No. 11. 



Mildew, Blight and Rust. 



355 



which I barely remark, that, in common par- 

 lance, 'one swallow does not make a sum- 

 mer." 



" From the circumstance, that in the scorch- 

 ing summer of 1838 blight prevailed to an 

 unusual extent — that the lodged wheat in 

 Mr. Fox's field was sound as his standing 

 wheat, and from the few instances of winter- 

 grain being found without grass or weeds to 

 demonstrate the fact supposed to be proven, 

 together with the many fields that escape 

 blight in the worst seasons, although thickly 

 set with grass — I think the hypothesis of 

 grass sown with grain being the cause of 

 blight or rust, is not established, 



"I hold, that the prevailing cause of blight 

 in this countr3% is the sudden heat and cold 

 to which the wheat is often exposed in June 

 and beginning of July; and this I will attempt 

 to explain. Tiie wheat plants, at the period 

 of filling, naturally send up, or yield most 

 generously, the juices requisite to furnish the 

 heads with seed or grain ; this process will 

 be more or less accelerated by the action of 

 the sun, in proportion as he is mild or intense. 

 If the heat be great, and of two or three days' 

 continuance, the plants will be greatly ex- 

 cited; in this state, should the sun suddenly 

 withdraw, the wheat, exposed perhaps to a 

 merciless N. W. or N. E. wind that sinks the 

 temperature instanter some 20 degrees — the 

 chilling cold of which no instrument can fully 

 represent — animal and vegetable life being 

 only capable of realizing it — is it to be won- 

 dered that so sudden a check to the pulsations 

 of the excited wheat plants should prove fa- 

 tal ? The cold wind blowing on the head 

 and neck of the plant, chills it at the point of 

 exposure ; the head becomes languid or tor- 

 pid, while from the density of the plants and 

 the heat of the earth, there is genial heat and 

 moisture from below — the fountain that sup- 

 plied the head keeps bubbling up and flowing 

 on, but the functions of the head, reservoir or 

 condenser, have ceased, and can take no 

 more : in such a case, the fountain or conduits 

 must burst — both or either do — and hence the 

 rust that is observable on the plants, which is 

 but the outward signs of the disease that 

 preys on the vitals ivithin. After a lapse of 

 a day or days, the sun returns, and blazes on 

 the diseased head, which, having neither 

 health or moisture in it, cannot but wither 

 and die under his scorching influence. This 

 then is, I conceive, the prevailing cause of 

 blight in our climate; and if so, how remote 

 is grass or weeds from it ; so remote, that they 

 could not even aggravate the disease, but on 

 the contrary, their presence might serve to 

 mitigate it: so far from the grass keeping out 

 the heat, it helps to keep it in, when the sud- 

 den cold comes on ; and if the grain was up 

 to the chin in grass (if I am allowed the ex- 



pression) at such a juncture, it might prove 

 beneficial, by keeping the heat and moisture 

 to such a height, that should the temperature 

 to heat be soon and gradually restored, there 

 would be freshness and vigour enough, per- 

 haps, to make a recovery ; and doubtless it 

 often does recover, for we often see the evi- 

 dence of rust on the straw, v,'hile the wheat 

 is good and sound. Instead of complaining 

 that the sun cannot reach the roots of the 

 plants after a sudden or temporary cold spell, 

 which might have produced the eflect de- 

 scribed, it would be better — did he return in 

 a scorching mood — to shut him out altogether 

 for a time, if it were possible, by shading the 

 field with an awning till the wheat had re- 

 covered strength to meet him face to face: 

 just as when plants are frosted, keep the sun 

 off them, and there will not be half the dan- 

 ger. 



" Blight is not unusual in England and 

 other parts of Europe. In England it is some- 

 times occasioned by the same cause that often 

 produces it here, viz. — heavy fog, clammy 

 dew, soft rain, &c., which linger on the ears 

 when they are in a milky state, till the sun's 

 hot rays heat the whole mass: this scalding-, 

 of course, so injures the plant as to prevent it 

 performing the functions of maturation. To 

 prevent this evil, the most common practice 

 is, the same as resorted to here, the shaking 

 of the grain by means of a rope, so as to have 

 it dry before the sun makes stew-pans of the 

 shells that hold the milk or pulp — and there 

 is philosophy in this, the wet being the ele- 

 ment that causes the scald. There are other 

 plants besides wheat, which can endure great 

 heat if kept dry, but if exposed to a hot sun 

 while wet, would sicken and die; but either 

 wet and heat, or heat and cold suddenly ap- 

 plied, will prove fatal. 



"But my object will be attained, if my bro- 

 ther farmers will give this, and the paper of 

 which it is a review, a calm and candid ex- 

 amination. I do not wish to be understood 

 as schooling them into any particular prac- 

 tice ; the earth, the sky, the sun and clouds, 

 should be their monitors — nature their great 

 teacher: he who will regard their monitions 

 and teachings, will not fail to make good 

 husbandmen, nor be at a loss to determine 

 whether grass sown with grain is the cause 

 of blight. One thing, however, it may be 

 proper to recommend in addition to well-pre- 

 pared land — reasonably early sowing, early, 

 hardy, clean seed, and early cutting: these 

 are presumed to be all that come within the 

 reach of human means to provide against 

 blight; the rest must be letl to Him who 

 holds the elements in control. — Germantown 

 Telegraph. 



" Mount Airy, May 4, 1841." 



