68 FOURTH ANNUAL REPORT OP 



REMEDIES. 



Destruction of the GtAll-lice. — From what we have already seen, we 

 may justly infer that this insect cannot of itself spread from one vineyard 

 to another without going through the gall-producing phase; and a few galls 

 on the leaves are, no doubt, invariably the first signs of its advent, by nat- 

 tural means, into a vineyard not previously attacked. By natural means, 

 I mean without the aid of man's assistance, b}' which they are introduced 

 from one place to another on the roots. If these galls, therefore, could only 

 be found and destroyed, it would be one way of effectually heading off the 

 evil ; and in a new vineyard a little vigilance in searching for these galls 

 might save touch subsequent loss and labor. I shall not treat here of the 

 natural enemies of the louse, which are of such a nature that they cannot 

 be practically controlled and increased. 



Destruction of the Root-lice. — I hope next spring to institute a series of 

 experiments on the root-lice, with a view to the discovery of a practical 

 remedy. It were to be desired that others having opportunit}' and occasion 

 would do likewise. Here is an excellent chance for our different agricul- 

 tural colleges, which have greater means and facilities than any one 

 individiuil can possibly have. As a guide to such experiments, and to 

 j)rofit as much as possible by the experience of otliers, I will sj'nopsize the 

 results of trials in France. From these results, which I give below, we 

 may learn that no reliable and cheap remedy, that will destroy all the lice 

 after they have become numerous, has yet been discovered; and the best 

 advice that can at present be given is to guard against the insect's introduc- 

 tion into new vineyards by carefully examining the roots before planting. 

 If knots and lice are found upon them, the latter may be destroj'-ed by the 

 same means used against tKe Apple root-lice — i. e., by immersing the roots 

 in hot soap-suds or tobacco-water. 



Preparations of carbolic acid have, so far, given most satisfaction, and 

 I have great hoj)es of benefit from the saponaceous compound prepared in 

 this country bj' James Buchan & Co., of New York. This compound is 

 not yet manufiictured in France, where they have to use the jjure acid or 

 the crystals. 



Carbolic acid added to water at the rate of one-half to one per cent, 

 has been successfully employed, and M. Leenhardt, of Sorgues, has by its 

 use, succeeded in keeping his vineyard alive aiid bearing, while all those 

 around him are destroyed. He uses a heavy bar, thickened and pointed 

 at the end, wherewith to make two or three holes, a foot or more deep, 

 around the base of each vine. He then fills those holes with the liquid, 

 which graduall}^ j^ermeates the soil in all directions. A good post-hole 

 augur, such as we use in this country, would work more rapidl}^, with the 

 advantage of compressing the earth less, but it would do more injury to 

 the roots. 



Oid of cade. — This empyreuraatical oil, which is common and cheap in 

 France, when dissolved in any alkali (the urine of cows being good enough) 



