The Manitowoc pilot. [volume] (Manitowoc, Wis.) 1859-1932, 1913-07-24
CONTROLLING CANADA TuISTLES.

States from Maine to Virginia, west to
North Dakota and Kansas, and in the
Pacific Coast States from Washington
to northern California 1t also seems
to be spreading in the Rocky Mountain
States. But few reports have been re-
ceived of its presence in the Southern
States and it is very probable that this
weed will not be serious pest in that
region.
The Canada thistle may be identified
by its erect, above-ground stems, to 3
feet in height, its lobed aud very spiny
leaves, somewhat downy on the under
side, and its flowers, which are gener-
ally rose purple, one-half to seven
eighths inch in diameter, clustered at
the ends of the branches.
Being perennial plant, the Canada
thistle propagates itself both by it's
underground parts and its seeds. The
| character of the underground growth
must therefore be understood in or
der to attack the weed intelligently.
The root, which varies in size from
one quarter of an inch or more down
to very small feeding rootlets, branch
es and spreads in all directions more
or less horizontally. The depth of this
root varies from few inches to a few
feet below the soil surface, depending
on the kind of soil in which it has been
formed. From any point along the root
buds may form and send up root shoots,
which appear above the soil surface as
stems or tops CT the plant. At any
time during tie growing season shoots
in all stages of development can be
found, from the most advanced down to
those just starting from the roots.
The Canada thistle spreads into new
localities, from farm to farm, and even
from field to field on the same farm,
largely by it's seeds. These seeds
are smooth brown, about one-eigth
of an inch long, and nearly cylin-
drical, being little pointed at one end
Each seed has a tuft of hairs called
pappas. The time of seeding extends
from July to October. This weed is
peculiar in that only few OF the plants
produce seeds that are able to grow.
1t is not known just what the conditions
are which govern this. In most in
tested areas enough perfect seeds are
formed to;greatly increase the nuisance,
SO thas the farmer is not justified in
permitting the blossoms to nature.
The principal ways in which the seeds
are scattered are as follows:
Wind and water.-After the seeds
mature they are easily detached from
the heads by the wind and are scatter
ed over the surrounding country. The
feathered pappus bears them up, thus
permitting them to be carried consd-
cradle distance. They are also carried
by run-otf water down hillsides and by
streams. Transportation by water be-
comes special danger in irrigated dis
tricts, where the bitches and laterals
readily carry the seeds over the land.
Small grains and straw.-Mature
thistle seeds are often harvested with
small grains, but are usually separated
from them in thrashing. 1t is often
advisable, however, to reclean such
small grain as is to be used for seed,
especially in the case of oats. The
thistle seeds are car ried over into the
straw-stacks and from them through
the manure to the fields; but If such
manure is left in piles for several
months practically all the seeds will be
decomposed. Harvesting machines of.
ten carry the seeds to other field and
threshing outfits carry them from farm
to farm.
Hay. If hay is cut sufficiently early,
when the thistles are just starting to
bloom, there,will be no danger of their
maturing seed. Many farmers let their
hay stand too long, not only diminish
ing it's value but permitting the thistle
to form seed.
After U,is Weed has obtdined toothoh
The best rag to eradicate IL is to paeremt ii
from sendinouD top on Underground grouh
phich causes the roots to die. This Is the
basic principle uhich must be kept IN mind
at all t.mes. The top Of the plant series
much The same purpose as the l,tngs of an
in,als, so that i the plant is continually de-
p,fred Of that ritdl part il must soon die.
There are number Of ways of keep
ing down the top growth; there is no
one best way for all cases. The best
method for each case will depend on
the farmers rotation and convenience.
Any practicable method will do.
The man, therefore, is of far more
Importance than the method. Many
farmers make start to kill the thistle,
but abandon their efforts too soon. 1t
is probably no exaggeration to say that
50 per cent of the efforts to kill thstles
are failures. Often the campaign is
abandoned when success is in sight, and
the thistles soon recover One great
trouble is that farmers are looking for
too easy a method there is no "prim-
rose path" to thistle eradication. II,
however, the farmer understands the
basic principle as given above in italic
type, decides on a systematic plan, and
then faithfully 'sees it through to a
finish" he will free his farm Of the
thistle, and this will be accomplished
without a great amount OF labor or ex-