Idaho lawns are susceptible to a wide array of weed problems including perennial broadleaf weeds like white clover and Canada thistle. As the name suggests, these weeds display wide leaves and are easily spotted within home lawns. Grassy weeds are more of a challenge as they look more like lawn grass but form patches or clumps within grass that ruins the uniformity of the home landscape. Grassy weeds that infest Idaho lawns are either perennial or annual plants like perennial smooth bromegrass and annual crabgrass, according to the University of Idaho Extension.
Even in lawns that are well maintained, problematic weeds can still infest your home landscape. When weeds grow in turfgrass, they compete with your lawn for required water and nutrients, sometimes blocking shorter grass from necessary sunlight. Particularly in cases of lawns that are already sparse or stressed, weeds can win the competition, take over and begin killing your grass when left uncontrolled. Weeds are virtually impossible to remove completely, according to the University of Idaho Extension, but consistent management can return your grass to a healthy state.
For the majority of weed infestation problems, the initial problem is a thin, weak lawn, according to the University of Idaho Extension. Like weeds, insects and diseases typically target weakened Idaho lawns, as well. Pests that feed on roots, such as white grubs, lead to plant death and are more likely to infest your lawn if weeds are present as the grass becomes even less vigorous and more vulnerable. The same is true with common lawn disease such as the fungal infection fairy ring that kills portions of grass. Likewise, weed-infested grasses become more susceptible to insects and disease. Control is essential in maintaining a healthy lawn.
For control, annual grassy weeds are managed with herbicides, but due to the need for specifically timed applications, contact a licensed professional for accurate treatment. Perennial grassy weeds are typically unaffected by herbicides; control through hand removal and the application of the herbicide glyphosate, if necessary. Glyphosate is a non-selective herbicide that kills all plant tissue it contacts, so extremely precise application is essential to protecting desired plants. For perennial broadleaf weeds, apply an herbicide with the active ingredient 2,4-D or dicamba, recommends the University of Idaho Extension.