plantations of large extent are formed. 



Kawakami, On the Hexenbesen of Paulownia tomentosa. 

 Tokio, 1902. 



Almond anthracnose. Dr. Briozi has described an almond 

 disease caused by Gloeosporium amygdalinum (Briozi). The 

 green fruit is attacked and its growth arrested. The fungus 

 forms circular spots covered with concentric tufts of fruit. 

 The young shoots are less frequently attacked. 



