48 Aincricdii llortirultxiral Sociifii. 



these a portion are true parasites, attacking the green leaves or other parts 

 of the Hving plant, while others are saprophytes, developing only on such 

 parts as are dead and decaying. 



During the last two years I have observed ten kinds of fungi as occurring 

 on strawberry plants in Southern Illinois, and the list can doubtless be con- 

 siderably increas'^d by farther investigation ; but so far only three of them 

 have proved injurious enough to deserve a notice under the head of " Fun- 

 goid Diseases." 



It may be of interest, a*? showing the great need of more work in this much 

 neglected but very importixnt branch of study, to note that of the ten species 

 of fungi mentioned above, five, or exactly one-half of them, proved to be 

 new and undescribed. The most important of the injurious species is Ram- 

 nlaria Tulmnei, Sacc. This occurs on wild and cultivated plants in all parts 

 of the country, from the New England Stiites to California and Oregon, caus- 

 ing the diseased condition known in different sections as rust, blight or siui 

 .scald. In order to distingui-sh it from the following species I have called 

 this the " white rust." Its presence on the leaf is usually indicated at first 

 by a reddish blotch, and later by a white spot about an eighth of an inch in 

 diameter, surrounded by a reddish border. Under the microscope this spot 

 is seen to ba covered by great numbers of minute, oblong cells borne on 

 short sUxlks. These are the spores, or reproductive bodies, and are capable 

 under favorable conditions of causing the disease to spread very rapidly. 

 On young leaves, in the spring, when the fungus is developing rapidly, this 

 red color does not appear, and the spots look as if scorched by fire. If only 

 a few of these spots are present the leaf does not seem to be much injured, 

 and the general vigor of the plant is unimjjaired. The greatest damage is 

 caused when it attacks the calyx and stems of the growing fruit, as it causes 

 them to become dry and shriveled, and the berries, if they mature at all, are 

 small in size, and have a dry, seedy look that is not attractive. 



This disease is most active in warm, wet weather, during the period after 

 blooming and before the ripening of the crop, but its eflects are most evi- 

 dent when such a season is followed by a long drought during the harvest, as 

 then the diminished leaf surface can not supply sufticient sap to perfect the 

 crop, and the dried fruit stalks prevent its free How to the ripening berry. 



As bef( re stated, this fungus occurs in all parts of the country, yet it only 

 seems to have been injurious enough to attract attention in those sections 

 where large fields of strawberries have been grown continuously in the same 

 neighborhood for a number of years. Other things being equal it causes 

 more damage toward the southern and less toward the northern border of 

 the strawberry belt. With us in Southern Illinois it has for several years 

 past caused very considerable injury, and is one of the worst of the many 

 enemies with which wc have to contend. It is, however, very hard to esti- 

 mate the per cent, of damage caused by it in any given season, as its action 

 is quite local— some fields being badly injured, while others near by are but 

 slightly aflected — and, besides, in many cases, losses occasioned by the tar- 



