264 



MONTHLY JOURNAL OF AGRICULTURE. 



don Gardeners' Chronicle, in which we find the following article, and who was 

 one of the Coramissioners appointed to make exanainations into this subject, does 

 not seem by any means to be satisfied either as to the real cause or as to any ef- 

 fectual remedy. He recommends /«/Z planting, for reasons which we shall prob- 

 ably give in our next. There is, he says, no danger of potatoes being killed by 

 frost in winter, in the ground. 



" Although the potato complaint already in the 

 course of several years has been known in vari- 

 ous places in Europe, it did not become the sub- 

 ject of general attention before last year, when 

 almost all over Europe it caused great devasta- 

 tion. Also this year the sickness has broken 

 out suddenly, and with great violence at the 

 same time, all over the country, and has, in 

 short time, destroyed the greatest part of the 

 parts of the potato plant vegetating above 

 ground ; but it is not yet decided whether the 

 complaint will have as great influence on the 

 tubers as was the case last year. According to 

 all accounts we have been able to collect, as 

 well as from our own observations, the com- 

 plaint this year has chiefly attacked the early 

 ripe potatoes ; but those later ripe have been 

 much more free. Although where the potato 

 complaint last year made its devastation.s, it has 

 become subject of investigation carefully con- 

 ducted by individuals as well as by Committees 

 appointed to this effect, employing large sums 

 of public money for the promotion of these in- 

 quisitions ; still, notwithstanding all that is done 

 in this direction, and that our literature has been 

 increa.sed to an enormous extent, still the result 

 of all these endeavors is comparatively nothing. 

 None of the remedies so variously proposed have 

 been effective. La.st year the attention was 

 only drawn to the illness when far advanced ; 

 its first beginniag, as well as its cause, came 

 not at all under experienced and scientific men's 

 observation. This year, when attention has 

 been early directed to the vegetative process of 

 the potatoes, it has been possible to ob.serve all 

 the phenomena of the illness from its first be- 

 ginning, and there can no longer be (hmht. of the 

 cauxe of the illnesx. It is a parasitical /'/<»;;'■»»>■ 

 belong III g to the mil dew orthreml fiiugi\\\\\ch 

 attacks the parts of the potato above ground, 

 and which shortly, in the way peculiar to fungi, 

 destroys the cellular texture of leaves, flower 

 and stem ; this fungus presents a fine cobweb 

 texture of uncolored branched fibres, and in- 

 creases with great speed by elastic germinating 

 grains, which only appear by a considerably 

 magnifying power. These germinating grains 

 are so small and so light that they are floating 

 about in the air, and descend with the dew- 

 drops on the sound plants, develop themselves 

 in few hours to threads, and destroy the leaves. 



" The sickness in the tubers appears only 

 some time after the part of the plant above ground 

 is destrojed, and shows itself by destroying the 

 cellular texture which, by the destruction of the 

 leaves, is deprived of the regular nourishment 

 which is derived from these parts. 



" The existence of the potato thread fungus is 

 like all fungi generally, only brief, and it is only 

 plainly discernible on leaves not yet blackened 

 or faded. We feel bold to assert that the pe- 

 riod of vegetation of this parasitical fungus this 

 year, has been confined to the fir.«t fourteen 

 days of August, and that it will only be the con- 

 sequences of the ravages of the fungus during 

 these fourteen days which will be lult this au- 

 tumn. 



, ''iSince it is now made apparent that the illness 

 is caused by this parasitical fungu.s, it is evident 

 that all previous suppositious about the degener- 

 ation of the potato plant as cause of tlie illness are 

 groundless, and tliat orders for seed potatoes 

 from placeshltherto free would be useless. That 

 may easily be conjectured when the cause of the 

 illness is known ; and what confirms this opinion 

 is, that Liebmann, on a journey through llie 

 island of Tionia, in the beginning of this month, 

 learned that several fanners who, at great cost, 

 had got seed potatoes from places in the United 

 Slates free from illness, had, notwithstanding, got 

 several such fields attacked as much as others 

 with the common seed. 



" The Committee feels therefore pleased that 

 already, before these experiments were made, 

 it advised not to import from Spain or the United 

 States, feeling convinced that there was small 

 probability of the complaint being from degene- 

 ration of the plant. // ix therefore evident that 

 all trials to destroy the complaint will be useless, 

 inasmuch as it originates in a parasitic funi;us, 

 the invisible germinating grain of which is car- 

 ried about in the air, and which ;Aill develop 

 itself wherever it finds a suitable .soil, viz., pota- 

 to plants, be they natives or from abroad, or 

 whether the seed tubers have been washed or 

 not in water or solutions of salt. 



"The potato complaint is an evil which we 

 hope time will heal as it hiis brought it. 



E. A. 8CIURL1NG, 



F. LIEBM.VNN, 

 A. WEILI5.\CH. 



" Copenhagen, August 31." 



It is certain that the illness is produced by this 

 parasitical fungus. 



Would it not be well, by the by, however indifferent he may himself be about 

 it, as a matter of justice and of right to him, and to the country, that Mr. Tesche- 

 macher's communication on this subject, made, bi/ request, to the " Nkw-York 

 State Aoricultural Society," as Axr back as Dec. ISio, and in which he too 

 assigned fungus as the cause for this disease, should be allowed to see the light ? 

 Was it mislaid, that it did not form a part of their annual publication ? for it is 

 not easy to imagine any paper which, in that stage of this question, could have pos- 

 sessed greater interest for agricultural science and literature — coming from such a 

 mind and such a pen, and proclaiming titen the identical opinion to which some of 



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