ON THE CURL IN POTATOES. 3g7 



It maybe proper to observe, that the produce of the Perhaps the 



curled potatoes was taken up before being too ripe, and curl mi S ht be 



, . . , , . * , , removed by 



replanted with the others: 1 cannot say that the disease taking up the 



was removed, but they did not get worse. Perhaps re- tubers e3 - r] Y- 



planting them in very highly manured land, for several 



years, might have a good effect: but unless it were for the 



sake of reclaiming a favourite variety, the experiment is 



hardly worth making. 



Having trespassed so long on the attention of the Society, 

 I shall only beg leave to suggest a few simple rules, which, 

 if attended to, will, I am humbly confident, soon entirely 

 banish the disease of curl from the country. These are, 



It To procure a sound healthy seed-stock, which cannot Means of pre- 

 be relied on, unless obtained from a part of the high country, renting the 

 where, from the climate and other circumstances, the tubers 

 are never overripened. 



2. To plant such potatoes as are intended to supply seed- 

 stock for the ensuing season at least a fortnight later than 

 those planted for crop, and to take them up whenever the 

 haulm or stems become of a yellow-green colour: at this 

 period, the cuticle or outer skin of the tubers may be 

 easily rubbed off between the finger and thumb. 



3. To prevent those plants, that are intended to produce 

 seed-stock for the ensuing year, from producing flowers or 

 seeds, by cutting them off in embryo ; taking care, how- 

 ever, to take no more off than the extreme tops, as, by 

 taking more, the crop may be injured. The best mode of 

 doing this, is with a common reaping-hook, or light switch- 

 ing bill. Two boys or girls may do an English acre in two 

 or three days. 



Nurseries, Leith Walk, 

 6th of March, 1810. 



References to Plate VIII, Fig. 1. 

 A The ripened or dry end. 

 B The waxy or wet end. 

 a a The cuts or sets from the dry end. 

 b b The cuts or sets from the umbilical end. 

 c c The umbilical cord or connecting radicle. 

 d d The real roots of the plant. 



II. Electric 



