164 EXPERIMENT STATION. [Jan. 



an accompaniment of too rapid forcing. In some localities, 

 particularly farther south, we hear different reports concern- 

 ing its prevalence. 



Bacteriosis of Gekaxtums. 



In a previous publication of this station a short note was 

 made of a bacterial disease of geraniums occurring in this 

 State. ^ Since that time we have made yearly observations 

 on the prevalence of this disease in various sections. It has 

 appeared every year since it was first noted here in 1898, and 

 has also been reported from various other sections of the 

 United States within recent years. 



Our observations have shown that it has frequently been 

 abundant and generally distributed, so much so at times that 

 gardeners have been more or less concerned about it. We 

 have also noticed this disease in greenhouses each year, it 

 having apparently been brought in with out-door stock, al- 

 though it does not appear to be serious imder glass. Our 

 observations have shown that the trouble is more frequently 

 found on j^lants exposed to bright sunshine than on those 

 growing in shade, and is evidently more severe farther south, 

 where the light is more intense than in Massachusetts. Gera- 

 niums require comparatively little light for their best devel- 

 opment, and a strong light may favor the development of this 

 disease. 



The disease affects the leaves, causing spots to appear on 

 them. The spots are often numerous and sometimes coalesce, 

 which causes the diseased portions to dry uj) and turn brown. 

 The spots are about one-eighth of an inch in diameter, and 

 resemble blisters. No other portion of the plant is affected. 

 Examination of a large number of diseased sections shows 

 only a few bacteria present in the tissues except in those cells 

 bordering on the outer portions of the spots. 



The geranium is a very hardy plant, and one of the freest 

 from disease. No attempt has been made to treat this disease, 

 to our knowledge, and should it become more troublesome 

 some remedy for it will have to be discovered. 



1 Tenth anmi.al report, Hatch Exiierimcnt Station, 1808, page 67. 



