Page:Willich, A. F. M. - The Domestic Encyclopædia (Vol. 3, 1802).djvu/458

434] rich soil, succeeded by a hot, dry summer; in consequence of which, the flower of the plant falls off; the seed is exhausted in feeding the plant; and few potatoes appear. Should moist weather occur in autumn, the plants, after being earthed, will blow a second time, and a plentiful crop of potatoes will be produced. These are, in his opinion, perfectly wholesome as food; but, being generated from the stalk of the plant after the seed had been exhausted, their vegetative power is defective, and the plants that proceed from them, will necessarily be curled.

The second cause of this disease, Mr. attributes to the forcing of potatoes, by setting them in too rich a soil. His preventive method consists in planting them early, in ridges about one yard apart, having previously spread a little manure in the trench.—They are to be set in a triangular form, five or six inches distant, and covered with soil to an equal depth: thus they will be protected from the heat of the sun, in case the weather be too dry, while they remain sufficiently apart for receiving the full benefit of the air. When the plants have attained the height of six or seven inches, he directs them not to be earthed up, but to be occasionally weeded.—By this simple method, roots will be formed in due season, and grow gradually; and, as the stalk will decay at the proper time, the sap will be left in the potatoe, and become a seed, possessing a perfect power of vegetation; so that the plants raised from it will be wholly exempt from the curl.

There prevails another opinion respecting this disease, namely, that it is contagious; but such notion has been ably combated in the 2d vol. of Communications to the Board of Agriculture; where it is observed, that whatever tends to render a crop poor and weakly, is very apt to produce the curl: hence, the disease probably originates entirely, or in a great measure, from the following causes: 1. Land, altogether unfit for potatoes. 2. Imperfect culture. 3. Small roots; or too small a proportion of strong roots. 4. Sets, taken from roots that have sprouted early, and the germs of which have been rubbed off. 5. Too small, as well as too large a quantity of dung. 6. Too deep, or too shallow planting. 7. Every external impediment that may injure new plants. 8. Too stiff ground, or such as has been pressed down too closely on the sets. 9. An unfavourable state of the weather, while the crop is young.—The result of the writer's inquiries briefly is, that, if the curl be not a disease, but merely an incidental debility, it may be prevented by diligent attention to all those circumstances; which, according to experience, are essential to the prosperous cultivation of potatoes.

It is difficult to decide, amid this difference of opinion among practical agriculturists; but, as these roots materially contribute to the comfort of mankind, we have discussed the subject at some length; and shall now concisely state those remedies which have been successfully adopted. These are, steeping the sets for two hours, in a brine made of Whitsters' ashes; changing the seed, raising new kinds from the seed, or apple of the plant; or renewing the same sorts again