Quackgrass is a perennial grassy Weed that is very difficult to eradicate from a lawn.  This persistent grassy weed can take over your lawn or invade open soil spaces rather quickly if left alone.  Quackgrass grows from seed and underground rhizomes (roots) that lie dormant overwinter but quickly revive each and every spring.  In the spring time (in particular) this problem weed grass usually grows faster and taller than other surrounding grass plants.  The reason this weed is so difficult to control is due to its resistance to selective herbicides that are routinely used in seasonal lawn care programs.  Even though we can quickly eliminate other unwanted grassy and grass-like weeds in lawns like crabgrass, barnyardgrass, foxtail, nutsedge, etc….. just not quackgrass – It lives on!  The best way to eliminate quackgrass is by applying a non-selective liquid herbicide like Round-Up (glyphosate) directly to the unwanted weed grass when it is actively growing (spring or fall).  Please keep in mind that this non-selective herbicide needed to eliminate quackgrass will also kill any/all desirable grass, plants, etc. that are allowed to come in contact with the herbicide.  It is a good idea to choose the right applicator (small paint brush, hand sprayer, back pack sprayer, etc.) that you can easily control to lessen the amount of excess turf damage.  If the quackgrass outbreak is very small in overall size than a paint brush (very tedious) or small hand sprayer (faster but expect grass damage as well) will do the trick.  However, if quackgrass has spread across your entire lawn than a larger back pack or tank sprayer should be utilized to make the application (please consult a professional for best results).  As you can imagine a lawn replacement/repair plan must be in place before making the decision to apply Round-Up to your quackgrass plagued lawn.  After waiting generally 14 days or so (post round-up application) you can repair the dead previously treated lawn areas by seed or sod to complete.