3G2 



Mildew, Blight or Rust. 



Vol. V. 



For tlie Farmers' Cabinet. 

 Mildew, might or Rust — Again. 



Read before the Philadelphia Society for 

 promoting Agriculture, June 2, 1811, and 

 ordered to be printed. 



This very important subject to the farmer, 

 has recently occasioned two elaborate essays 

 that have been read before the Philadelphia 

 Society for promoting Agriculture. 



One proposes a new theory and consequent 

 remedy, or rather preventive, of this fatal 

 disease; the other attempts to controvert tiic 

 theory, and deprecates the remedy of the first 

 writer, as introducing a pernicious system. 



It is not my present purpose to defend or 

 to refute the doctrines of either of these dis- 

 tinguished agriculturists, but rather to point 

 out some errors of reasoning, and misconcep- 

 tion of facts, which I think they have both 

 been led to adopt, in their zeal to maintain 

 particular points. I may also give some 

 views and ideas which the perusal of their 

 interesting communications has brought to 

 recollection, or induced me to cull from au- 

 thors to whose works I have had recourse. 

 I must, in the first place, take the liberty of 

 correcting an inadvertence or inaccuracy in 

 the language of Col. Smith, viz. — that "heat 

 and moisture are two of the elements of vege- 

 table life :" he should have said agents, which 

 would give a more philosophic cast to some 

 of his arguments. They are most essential 

 agents of vegetation, but entirely distinct 

 from what have heretofore been considered 

 tlie elements of vegetable life. 



Mildew, rust and blight, of cereal grasses, 

 I believe to be one and the same disease, un- 

 der varying circumstances and modifications, 

 known to physiologists as Puccinia Gramuiis, 

 or animalculai of the fungus tribe. 



Col. Smith errs in his theory of blight, by 

 limiting it in a great measure, if not entirely, 

 to the single cause of grass and weeds 

 amongst the grain. 



The agents which give energy to this 

 parasitical fungus are many ; and perhaps, as 

 Mr. Gowen asserts, our atmosphere or cli- 

 mate is the most active. 



With this reservation I am willing to go 

 hand in hand with Col. Smith, in assigning 

 as one of the predisposing causes, an undue 

 portion of grass and other vegetation existing 

 and drawing nourishment from the ground 

 and the surrounding atmosphere at the same 

 time as the wheat, a substance which re- 

 quires great nutritive force to carry it vigor- 

 ously through the ripening process. Admit- 

 ting the correctness of this principle, and T 

 think it will bear the test of scrutiny, tlie true 

 practical inquiry for the farmer is — how far 

 can wc dispense with or abate the evil ! 



Before proceeding farther, I must acknow- 

 ledge myself under the ban of Mr. Gowen's 

 rather tart language, when he deprecates aa 

 "visionary the idea that grass and weeds 

 tend in the remotest degree to occasion rust 

 in wheat." 



Tliis " idea" of Col. Smith's is probably 

 new, but nevertheless may be correct, and 

 might be arrived at by implication from vari- 

 ous eminent writers, who also su.stain or give 

 countenance to his remedy as the best mode 

 of cultivating wheat. The old pioneer of 

 Scotch husbandry, Sinclair, recommends the 

 eradication of all weeds, which are likely to 

 generate or produce rust. Le Couteur urges, 

 in emphatic language, the perfect cleansing 

 of the ground, and for this purpose prefers 

 drill cultivation, which he thinks more than 

 compensates for the additional expense, by 

 the increased and more healthy yield. He 

 says, "Clover and rye grass are sown at the 

 cost of several bushels per acre on the wheat 

 crop, and that his practice is to sow grasses 

 immediately after tlie grain has been har- 

 vested, which has been Ibund to answer re- 

 markably well, though at the expense of one 

 additional ploughing," and quotes Sinclair to 

 show that September is generally the best 

 month for sowing grass-seed. 



In "British Husbandry," vol. 2, page 159, 

 to prevent diseases of grain, it is recommend- 

 ed to preserve a free circulation of air, and 

 especially drilling the grain instead of sowing 

 it broad-cast. I would not be understood as 

 deciding that Col. Smith's doctrine is correct, 

 and should be adopted, namely, that grass 

 being injurious and promotive of rust, sliould 

 not be sown with but after the grain. It is, 

 however, an important question, and ought 

 to be studied and observed with much atten- 

 tion. 



I may hereafter trouble the Society with 

 some reflections respecting the present order 

 and succession of crops. Both Col. Smith 

 and Mr. Gowen are, in my estimation, very 

 unscientific in reasoning on the action of 

 grass growing at the roots of grain. One 

 tells us that "the moisture is increased by 

 such vegetation," and the other that "grass 

 and weeds arc of service to shade and protect 

 the crops in dry weather." Now my reading, 

 observation, and practice have taught me that 

 grass and weeds amongst crops increase the 

 dryness of the ground, and that to keep the 

 surface perfectly mellow and clean, counter- 

 acts the efl^ects of drought; and, in fact, grass 

 itself suffers more in dry weather under the 

 shade of trees, than in the sunshine. 



Mr. Gowen's potatoes would assuredly be 

 destroyed by weeds in dry weather, though 

 both might vegetate in a wet season; and his 

 idea of sowing grass to prevent the growth 

 of weeds, is a pretty bold assertion for a 



