Weed Facts

It has been said that an ounce of prevention is worth a pound of cure.  In regards to weed control, no truer words have been spoken.

Weeds in the central valley are mostly seasonal, and many of them can be prevented from sprouting altogether with the use of a pre-emergent.  Those that cannot be prevented should be dealt with quickly in order to prevent the development of seeds and other means of spreading, such as stolons and rhizomes.  When treated promptly weeds can begin to be controlled, and future outbreaks will become less severe over time.

During the spring and summer we see the emergence of many weeds, but the worst culprits are nutsedge, crabgrass, puncture vine, spurge, and purslane.

Nutsedge - While nutsedge may appear to be a grassy weed, it has a triangle shaped stem unlike grass plants.  Nutsedge can be difficult at time to control by mechanical means due to the fact that it grows a "nut" near the bottom of its root structure.  When a person attempts to pull the weed out, the nut often times is pulled off and remains in the soil and allows for future germinations.  Systemic post emergent weed killers, such as SedgeHammer ^TM, are the best way to get rid of this resilient foe.

Crabgrass - This number one nuisance of the central valley lawn can be prevented by using a pre-emergent once around March 1, followed by a second application 8 weeks later.  The key to proper timing is based on the weather pattern coming into the last two weeks of February.  Applications need to be applied just before the plants would start germinating when temperatures begin to reach 80 degrees.  However, should prevention not be possible, post emergent control is possible with the use of selective herbicides.

Puncture Vine - Named so for it's thorny fruit, puncture vine is one of the weeds that once established will make itself known by filling the soles of your shoes, or bicycle tires with thorns.  Like most weeds, this plant is much easier to control if a consistent prevention and maintenance program is underway before seed production begins.

Spurge & Purslane - These two prostrate growing weeds are extremely common during the heat of the summer months in the central valley.  While prevention is the goal, post emergent control will be necessary as these weeds tend to grow up through cracks in cement.

During the fall and winter we see the emergence of many weeds as well, some of which include annual bluegrass (poa annua), and fillaree.

Annual Bluegrass (Poa annua) - Commonly referred to simply as "Poa," annual bluegrass is one of the most invasive weeds we deal with.  By far the best means of control is to prevent it, but once any amount of annual bluegrass is introduced to a lawn it will spread quickly if action is not taken to remove it.  Annual bluegrass grows seeds extremely quickly and can grow them as low as one quarter of an inch high.  This means that mowing over these plants helps them spread quicker by distributing their seeds all over the yard.  Selective herbicides used consistently are the best means to control this tenacious weed.

Fillaree - Identified by beak-like structures, fillaree usually begins to appear during December when temperatures begin to stay below 60 degrees.  While this plant does not tolerate heat and typically will die out on it's own, fillaree can grow to substantial size if left unchecked.

Have a weed that you don't recognize?  Check out this weed identifier developed by the Illinois Council on Food and Agriculture Research.