Kari Lewis, MSU Extension - Glacier County
It seems it’s the year for dandelions this year!
Dandelions
are actually a perennial weed, and if not controlled, each plant's crown and
root system will remain alive after the leaves have died in fall. Plants
overwinter and begin growing again in early spring. Dandelions blooming in
early spring do not result from newly germinated seedlings; but instead they
are the result of the previous year's overwintered plants. Therefore, the ideal time to control the
dandelion, since it’s a perennial weed, is the fall. However, bloom time in early spring, such as
now, is the second best of the year for control. Spring herbicide applications result in a
slightly lower rate of kill than fall applications, but they are still
worthwhile.
So,
for removing those dandelions, there’s a couple options, either hand pulling or
herbicide treatment. If removing the
dandelions by hand, you need to make sure to remove the whole root, rather than
simply hoe off the top growth. Any
portion of the root left in the ground can sprout at least one new plant. This mechanical removal is most easily done
if the ground is moist, so be sure to get out there soon after a rain for hand
pulling.
If there’s too many to hand pull, proper chemical treatment provides
effective control. A reminder that
glyphosate (Roundup) is a non-selective herbicide, so will also kill the grass
in your lawn. Instead, 2,4-D is the best
choice for dandelion control in lawns, as it only kills the broadleaf type
plants, such as dandelion, not the grass.
If you do choose chemical control for your dandelions, here are a few
guidelines
·
If there’s only a few weeds, simply spot
spray the herbicide. Apply just enough
to wet the leaf and do not apply to the point that the herbicide is dripping
off the leaf.
·
Apply the chemical to growing, preferably
young weeds. Don’t apply when the soil
moisture is low and weeds are drought-stressed, as the control won’t be as
effective.
·
Apply herbicides on a calm, clear day,
when temperatures are between 50 and 85 degrees F. Applying herbicides when the temperatures is
over 90 degrees increases the potential for volatilization injury to other plants
in the landscape.
·
Don’t apply if rainfall will occur
within 24 hours, and avoid applying irrigation to the area for at least 24
hours following an herbicide application as well. This is so the herbicide isn’t washed off the
plant’s foliage.
·
Don’t mow the lawn for 2 days before
or after the herbicide application. This
allows sufficient time for the herbicide to be translocated to the plant’s
roots.
As always, read and
follow the label directions. When making
liquid herbicide applications, keep children and pets off the lawn until the
product has dried or as specified by the label.
