Nutsedge and Quackgrass
The picture is of nutsedge.
Nutsedge and quackgrass are similar.
They both appear to die in the fall, but they leave their seed and rysomes under the surface.
Every year they come back in greater numbers and the roots go sideways
sending new nutsedge, or quackgrass, shoots up through the soil.
Many weeds work this way.
These weeds are extremely tough for chemicals to deal with. They are quite resistant to herbacides.
And again, herbacides are not only poison to us, but harm the soil
making it easier for the surviving shoots to take over your lawn.
And again, the trick is to fertilize properly with the correct amount of a natural fertilizer.
Seed with a good quality grass seed when the weeds have gone dormant.
Now, even though spring or fall may be the only time these plants
are dormant, and reseeeding most successful, your soil is damaged and
it akes a while for it to heal. So start fertilizing organically now.