XX Report ov the Botanist. 



•n. 



on mature plants of phlox, pyrethrum, snapdragon, raspberry, 

 lamb's (piarters, pigweed, and tumble weed. Field observations 

 liave been made upon these diseases so far as possible. The parasi- 

 tism of the fungus has also been studied as much as time and the 

 very limited greenhouse facilities at my disposal would permit. 

 The work of '' cross inoculations " must be extensively conducted. 

 In addition, most of the various form of the fungus are being studied 

 in laboratory culture. In general, Rhizoctonia is a damping-off 

 fungus, and a cause of certain root and stem diseases of plants. It 

 is usually to a considerable extent dependent upon moist conditions 

 for its rapid spread and propagation. Effective means of preven- 

 tion have not been found, except in the sterilization of greenhouse 

 or potting soil in the case of choice ])lants. 



An important disease of the currant in the Hudson Yalley has 

 received much attention, and five visits have been made to that 

 region in order to study as far as possible the conditions governing 

 that disease in the field, and the effects of it upon the host plant. 

 The fungus has been isolated and studied in the laboratory, and 

 numerous inoculation experiments have been made. This disease 

 lias hitherto received only the most casual attention, and no success- 

 ful attempt has previously been conducted to determine the fungus 

 causing it. A bulletin will shortly be issued setting forth the pres- 

 ent state of our knowledo:e concernino; this disease. 



x\n inextensive survey of the hop diseases in the hop-growing 

 section of the State, particularly at Water vi lie, has resulted in find- 

 ing one very destructive malady. Innnediately previous to the time 

 of picking and harvesting the hops in this region, the vines in 

 almost every yard were found to be more or less severely affected 

 with a leaf fungus, a species of Cylindrosjyorium. This fungus 

 attacks and injures the leaves first, and then its injuries extend to 

 the hops themselves. When the leaves alone are affected, merely 

 the general vigor of the vine is reduced ; but when the hops are 

 diseased, they turn brown, present a poor appearance and much 

 bleaching is necessitated in order to render them marketable. 

 Sometimes the fungus causes the hops to shatter so badly that they 

 are almost worthless. A thorough studv of the fundus diseases of 

 the hop in this State would be very desirable, 



