378 
Agrieidtural Weeds. 
Now, it is not likely that each individual plant would always 
perfect the quantities of seeds above tabulated ; but the list gives 
a pretty accurate notion of the numbers of seeds which might be 
perfected under circumstances favourable to their development, 
and from it will at once be gathered the important practical fact 
that, allowing for the casualties to which seeds are constantly 
liable, yet enough would be left, where seeding is allowed but 
for a single year, to give trouble for many years after. 
It cannot be too earnestly urged that weeds be destroyed before 
their seeds are ripe, or indeed nearly ripe, as the ripening process 
is often completed by the juices in the stems, especially of pulled 
weeds : hence groundsel and thistles, when pulled and laid by, 
as we saw last year, yet ripened much seed ; and their involucres, 
opening in the sun, were wafted on the breeze to an indefinite 
distance ; and it should be recollected that one — the primary 
Lead — may ripen long before the rest, so that a tolerable weed- 
growth may follow from a delay which has allowed only this one 
head to perfect its seed. Each plant of groundsel might in this 
way be increased fifty-fold, each plant of corn sow-thistle one 
hundred and ninety-fold, and a single head of musk-thistle may 
produce an increase of one hundred and fifty-fold. 
Hence then weeding should be done as early as possible, either 
with the horse-hoe, common hoe, or sometimes the Dutch hoe, 
and, when thus early cut down, may safely be left to wither on the 
ground ; but it should be borne in mind that if any individual 
plants amongst them are shedding their seed at the time and are 
not taken away, the very hoeing ensures its safe plantation. 
It is precisely in this way that coltsfoot is often much in- 
creased. The flowers of this plant appear in spring before the 
leaves. By the time the seed is ripe the leaves become conspi- 
cuous ; the hoe is then set to work to cut down the latter, by 
which the ripened seeds are sown, when, if left, they might have 
flown away to a distance. Now it may be that the roots of the 
coltsfoot — for it is not destroyed by the hoe — are forked out 
after the crop has been gathered, but the sown seeds will insure 
that the pest shall give us some more work to do at a future 
time. The patches of coltsfoot flowers should therefore be cut 
down as soon as they appear, and by this means we not only 
spoil the crop of seeds, but cripple the growth of the plant by 
cutting off the leaf-buds. Many other instances of a like kind 
might be adduced, tending to show that a knowledge of the 
natural history of weeds is of great importance in enabling us to 
subdue them. 
Dissemination of Weeds from Wastes. — This is a matter 
that requires serious consideration, and, having once obtained 
coriect views upon the subject, should incite to prompt and 
