Polk County observer. (Monmouth, Polk County, Or.) 1888-1927, 1915-07-30
GUST CANADA THISTLE
(By H. D. scudder, o. A. C.)

from different sections of Western
Oregon. Recently this dangerous weed
has become more general in its oc-
1 currence. 1t is so persistent and per-
nicious when once fairly started in a
locality that farmers are running very
large risks to neglect the first patches
and permit 1t to spread.
The Canada thistle is a more diff
cult weed to get rid Of than the mus
tard, for while the mustard Is an an
.nual, the Canada thistle Is a perennial
living on from year to year through
| it's persistent root system. Whether
it makes seed or not it continues to
spread by means of it's underground
stems or horizontal roots. Fortunate
ly it is not a tumble weed and does
not spread with such astonishing ra-
pidity as does the tumbling mustard.
| If it did, this state would long ago
have been a sea of Canada thistles,
uninhabited by man. However, the
plant starts in the first place from
seeds brought in by grain or grass.
| Hence all seed should be examined
before sowing to avoid the spreading
of this dangerous pest in that way.
Eradication methods vary according
to the extent of the area infested.
|
They are:
First-Plants should never be al
| lowed to go to seed, as in the form of
seed they may be carried some little
distance by the wind, in the water or
irrigation bitches, or in hay, manure,
grain, etc.
| Second-When this weed occurs on
| ly in small areas it should be cut
Al. i to full Ino
and the spot completely. covered with
tar or building paper, over-lapped and
weighted with rails or earth so that
the light is completely excluded from
the plants. This can be done only on
level ground of course. On more un-
even ground very heavy covering of
straw from an old stack bottom or
manure at least l " to feet in DEPTH
when settled may be used. In either
case the covering should be left on
the spot until the fall or the following
spring it may be removed and the
ground plowed, kept thoroughly cul-
tivated until seeding time, and then
put into a row crop such as corn
checkrowed so that it may be thor
oughly cultivated throughout the fol-
lowing summer. Or in place of corn,
smother crop of buckwheat or rape
sown very thickly may be used.
Third-Where only a few scattered
individual plants are found, these
should be cut off just below the sur
face of the ground when they are in
bloom and a generous handful of
common salt thrown on the roots or
instead of the salt small amount of
gasoline may be applied
Fourth--Where the Canada thistle
occurs in a number of small patches
or clumps scattered though a field
these may best be handled either by
smothering as previously described or
by the use of sodium arsenate spray
which is made by dissolving "
pounds of this salt in So gallons of
water This solution, applied with a
small hand sprayer spread in the form
of a fine mist so that the thistles are
thoroughly covered just before they
come into bloom, will kill back the
tops to the ground. AS often as they
reappear they should be given anoth-
er spraying. This method is very sue
cessful. AS the spray is very poison
GUS, care should be taken not to in
hale it or permit stock to pasture on
the plants sprayed.
Fifth-Where the thistles are scat
tered generally over a large field but
as yet have not become firmly estab-
lished, the above methods would not
apply. In this case, after the crop
had been removed from the field the
land should be plowed in the fall and
then thoroughly cultivated with the
springtooth harrow which will turn
out the roots and bring them to the
surface where they will dry out and
die. The following spring the ground
should be plowed every four weeks
and between times thoroughly culfi-
waited with a spring-tooth up until
July, when it may be seeded to
smotherf crop of buckwheat or rape
thickly sown. Follow this crop with
fall plowing and cultivation again.
Continue the next spring, and then
put the ground into a thoroughly cul-
tivated row crop such as corn, pota-
toes, roots, rape, etc, using the noe
to get every stray thistles that may
appear.
Sixth-Where the thistle is growing
thickly in large areas and has obtain
ed a good hold, the best method is to
use a thoroughly cultivated bare fall
low. If the land has been in pasture
so that the roots of the thistle are
CLOSE to the surface, the ground may
first be plowed shallowly, then thor
oughly cultivated with the spring
tooth harrow. If fair quantities of
the roots are dragged out in this way
it would probably be preferable to
rake them off to one side and burn
them. A piece of the root of this
weed one inch long will start new
plant if the root remains in moist
soil where it doesn't dry out. This
first shallow plowing should be in the
spring when the plants are just COM
ing into full bloom. Then, after three
or four weeks during which cultiva-
ton has been given, the ground
should be plowed again more deeply
to bring up the deeper roots. Three
and even four plowings may be given
before fall if the soil is thick with
roots and the young plants continue
to spring up from time to time. The
whole success of the bare fallow
method depends on never allowing the
plants to go to seed or even to pro-
duce any growth at all above ground, |
in this way starving out the roots
which have great vitality, but which |
must die If not supplied with food
from growing leaves. Following this
cultivated bare fallow the
land may be seeded heavily in the fall |