TUBEROUS-ROOTED \ 7 EGETABLES 59 



Seed tubers thus properly prepared never shrivel, but keep 

 as plump as when lifted from the soil. 



THE POTATO DISEASE (Phylophlhora infestans) develops about 

 midsummer. Yellow spots appear on the leaves, and spread 

 quickly in humid weather, eventually assuming a dark brown 

 colour. On the under surface a mound of spores is produced. 

 The result of germination of these spores is that the young 

 tubers either remain quiescent or become putrid, according 

 to conditions of weather and other circumstances. The tubers 

 so infested are said to be " brown," are unfit for consumption 

 by man. Tubers of infested stock should not be used for 

 " seed." It has been found useful to spray the crop with 

 Bordeaux mixture (see Appendix). This work should be per. 

 formed at two or three operations, the latter if the season is a 

 wet one and the disease bad the first spraying in June, the 

 second about the middle of July, and again towards the end 

 of that month ; this prevents the spread of the disease, and 

 also prolongs the season of growth, hence the crop will be heavier 

 than a similar crop left unsprayed. As the early varieties are 

 not often materially affected, it is the winter varieties which 

 need to be sprayed. Where the area to be sprayed is not large, 

 it is well to buy the ready-made mixture. 



POTATO LEAF-CURL is in some seasons very common among 

 Potatoes. One plot may be badly affected while another close 

 by is quite free from it ; and it is likely to recur unless the 

 precaution is taken to get healthy tubers, and to plant them in 

 uninfected ground. The most obvious symptom is the curled 

 leaves, accompanied by very poor growth. If a plant is dug 

 up the reason will be seen at once, for the tuber will be found 

 to be as firm as when it was put in the ground. In other words, 

 the young plant has not been able to grow because it has some- 

 how been deprived of its natural food. 



JERUSALEM ARTICHOKES (Helianthus tuberosus). A per- 

 ennial Sunflower, native of North America, producing underground 

 shoots which swell into excellent tubers, this useful vegetable is 

 so well known as to hardly need description ; and its culture 

 is simplicity itself. In fact, so prolific is this plant, that it 

 often becomes a nuisance in the garden, for the smallest piece 

 of tuberous root left in the ground will form a new plant in a 

 spot where it is probably desired to plant some other subject. 

 The plants rise to a height of from four to six feet, rarely produce 

 flowers, but are very useful as a hedge or screen. They flourish 



