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I have examined the samples sent on various occasions, and with every attention, using a lens of ten diaineters. I likewise examined the dirt that was in the parcel to see if I could discover the cause of the disease that the vines represented by the samples are suffering from, without obtaining any great result.
Further, I must confess that the examination of plants taken up without the necessary care and precautions, dry and mutilated by the journey, cannot be expected to give satisfactory results.
To attain this it is necessary to study the living plant. cause those that seem most characteristic to be taken up with every care to obtain even the smallest root, take note of all that refers to the disease, age of the vines, mode of treatment and irrigation, description of soil and subsoil, and to pick on the spot those parts that should be examined later on in the laboratory, and to preserve them so that they may undergo no change.
I have arrived at the following results :
Samples from Talca.-Taken from the vineyard of Mr. Otto Schleyer. The plants have none of the tender rootlets; the thick ones that are present show here and there a swelling. The trunks and branches show nothing particular, beyond a sort of ring which exists in one of the plants at the junction with the stem, of half the circumference,—the origin of which I cannot explain, as it does not seem the work of an insect. The swellings here observed on the roots cannot be the work of the phylloxera, as this chiefly attacks the finest suction roots, which quickly succumb to the devastation of the insect.
Samples from the vineyard of Mr. Juan Pinasseau.—These samples are also without the small suction roots. The others present, in various places, the bark raised and loose; removing this, I found underneath a black powdery mass, which appears to result from the rotting of either the external part of the wood or the internal part of the bark, and I have been unable to find in the putrified mass any vestige of insects or other animal. I have not observed any anomaly in the stems, branches, or leaves of these samples. The stripping of the outer covering of the bark in the samples of vines from Talca is what may be observed in all vines; and the inequality of the roots, and the knots in the stem where the leaves break out, and which are covered with bark, are normal.
Samples from Quirihue.—These samples are short thick pieces, and in which there is not much to be seen. The few fine roots that are to be seen on these samples show absolutely nothing of the swellings which result from an attack of phylloxera on the roots. The swellings that are to be seen in the thick roots and stems are such as may be seen in many plants in complete health. I have been unable to find any degeneration in the bark, which is usually seen in many unhealthy vines, such as excrescenses, exuberance of cellular tissue, and other lacerations, other than those that are normal in the bark of the vine. I have not been able to see anything anomalous in these vines.
Summary. In all the samples which I have examined, taking ample time, and to be certain I have gone over them several times, I have not found anything that can be compared to the phylloxera; but, as I have pointed out in another part of this report, dry samples taken up without due care, such as I have before me, are not sufficient to give ample proof of the existence, or nonexistence, of phylloxera. It is necessary to study the plants in their places in the vineyards.
The different articles published in the periodicals lead me to think that we have not the phylloxera to deal with in this case. I am more inclined to think that special conditions of soil and humidity have originated the disease. There is in Germany a disease of the vine called “Gelbsucth” (Jaundice), which seems to have some similarity to the disease among the vines of Talca and Quirihue, of which the well-known Prof. Taspemberg says, in his pamphlet on phylloxera :-“The jaundice consists in the leaves turning yellow, short shoots, and the bunches weak, with small fruit. It is found principally in cold clayey soils, that retain the moisture for a long time, or in soils which contain much sulphate of iron in the waters that collects in it. This salt is deposited when the water evaporates in the fissures in the ground in the form of a white powder, which sometimes is mistaken for saltpetre. The disease appears when the ground is worked at unseasonable times—that is to say, during or immediately before a heavy fall of rain, which causes the formation of a hard crust which prevents the air entering the soil.
"A second rainfall in dry weather may remove these defects. The turning yellow of the leaves takes place uniformly in all places from the top of the plant towards the lower part, but not from the lower towards the upper part, nor with isolated blotches as is seen in the phylloxera.”
I think the time has arrived when the Government should consider the appointment of an inspector of vineyards, or consulting pathologist, with head-quarters in Santiago, where a small microscopic laboratory could be arranged, supplied with the necessary literature, and with an annual endow. ment to subscribe to the works that may be published on pathology of the diseases of the vine.
This officer should have no other duties but those mentioned, and should apply himself exclusively to the study of the diseases of plants, chiefly those of the vine; besides, he should go to such places as the Government sent him to carry on investigations on the spot where any disease appears, and thus enable himself to get such information as is required of him. For such a post a botadist should be chosen, as in order to obtain useful results a person is needed that has the knowledge of vegetable anatomy which an ordinary person does not possess.
But the Government should go even further than this, and submit to the Chambers a law that would compel every proprietor to give the inspector of viderards access to every part of his estate.
I'believe that the comparatively small cost that such a post would entail would be amply repaid by the result of the services that would be rendered.
have received I could not accomplish much.-I am, &c., &c.,
The Sulphate of Copper in Diseases of the Vine.
(From the Doletin de la Sociedad Nacional de Chile.)
TRANSLATED FROM THE SPANISH BY H. CAMBRIDGE.
The constant application of sulphate of copper as a remedy against the cryptogamic diseases of the vine, which is being practised with greater faith and departure every day, gives rise to the thought, and induces one to ask, to what point and in what quantity will its use be harmless to the life of the plant, and what will be the maximum of that salt that it will be advisable to impregnate the soil with that the vine is rooted in.
