THE FARMER'S MA(jAZINE. 



491 



planting is finished— damp weather being chosen for 

 doing it. 



Before leaving this notice of the manures used for 

 jiotatoes, I must not overlook the great value of sea- 

 weed. If those who can get these supplies from the 

 sea-shore fully appreciated its value, it would be more 

 regularly used than it is at present. It has a peculiar 

 value for potatoes, in cheeking the tendency to and the 

 progress of the disease. It may be used in its fresh 

 state ; but it is far more effective when mixed with 

 farmyard dung, and both allowed to rot together. Ma- 

 nures, as they may be selected, prepared, and used lor 

 the potato crop, offers great opportunities to the potato 

 grower, and by their judicious employment they will 

 materially assist him in accomplishing the great object 

 he has in view — an early and abundant crop. 



Another point well worthy of attention is the sprout- 

 ing of the seed, which 1 have already described as being 

 done in Lancashire. In this way much progress may be 

 made before the potato is planted, and this will have its 

 influence upon the time'for raising the crop. I am well 

 aware some difficulty and trouble attends its adoption on 

 a large scale, still this must not stop its more limited 

 adoption ; and when its advantages are fully known, it 

 will remain with each individual to extend its adoption 

 on a larger scale, as may appear to be desirable. So 

 long as there is any tendency to disease, so long must 

 we use every endeavour to secure early crops. Whilst 

 we are noticing the selection of seed, I must draw at- 

 tention to the connection existing between the seed and 

 its produce. For a considerable time it was imagined 

 that the produce of diseased seed was more predisposed 

 to disease than crops grown from the perfectly sound and 

 healthy seed. This opinion is not held only by a few. 

 Viewing the disease as a purely chemical change or de- 

 composition produced in the potato (by some cause not 

 definitely known), and that this change occurs natu- 

 rally in healthy seed during its growth, although at a 

 less rapid degree, thei'e does not appear to be any just 

 cause for considering that the character of the germ 

 could be prejudicially influenced thereby, except as re- 

 gards its supply of food. If the decomposition had pro- 

 ceeded so far as to cause the waste or removal of the 

 nourishment, it is clear that the germ could not come to 

 maturity, not from any tendency to disease it had re- 

 ceived, but from a want of proper food to enable it to 

 grow. 



Mr. Thompson, of Moat Hall, Yorkshire,'published 

 some interesting experiments which he tried before the 

 general appearance of the potato disease, which are re- 

 markably instructive. The following table presents, in 

 a condensed form, the results of these experiments, as 

 recorded in the Journal of the Royal Agricultural So- 

 ciety, vol. vi., p. 165. 



Black Kidneys. 

 Yeiir. Seed taken up. duality of crop. Quautity of crop. 



Year, 



1840 

 1841 

 1842 

 1843 

 1844 



Round Reds. 

 Seed taken up. Quality of crop, f Quantity of crop- 



Ripe, supposed 



Unripe 



Unripe 



Ripe 



Uuripe 



Curled 

 No curl 

 No curl 

 Curled 

 No curl 



Failing crop 

 Good crop 

 Good crop 

 Indifferent 

 Good crop. 



Ripe, supposed 

 Kipe 

 Unripe 

 Ripe 



Curled 

 Curled 

 No curl 

 Much curled 



Tailing crop 



Light crop 

 I Capital crop 

 I Verj' bad crop. 



These facts shpw most clearly (and they are confirmed 

 by other experiments) that for the production of an 

 abundant crop it is quite possible for the seed to become 

 too ripe. How this arises we may not be able fully to 

 explain ; but it is certain that when a potato has reached 

 that stage which we denominate fully ripe, and indicated 

 by its being mealy and flowery when boiled, that the 

 tissues have become Jess firm and less nutritious than 

 when they were less advanced, and consequently ad- 

 vanced appear soapy and close after cooking. 



Cultivation may be looked upon as an artificial mode 

 of forcing the growth and development of a plant, and 

 the management of our potato crop has always been of 

 this character. It would for this reason appear as if in 

 our cultivation of the potato we generally produce an 

 over-grown seed — a tuber which has been forced so much 

 that its tissues have lost strength, and this for the pur- 

 pose of table use. We must carefully distinguish 

 between this over-growth and ordinary maturity or ripe- 

 ness. The latter term, in Us true application, can 

 never be unfavourable to any seed ; but we have habitu- 

 ated ourselves to use the term " ripeness " of the crop 

 to indicate maturity for table use, rather than that earlier 

 stage at which the tuber possesses greater strength and 

 vigour. 



It would for these reasons appear necessary to select 

 seed in an earlier stage of growth than that prepared for 

 table use. To attain this result we must either obtain 

 the potatoes from poor and heavy land, where the 

 growth has not been forced, or else to plant potatoes 

 late, on purpose to produce the seed required. The 

 choice lies between these plans, and that of digging the 

 seed from the general crop before it is ready for raising. 

 The latter plan is found to be objectionable on account 

 of the tendency of the seed to sprout before it is re- 

 quired. It may, perhaps, be said that these experi- 

 ments only record the influence of the seed upon the 

 curl in potatoes, and not upon the potato disease with 

 which we are all too familiar. Mr. Thompson, in the 

 article already referred to, says, "The experience of 

 this season convinced me that curl, dry-rot, and wet- 

 rot, are one and the same complaint; that curl is a 

 mild attack of the disease, which, when violent, destroys 

 the set before it can germinate, and that it assumes 

 the dry or wet rot according to the degree of moisture 

 of the soil or season." To this I would add, that the 

 present disease is believed to be only an aggravated 

 form of the same complaint. The results are similar, 

 but rendered more certain by the presence of the de- 

 composing agent, as already explained. 



la a recent communication Dr. Lang advances the 

 opinion, that " the disease is in exact ratio to the prox- 

 imity of the tubers to the surface, and he gives several 

 singular proofs. One experiment may be recorded here 

 to illustrate the preservative power of soil : "On Sept. 



