Prohibited Noxious Weeds 
Agronomy 105's Weed ID
     Quackgrass
Quackgrass is an extremely troublesome weed especially in pastures and potato fields.  Like Canada thistle, it cannot withstand the extreme high temperatures of the southern United States.  Quackgrass is a perennial that can be a serious weed in home lawns and in row crops.
It can reproduce both by seed and by very extensive rhizomes which may be 20 feet or more in length.  These tough rhizomes are extremely troublesome in potato fields because they will grow right through a potato tuber thus destroying the marketable portion of the crop.
The seeds are borne in clusters on the inflorescence and often remain in these clusters until they germinate.  These seeds will be about 3/4 cm in length, straw-colored and somewhat flattened.  Quite often the seeds will be found with their awns still attached.  Quackgrass has been used in the northern part of Canada and in Alaska as a pasture species but is not the most productive forage species available.