STATE HORTICULTURAL SOCIETY. 219 



hard freeze finished what had been so nearly done before — the killing of 

 the vine. Others appeared as merely checked, without being seriously 

 injured. Upon the diseased parts myriads of spores are produced, each 

 of which gives rise to several zoospores, and each of the latter, under 

 favorable circumstances, reproduces the parasite. But they are of very 

 short life, hence the vast majority of them perish without continuing their 

 kind. Oospores are found iml)edded in the tissues of the leaves and 

 young stems, and in these situations they doubtless survive the winter, to 

 perpetuate the destructive work another year. It must be distinctly 

 understood that this disease is different from the European mildew of the 

 grape, so similar in appearance to the unaided eye, and so effectively 

 beaten by sulphur. This latter, or something very near it, is known in our 

 country, and as readily yields to the sulphur remedy as in Europe ; but 

 the destruction caused to American vines by this is very slight indeed 

 compared with the Peronospora difficulty. Sulphur, if not actually use- 

 less with it, has but very little effect. In the last year's report a mistake 

 was made as to the fungus which kills the Clinton vines, but that was sim- 

 ply by way of illustration, when speaking of the Lettuce mould. Here, 

 again, the simplest and most effective method of procedure, it seems to 

 me, by way of preventive, is to burn the diseased parts. As fast as the 

 mildew shows itself, cut away the portion and commit it to the flames, not 

 neglecting the old leaves which fall to the ground. To be effective, how- 

 ever, this would have to be generally done in the vicinity, especially in 

 the same vineyard, and would necessitate thorough work. 



Cultivated cherries suffered all summer from a mildew-like fungus 

 belonging to the genus Podosplueria, and may be species kunzei, though it 

 differs considerably from specimens of that species in my possession. The 

 May, the Morello and the sweet varieties were all injured, and in the 

 same way. The younger leaves were most affected, so that the outer ends 

 of the branches showed the most disease, and often became bare, while 

 the leaves below were fresh and healthy. Perhaps the first noticeable 

 thing was the curling and distortion of the leaves. They soon became 

 stiff, so as to break on bending, and were more or less whitened by the 

 mischief-maker. Soon they severed their attachment to the twigs and 

 fell. The mildew of the lilac leaf is not distantly related to this. The 

 first form of spores is found as simple naked spores on the white threads 

 upon the leaf; the second and true spores, eight in number, are included 

 in a transparent sack or case, and it again in a dark-walled spherical recep- 

 tacle, less in size than the period after this word. From this dot there 

 radiate about twelve curious appendages, but not so complicated as those 

 illustrated in last season's report as belonging to the lilac. 



This fungus feeds upon the surface of the leaves, its threads not pen- 

 etrating the tissues, as in the last mentioned, and can undoubtedly be 

 destroyed by application of sulphur compounds dusted upon them ; but 

 no experiments, to my knowledge, have been tried in this direction. 



This long account is here terminated, although its length would be 

 much greater if all comprised under the title and examined during the 



