SPECIAL REPORT FOR YEAR. 49 



seem to be covered with fine black spots. The disease only 

 attacks the skin, and does not produce a decay, but the tubers 

 on which it occurs are apt to dry up and shrivel rapidly, par- 

 ticularly if the conditions of storage are warm. So far ordi- 

 nary methods of seed disinfection have not proven successful m 

 its control. 



There are several obscure leaf diseases of the potato which 

 have recently been recognized in Europe, and which are known 

 under the names of leaf roll, potato rosette, curly dwarf, mo- 

 saic disease, etc., which have appeared to a limited extent in 

 this country. The names indicate more or less the character of 

 the foliage of the affected plants. Potato fields, particularly 

 those intended for the production of seed should be watched 

 carefully, and all plants which show abnormal or unhealthy 

 foliage should be removed. There is reason to believe that some 

 if not all of the diseases of this type are of a physiological 

 nature, and are mo-re or less closely associated with poor seed. 

 There is also evidence that at least a part of them are carried 

 with the seed, and if tubers from affected plants are used for 

 this purpose that the crop will rapidly deteriorate. 



Diseases of the Cereals and Forage Crops. 



Three rather interesting diseases of this nature have been 

 under observation during the past year. One is a stripe dis- 

 ease of barley, which has been reported as doing more or 

 less damage in some of the western states, particularly Wis- 

 consin, and the same malady has been reported as very inju- 

 rious in certain parts of Russia. It is of a fungous nature, 

 and appears as yellow-brown stripes on the leaves. Since the 

 disease may be carried by the seed the hot water or formalde- 

 hyde treatment the same as for smut is advised. 



A new leaf spot disease- of timothy was found in Orono 

 last summer. The fungus which caused it had been previously 

 reported on orchard grass in Vermont, but so far as determined 

 this is the first case recorded on timothy. It appears in the 

 form of light yellow spots with reddish borders, and having 

 many small black dots scattered upon them. These latter are 

 the fruiting bodies of the fungus. No method of treatment 

 can be advised at the present. 



