- Understanding Weeds - How to
Kill them?
- by Chris Coffman
When I was a child, I loved to
pick Dandelions. The pretty yellow flowers were small, colorful,
and looked nice tucked behind my ear! However, if one had popped
up in the front yard, my hair accessory would have been considered
an atrocity!
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I often feel sorry for weeds.
They are plants too. In fact, if you flipped through a botany
field guide, you may be surprised at the plants you find classified
as weeds! But simply put, a weed is really defined as a plant
out of place. Clover in one persons flowing lawn may be considered
fashionable, whereas on another, not. Golf greens are often covered
with bentgrass, but if it crept up in some yards, it would be
considered a weed. While perhaps pretty on their own, weeds stick
out like a sore thumb in yards because they may be of a different
color, size or texture. This is distracting from the beauty of
the otherwise sprawling green turf. Aside from aesthetic values,
weeds can also drain nutrients from grass and other plants, and
this competition of resources can thin what should be lush. And
what's worse is that weeds are fighters. They can withstand conditions
that your wanted greens cannot, so they are almost inevitable!
Treating weeds begins with correct
identification. There are two classifications of weeds: Grassy
and Broadleaf. These are further broken down into groups like
perennial, biennial, and winter and summer annuals. These, as
you may gave guessed, depict their growing patterns. Grassy weeds
are, as they sound, like grass. However, they are unwanted grass,
or grass that is growing in a different type of lawn. Some examples
are annual bluegrass, barnyard grass, crabgrass, creeping bentgrass
and foxtail. Broadleaf weeds may appear more to be what most
people picture weed-like growth to be. Since they are broad,
they are more easily distinguished. Some examples are yarrow,
knotweed, chickweed, clover, ground ivy, thistle and my favorite,
the dandelion. |
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Once you understand what is growing
in your lawn and decide that it is unwanted, you can treat it
and/or control it. Weeds can actually be controlled by your lawn
care maintenance. If you maintain a dense and vigorously growing
lawn, you are already combating the problem. Weeds can be a sign
of underlying problems in the environment beneath. So by just
killing them, you are simply putting on a band-aid, not solving
the problem. For example, some weeds grow in situations of compacted
soil, such as knotweed. You can also control the growth by taking
better care of the grass, rather than focus on the weeds. You
can raise or lower the mowing height, change the frequency of
mowing and changing the amount of time between irrigating. Also,
you can increase or decrease application of fertilizer and aerify
the soil. This will maintain better grass, thus keeping the growth
dense and vigorous, which as discussed above, does not attract
weeds.
In addition to culture practices,
sometimes the assistance of chemicals is needed to control weed
growth. In that case, there are several types of herbicides that
can be used. Preemergence herbicides will affect seeds that are
germinating. Since they are best used two to three weeks before
the seeds start to grow, these work best to combat annual weeds.
Postmergence herbicides are used, as their prefix implies, after
the weeds have sprouted. Since they must be absorbed through
the leaves, this types of herbicide works best with a spray.
These can be used at any time, but are most effective when the
weed is still young and growing. Selective postmergence herbicides
are usually used to control annual, biennial and perennial broadleaf
weeds, as they will not damage grass. But, they can kill trees,
shrubs and flowers. These have to be used in proper conditions
as well, with no rain in the forecast for two days to follow,
air 60-80 degrees and no winds. Finally, non-selective postmergence
herbicides kill all types of weeds, and are best used to spot
treat grassy weeds that are not affected by the selective herbicides.
So next time you see a Dandelion
plant growing, don't make a wish and blow the seeds toward in
the direction of a lawn fanatic- they may not get the perfectly
manicured lawn they wished for! |
