Potato

In 1585 or 1586, potato tubers were brought from what is now North Carolina to Ireland on the return of the colonists sent out by Sir Walter Raleigh, and were first cultivated on Sir Walter's estate near Cork. The tubers introduced under the auspices of Raleigh were thus imported a few years later than those men tioned by Clusius in 1588, which must have been in cultivation in Italy and Spain for some years prior to that time. The earliest representation of the plant is to be found in Gerard's Herbal, published in 1507. The plant is mentioned under the name Papas orbiculatus in the first edition of the Catalogus of the same author, published in 1596, and again in the second edition, which was dedicated to Sir Walter Raleigh (1599). It is, how ever, in the Herbal that we find the first description of the potato, accompanied by a woodcut sufficiently correct to leave no doubt whatever as to the identity of the plant. In this work (p. 781) it is called "Battata virginiana sive Virginianorum, et Pappus, Potatoes of Virginia." In 1629, Parkinson, the friend and associate of Johnson, had published his Paradisus, in which (p. 517) he gives an indifferent figure of the potato under the name of "Papas seu Battatas Vir ginianorum." The cultivation of the potato in England for a time made but little progress, even though it was strongly urged by the Royal Society in 1663; and it is only comparatively recently that its cultivation on a large scale has become general.

Cultivation.

The potato responds markedly to proper culti vation, but is also peculiarly liable to disease. It is grown on almost any soil, but deep and rich sandy loarns or well drained alluvial silts are most suitable. The position of the potato crop in the rotation varies very much in different localities, but po tatoes do particularly well after a short fallow or old grass.

It is necessary to have a good tilth in the soil and it is well rec ognized that no. other crop is so good a "cleaning" crop in its capacity to smother weeds. To potatoes a supply of potash is particularly important and where farmyard manure cannot be liberally supplied a dressing of potash fertilizer should be given. Of nitrogenous fertilizers it has been shown that in England I cwt. sulphate of ammonia per acre would increase the yield by I ton.

Varieties.

There are now many hundreds of varieties on the market ; they are usually divided into First Earlies, Second Earlies, Mid-season or Early Main Crop, and Main Crop or Late Varieties. Among the First Earlies it has been found in England that among the heaviest croppers are Epicure, Duke of York, Sharpe's Ex press, Immune Ashleaf, and among the second Early and Main Crop Varieties Ally, King George, Great Scott. It is important that the seed should be free from disease and of the right "seed" size. The "seed" should be properly stored and sprouted in a cool, dry and sufficiently lighted place. The sprouts at planting should be few in number, strong and sturdy, not more than an inch long and of a dark green, purple or blue colour, according to the varieties.

Degeneration or "Running Out..

It is commonly held that a variety after being in cultivation for some time degenerates, and this was for long supposed to be an inherent physiological degeneration. It is now recognized that this phenomenon is nearly always, and probably always, the result of infection with virus diseases. (See p. 328.)