Mr. Viala, so learned a naturalist and viticulturist, answers these questions in the account he has lately given of his many experiences and experiments undertaken to determine that maximum, and to ascertain if the quantities of sulphate of copper that accumulate in the soil as a result of this treatment at the end of a certain time will hurt the vine in its physiological functions.
In one of the series of comparative experiments he took two vines, one to be subjected to irrigation with a pure solution of sulphate of copper, and the other was to be allowed to grow under the ordinary conditions, watering it with the same quantities of water as the first, but without the sulphate. Each plant was set in a large vessel that would hold the liquid that the plants were watered with, the excess passing through various orifices made in the bottom of each vessel into the ground.
The drainage collected from the plants watered with the sulphate always showed the characteristic colouring of the sulphate in solution, notwithstanding it had filtered through a good thickness of soil which clearly showed the richness of the concentrated solution.
After the watering with the solution has ceased, and the plant was watered with pure water, the liquid with which the soil was saturated to some deptb showed the colouring of the sulphate solution.
The quantity of sulphate given to the ground with these waterings, in such quantities of water that would not injure the plants by excessive moisture, was 200 gramos ('45 lb. averd.) No hurtful change was noticed in the life of the plant comparing its growth with the vine that was under normal conditions. The leaves appeared and unrolled themselves normally and regularly; they were of a beautiful green colour, much more pronounced than in the ordinary plant, and with greater expansion of surface.
Several leaves of the lower branches dried or turned yellow, but this was also the case with the other vine. The flowering of three bunches before the formation of the fruit took place with due regularity and in the usual time, and, in fact, there was no hurtful symptom noticed, but the treatment served to have given greater vigour to the plant.
The 200 gramos of sulphate of copper dissolved in each pailful, or quantity of water given the vine would be at the rate of 20,000 kilogramos
(44,100 lb. aver.) for the solution per hectaria (2:471 acs.), and taking into account not only the surface, but the depth of that quantity of land, taking for granted that the depth to which the roots spread is 50 centimetros (16 inches)the quantity required would be 50,000 kilogramos (110,250 lb.) for each hectaria (2} acs. abt.)
It is clear that the rain and irrigation waters, in their passage through the soil, illimenate or draw away a large portion of this mass of salt. Giving it, as is done annually to the vineyards for the cure of " mildew,” four treatments with leak of 5 lb. of sulphate of copper, at the rate of 200 litros (176 Impl. qts.), and of 600 in the other three, the maximum quantity of the salt used would be 40 kilogramos (88 lb.) per hectarea.
Well, now from this quantity to that used by Mr. Viala in his experiments, there is such vast difference that by the treatment of the criptogamic
diseases, to give the ground the quantity of sulphate given it by Mr. Viala, , it would require a period of 500 years, supposing the rains did not take any of it away, but to apply the quantity indicated to the depth of soil 50 centimetros (161 in.) per hectarea, as given above, the treatment would have to be followed during a period of 1,200 years as applied at present, and yet, according to the belief of the said naturalist, all these enormous doses of sulphate would not be prejudicial to the vine.
Methods adopted in the Island of Elba to
eradicate the Phylloxera.
(From the Boletin de la Sociedad Nacional de Agricultura, Chile.)
TRANSLATED FROM THE SPANISH BY H. CAMBRIDGE.
THE Italian Minister for Agriculture has been informed from the Island of Elba of the fact that has great significance to viticulturists, and which may prove that at last positive results have been arrived at in the problem of the destruction of phylloxera.
The scourge commenced to destroy the vines on the island in such a rapid manner, that the producers actually found theinselves in a state of bankruptcy.
M. Laur d'Angelo, a vineyard proprietor, very learned in agriculture, and who was the first who six years ago commenced to treat his plantations with sulphate of copper to preserve them from " peronospera," "oidium,” and from the decaying of the leaves, a disease very prevalent on the island, had noticed that his vines planted on land round which the phylloxera had raged during four years, and which had devastated the neighbouring plantations, had not been attacked by the parasite.
This fact so entirely opposed to the usual rapidity with which the evil is propagated attracted his attention, and he endeavoured to ascertain the cause.
After a considerable number of experiments he was enabled to verify that the sulphate of copper applied under the form of a liquid preparation was sufficient not only to sterilise the phylloxera, but that it also made the surroundings noxious to the existence and propagation of the said parasite.
This is how he explained the matter:-After the spraying and dusting with sulphate of copper, the latter was beaten into the soil by the rains of autumn, winter, and spring, and so enriched the ground with a certain amount of the sulphate of copper.
This poisonous agent would make the immediate surroundings noxious to the existence and reproduction of the parasite nestled among the vine roots.
Special experiments made by M. d'Angelo on vines that had been infested with the phylloxera, and at the time all but dead, have proved that once the infected vines were treated by digging in the sulphate of copper round them, they recovered life and vigour, and this fact gives greater value to his statements.
The method adopted by M. d'Angelo consists in giving the vines two applications in a liquid form, and five in the form of powders. For the liquid treatment he uses lime 1 per 100, and sulphate of copper 1,800 per 100. As regards the treatment with the powders, two are made at 3 per centum of sulphate of copper, and three are made at five per 100.
These experiments have been considered by the Director General of Agriculture in Italy, and it is expected that this system will be generally adopted, and thus save the Italian vineyards from the pest.