206 Mississippi Valley Horticultural Society. 



of special varieties, or only during certain seasons, or at certain ages of the 

 stock. But nearly all varieties of apples and pears have unusually suffered, 

 at least in places, during the last year. Even nursery stock has been singed 

 and stunted. 



It seems to me, we are first to look to the open and humid autumn of 1881 

 as an important contribution to the severe result. During this time the fun- 

 gus certainly did vigorously develop on the fading leaves, and especially on 

 the unripencd shoots of the year's growth. As the spores very readily ger- 

 minate when moistened, it is not probable that any of them survive the 

 winter on the fallen leaves. When once germinated, winter's vicissitudes 

 soon put an end to them as they do to sprouting seeds. But on the twigs, in 

 the dry air, both spores and mycelium successfully pass the winter and freely 

 grow in the spring. 



Having thus an unusual start last spring (1882), and unusually favored by 

 the remarkable lateness and wetness of the season, the fungus became im- 

 mensely developed, and, as we know, did immense damage. The outlook for 

 next year (1883), as at present indicated, is not encouraging, but no one can 

 certainly predict the results. Certain it is that the trees are noAv badly in- 

 fested, and with similar conditions a similar development may be expected. 



The important question is, " Can anything be done to reduce the dam- 

 age?" I can not, with assurance, say "' yes."' But some experiments on a 

 small scale seem to be sufficiently encouraging to plan for further and more 

 extended trials. The thing to do, of course, is to kill the fungus and prevent 

 its reappearance. From what has been said the most favorable time for 

 .treatment is in the winter when the leaves are off, and the applications 

 should be made to the young wood. 



The suggested trials are, first, pruning away any unnecessary young 

 growth and especially that mostatfected, then syringing the tree with an 

 emulsion of kerosene oil made with soap and water. To prepare this, mix 

 equal quantities of soft soap, or hard soap softened with water and heat, and 

 common coal oil; stir vigorously and for at least live minutes, then add ten 

 to twenty times the quantity of water, and again stir. The result should be 

 a uniform milky fiuid. Apply in any way so as to wet the bark of the last 

 year's growth, or, for thoroughness, that of two years' production. No fears 

 need be entertained of injury to the tenderest part of the tree if the emul- 

 sion is well made. It can be applied, if desirable, to the leaves, but there is 

 much less surface to wet before these appear, and it is much easier to 

 reach it. 



Coal oil of itself is injurious to vegetation, but when made into an emul- 

 sion, and thus diluted, no fears need be entertained about its use. Still it 

 may be in this state quite destructive to such fungus growths as that of 

 which we write. 



Sulphur has been recommended for similar use, but in this case little good 

 can be anticipated from it, at any rate, if applied in winter. The sulphur it- 

 self does not kill fungi, because it is insoluble, but the beneficial effect comes 



