WIN'E-MAXING IN CALIFORNIA. 183 



plication of sulphur, which does not stop the Peronospora, 

 for which the remedy is sulphated copper and slacked lime. 

 Let us hope that it may never trouble us, and pass it by. 



Our Chief Viticultural Officer, Mr. John H. Wheeler, has 

 recently published a very practical treatise on the "Oidium 

 Tuckeri and the use of Sulphur;" which covers the ground so 

 completely, that I take the liberty of republishing it here almost 

 entire, and am sure that those of my readers who will study 

 and follow it closely, will have little to fear from the disease. 

 I have generally found one application sufficient, either at or 

 shortly after the bloom, but the vines should be watched later 

 on, even until the berries color, and if the spotted leaves and 

 the grayish color which the fruit assumes, are observed, a 

 second application is necessary. To the varieties subject to 

 it outside of those mentioned by Mr. Wheeler, I will add the 

 Mataro, and Marsanne. Generally speaking, all very rank 

 growers are more subject to it than the medium or slow grow- 

 ers, while the /Kstivalis class is entirely exempt from its at- 

 tacks. Sulphuring is also a partial remedy against couture, or 

 dropping of the bloom or berry, (imperfect setting or fructifi- 

 cation) of which I shall treat further on. 



OIDIUM (TUCKERI) AND THE USE OF SULPHUR. 



OIDIUM.* 



The oidium (tiickeri) is a vegetable parasite of American 

 origin. It attacks all growing portions of the vine and imparts 

 to the leaves a chapped appearance, and gives them a whitish 

 or gray color. The vine, when badly affected, has a blighted 

 and sickly appearance ; the young leaves and tender parts be- 



*Frequently and improperly confused with mildow, which it is not. The 

 true mildiou is the dreaded Perono-pora Viticola, a parasite far more formidable 

 than the disease we commonly treat with sulphur and one which does not suc- 

 cumb to this or other simple remedies. 



The misnomer of the parasite common to California frequently leads to a con- 

 fusion of remedies sulphate of copper and slacked lime is the remedy for 

 mildimi but one not necessary for our oidium. 



