590 



MONTHLY JOURNAL OF AGRICULTURE. 



Letters of Col. H. S. Eaiidall, in this Journal, does not have recourse to sheep 

 and wool growing as an important resource, to which that region is demon- 

 strated to be well adapted, it will not be for want of ample advice and illustra- 

 tion. These Letters and their author have all the requirements of experience, 

 judgment, scholarship and character to recommend them. 



MORE LAST WORDS ABOUT THE POTATO DISEASE 



(From the American Journal of Agriculture and Science, conducted by C. N. Bement.) 



Knowing no one Ijctter, if so well, qualified to throw light on tliis eubject, where that light is 

 to be reflected by Science, as Mr. Teschemacher, the author of tlic following, we take leave 

 to transfer it from the highly respectable medium in which we find it to our pages : 



I had intended to remain altogether silent 

 m future on the subject of the Potato Dis- 

 ease, for it is impossible to reply to asser- 

 tions and arguments used by Editors of Agri- 

 cultural Periodicals, themselves possessing 

 not the least practical or personal knowledge 

 on the subject, such as—" Everybody has 

 given up the fuiigus theory now," and " There 

 is nothing new on the subject of the Potato 

 Disease, except that all the nostrums pro- 

 posed have Ikiled." Equal loss of time would 

 it be to discuss experiments tried on a row 

 or two of potatoes in a garden with salt or 

 with fifty incongruous mixtures, one ingre- 

 dient of which might destroy the action of 

 the odiei- — or if any one had siicceeded, it 

 would be impossible to say to which his suc- 

 cess was owing. . I have tried salt in my own 

 garden on potatoes, and have never had a 

 single diseased tuber, but I never thought to 

 bring this forward as a decisive experiment. 



A nuitual friend whom I highly esteem 

 has urged me strongly to wiite a few lines 

 to you on the subject ; I therefore beg to 

 state : 



That the microscopic observations made 

 by nie in the autumn of 134.5, and communi- 

 cated then to the Nevv-"Vovk State Agricul- 

 tural Society, at their own request, have 

 been confirmed in 1846 and 1847 by scien- 

 tific Commissioners and Committees in almost 

 eveiy coimtry in Europe. 



That a great many experiments have been 

 tried with salt on large breadths of land, and 

 in a large proportion of the.se the potatoes 

 have been completely saved, while all around 

 were diseased. That this remedy has failed 

 in some cases in being a complete protection, 

 is all well known to me, but even here the 

 propoition of diseased potatoes was much 

 less than where salt had not been used. The 

 cau.se of this is very evident : I have always 

 stated that the salt must be in contact with 

 the disease to effect its destruction. Now let 

 any one consider in a tenacious clayey soil, 

 or in one of a light gravelly nature, how 

 (It 10) 



easily this contact may accidentally fail. My 

 conviction is more firm than ever that the 

 cause of this disease is a iiingns, propagated 

 by clouds of invisible spores, (seeds,) which 

 settle in some places and not in others, just as 

 the wind listeth or bloweth, and that wher- 

 ever they come into contact v/uh salt, when 

 they settle down they cannot vegetate. A 

 heap of diseased potatoes from two to three 

 acres will give suflicient spores to infect a 

 district five hundred miles square ; these 

 spores only ripen and become dry enough to 

 live and float in the atmosphere toward the 

 middle of the summer, and then take some 

 time to settle and vegetate ; every fungus 

 collector knows that the latter end of the 

 summer is the most favorable period for these 

 minute productions; from this we see the 

 reason why the earliest planted potatoes are 

 generally the fi-eest from disease. 



A paper has appeared within the last few 

 davs from Dr. Klotsch, of Berlin, Prussia, de- 

 tailing a new method for strengthening the 

 potato, and increasing its chance of escaping 

 disease. This new method is the old prac- 

 tice called by gardeners slopping, and has 

 been practiced by them time out of mind, on 

 cucumber, melon, pelagonium and almost all 

 phiuts ; it consists in pinching out the top of 

 a shoot, thereby encouraging it to throw out 

 lateial branches, and become strong, bushy 

 and fertile. This is a dangerous process in 

 unpracticcd hands, as if the stopping is con- 

 tinued a little too long the potato would not 

 rijien, and if begun too early would materi- 

 ally injure the plant ; it would probably be 

 much too expensive in point of labor in this 

 country. 



I hope this communication will answer 

 your purpose, and I take the opportunity of 

 stating that I am quite tired of the subject, 

 and vvill not be moved by any consideration 

 t.i engage in farther discussion thereon — let 

 those who choose, try salt as a remedy, and 

 the other leave it alone, 



Boston, Stk April, 1648. 



