1907.] 



Projjlkms ix Potato Grow i no 



69 



Cross-ploughing. — Another question requiring to be tested is the 

 advantage 1 or disadvantage of cross-ploughing land for potatoes in 

 February. It is probable that this operation is beneficial on the 

 best potatosoils, which arc of a friable character, provided that the 

 land is fairly dry when it is carried out. But where the ];md is 

 at all heavy, there is good reason to question the advantage of 

 ploughing a second time in the latter part of the winter or in the 

 early part of the spring. In most heavy-land districts experienced 

 farmers are averse to such ploughing for spring corn or mangolds, 

 because soils containing much clay are never in so finely divided 

 a condition and accordingly so drought-resistant as when they 

 are ploughed finally in the autumn, and worked only by culti- 

 vators and harrows in the spring. It is true that occasionally 

 when drought follows a wet period in the spring, before the land 

 is sown, it has been first " run together " and then dried into a 

 compact mass which no implement but the plough will break 

 up satisfactorily. In such a case ploughing is adopted as the 

 less of two evils, but only so. 



To say the least, it is not obvious why a practice avoided on 

 heavy soils as far as possible for spring corn or mangolds should 

 be advantageous for potatoes. Unless hard frost follows the 

 cross-ploughing done in February or early in March, retentive 

 s< »ils are apt to prove cloddy when cultivated for potato-planting, 

 and consequently to let a possible drought penetrate to the depth 

 cultivated when the crop is growing. 



It is further to be observed that the relative advantages on 

 different classes of soil of growing potatoes in drills and on 

 the Hat respectively have not been tested by any con- 

 siderable number of trials, so far as can be determined by public 

 reports. 



Maturity of Si\\t. A> already incidentally indicated, the asser- 

 tion that immature seed is of superior productive power to mature 

 seed needs to be tested by .1 g< >od number of precise experiments. 

 There an 1 certain considerations which appear to tell against this 

 assumption. It will not be questioned that potatoes of seed-size 

 are usually less mature than the full-sized tubers from the same 

 crop, and yet the latter are commonly the more productive, 

 although not the more profitable to use as seed, unless when 

 potatoes are very cheap. Again, during the past season, seed fr< 'in 

 Ireland pr< >ved m< >re productive than seed fn >m So >t land in several 



