|—_—_—— 
524 
and excrescences of every conceivable shape. A 
naked fallow is a remedy for it; but all applica- 
tions to the soil and plant have been ineffectual. 
—The wire-worm is a sad enemy.—The swarms 
of aphides, or plant lice, severely injure the tur- 
nips, and from the smallness of their size are 
often unobserved. In 1836 they committed ter- 
rible ravages. They suck the juices of the plant, 
and appear in countless numbers. They are both 
oviparous and viviparous, and increase with 
amazing rapidity. Happily they are always fol- 
lowed by swarms of lady-cows, which feed on 
them, as well as insectivorous birds which de- 
stroy vast numbers. No remedy can be applied 
with any probability of success. Hvery farmer 
should carefully protect swallows, red-breasts, 
&c., which are great destroyers of the aphides.— 
Slugs, especially on newly-ploughed soils, are 
great devourers of the turnip plant in all its 
stages. Ducks will devour them, but always 
injure the plants. Three bushels of quick-lime 
per acre, scattered over the plants early in the 
morning, when the slugs are active, is a certain 
method of destroying them.—Perhaps the very 
best preservative from all the diseases is liberal 
manuring, adapted to the soil, thorough cleaning 
of the land from weeds, and in short pursuing 
whatever measures are best for securing a full 
crop. The vigour of the plants in such cases, 
and their rapid vegetation, often enable them to 
overcome many serious attacks, 
The Produce of Turnip Crops—An ordinary 
or average field turnip, of the kinds most com- 
monly cultivated in Britain, weighs about 6 or 
7 pounds; and one of a large variety, grown 
under the most favourable circumstances, weighs 
from 20 to nearly 30 pounds. A calculation has 
been made that one ounce of turnip seed con- 
tains from 15,000 to 16,000 seeds,—that there- 
fore each seed weighs only about a 15,000th or 
16,000th part of an ounce,—and that, when de- 
veloping itself into a plant whose cauline bulb 
has an average weight of about 6 or 7 lbs., it 
must, on the supposition of an uniform increase 
of substance during the period of growth, ac- 
quire 15 times its own weight in a minute; and 
by an actual experiment, made on peat soil, it 
was found that turnips, during the period of 
their growth, made an average daily increase of 
15,990 times the weight of the seeds from which 
they sprang. “It is not, however, only the size 
and weight of the root,” remarks a popular 
writer, “which renders the turnip crop so pro- 
ductive. The number contained in a given 
space, with reference to their size, is very great. 
Some writers speak rather marvellously on this 
subject; but it is generally thought to be a good 
crop when a turnip is obtained from each square 
foot of ground. Mill considers an average crop 
to be 11,664 roots per acre, which, at 6 lbs. each, 
will be 69,984 lbs.” 
The amount of any one turnip crop, however, 
is powerfully affected by the condition of the 
TURNIP. 
soil, the stage of the rotation, the kind and 
quantity of the manure, the method of culture, 
the character of the climate, the prevailing 
weather of the season, and the particular variety 
of the plant. A light soil will never produce a 
maximum crop of Swedish turnips; nor a heavy 
soil, a maximum crop of common turnips; nor 
an ill-tilled soil of any kind, a maximum crop of 
either. A suitable soil in a freshly manured 
state, or at the commencement of a rotation, will 
produce, on the average, from 28 to 33 tons per 
acre; while the same soil, after an intervening 
crop from the manuring, or in the second year 
of a rotation, will not produce, on the average, 
more than from 6 to 8 tons peracre. Different 
plots of one field of strictly homogeneous charac- 
ters, treated in exactly the same way, and crop- 
ped from one specimen of seed of one variety of 
turnip, but fertilized with different kinds and 
composts of good manure, will, as we showed in 
the section on the manuring of the turnip, yield 
very widely different produce, both in quantity 
and in quality. The drill culture, in any given 
circumstances, will always produce a better crop 
than the broadcast culture; and the raised-drill 
culture, in adverse seasons, will generally pro- 
duce a better, and sometimes very much better, 
than the large-drill and flat-surface culture. 
The comparatively cool and moist climate of 
Scotland and the north of England constantly 
produces a much larger average turnip crop 
than the comparatively warm and dry climate 
of the south of England; and for the same rea- 
son, a hot and droughty season will diminish 
the average in the former districts, and a cold 
and wet one will increase it in the latter. As 
to the comparative weight and size of the roots 
of different varieties, “it has been found, after 
repeated trials, that sound green-top yellows, of 
7 or 8 lbs. weight, gave, as their highest average, 
32 cubic inches per pound; which may be as- 
sumed as a medium standard of solidity or den- 
sity, and being compared with the actual weight, 
will afford a just criterion of their value, and a 
correct idea of their sizes. Thus, by dividing 
the number of cubic inches contained in any 
bulb by 32, (the remainder being halved for 
16ths or ounces,) the quotient gives the number 
of pounds and ounces that should be of the 
standard solidity; the actual weight of the bulb 
will indicate the solidity, which wili either be 
at, or above, or below the standard—as the num- 
bers of the weight are equal, or greater, or less 
than the numbers of the size.” Specimens of 
some of the chief varieties, grown upon different 
soils and carefully selected, were put to the test 
on this principle, at Messrs. Drummond’s estab- 
lishment in Stirling, and gave the following re- 
sults :-— 
Weight per standard. Actual weight. 
Swedish turnip, AV 8lb. 112) oz 13 Ib, 12 oz. 
Dittormas wee O Ib; 5) oz 13 lb. 8 02. 
Green-top yellow, . 16 lb. 15 |b. 
Ditto, -» 15 Tb. 14 1b. 
| 
| 
