580 
The Jerusalem Potato or Artichoke. 
them by hoeing. The impossibility of taking away the whole of the 
tubers, and their power of resisting the hardest frosts of winter, is an 
obstacle almost insurmountable to the introduction of this plant, as one 
element in a regular rotation. Experience more and more confirms the 
propriety of setting aside a patch of land for the growth of this produc- 
tive and very valuable vegetable root. 
" Of all the plants that engage the husbandman, the Jerusalem arti- 
choke is that which produces the most at the least expense of manure 
and of manual labour. Kade states that a square patch of Jerusalem 
artichokes in a garden was still in full productive vigour at the end of 
thirty-three years, throwing out stems from 7 to 10 feet in length, 
although for a very long time the plant had neither received any care nor 
any manure. 
" I could quote many examples of the great reproductive power of the 
helianthus; lean affirm, nevertheless, that in order to obtain abundant 
crops, it is necessary to afford a little manure. I shall show in another 
chapter, however, that this is manure well bestowed. 
"Like all vegetables having numerous and large leaves, the helianthus 
requires air and light ; it ought, therefore, to be properly spaced. The 
original planting, of course, takes place in lines, but in the succeeding 
crops, and those which are derived from small tubers accidentally left in 
the ground, the order is, of course, lost ; it is only necessary to destroy 
a sufficient number of the young sprouts which show themselves in the 
spring, to leave those plants that are preserved with a sufficient space 
between them. When the plants are somewhat advanced, the ground 
should receive one or two diggings with the spade, and a hoeing or two 
to destroy weeds. 
" The leaves of the helianthus are used in many places as forage, the 
stems being cut a few inches from the ground ; the gathering takes 
place at different periods of the year, but probably to the detriment of 
the tubers; it may be lucrative to destine the leaves for the nutriment 
of cattle, but I believe we have to choose between the green crop and the 
crop of tubers. It is unquestionable that the premature removal of the 
green stems must prove injurious to the roots; in my own farm the 
leaves are never removed, and my opinion is that it is vastly more ad- 
vantageous to depend upon the crop of tubers alone. The tubers arc 
gathered as they are wanted ; for not dreading the frost, they may rem;iin 
in the ground the whole of the winter ; they do not require, like the 
potato, to be collected and pitted at a certain period ; they require no 
particular situation, no particular care for their preservation ; the only 
disadvantage that accompanies their being left in the ground is that 
during very hard frosts the labour required to get at them is very gr^at. 
During winter the woody stems of tlie plant die and dry up ; they are 
then useful as combustible matter; but a better use of them, perliaps, 
is to make them enter in certain proportions into the litter of the hog- 
stye ; the pith there .absorbs a large quantity of the liquid manure. 
Schwertz estimates the mean quantity of dry leaves and stems at 3 tons, 
1 cwt., 1 qr., and 13 lbs. per acre. The following quantities of tubers 
have actually been gathered in Alsace on one acre : — 
