I'm currently battling a very similar weed after a complete lawn restoration in September 2013 so it looks like we could have the same problem. By the end of January it was completely weed free but I noticed these weeds popping up by mid February. The stuff I have is very easy to pull up after a rain when he soil is very moist and it doesn't appear to be spreading from the roots. I was thinking its crabgrass that germinated in the fall and sat dormant through the winter. Only problem with that theory is that we have had several heavy frosts and a couple snows which didn't kill them. I would have thought this would have killed crabgrass, right? The seed I used was the Hogan Tall Fescue blend from the Hogan company which clearly states on the label 0% weed and 0% other crop so I'm positive this weed didn't come from the seed. I did use straw I purchased from a local company so I'm thinking if this weed is orchard grass the straw is most likely where it came from. Some of these weeds in my lawn are just individual while there are others in small groups which to me indicates they were in the straw, some as complete seed heads while others were just individual seeds. Last weekend I put out an application of Prodiamine 65 WDG (Barricade) pre em in hopes it would keep more of this stuff from germinating but it doesn't say anything about controlling orchard grass. So far I have manually pulled about 50% of it but that's not much fun on 20,000 square feet of lawn with my beat up old knees! I did spot spray a week ago with Ortho Weed-B-Gon crabgrass killer which seems to be hurting it a little. Going to wait another week and do a second spot treatment and see what happens. Here's the photo of my weed for comparison: This post was edited by ForsheeMS on Sat, Mar 8, 14 at 9:42

Based on the shape of the flowers, I'm betting on Kyllinga vs. Nutsedge. Either way, it's not something you want in your turf. I've never Kyllinga myself, but I'm sure someone can give you advice on how to eradicate it.

crab grass, an annual weed grass. Your options are to 1) spot-spray it with Round-Up, although you will also kill surrounding grass with overspray, 2) hand-pull it 3) combo hand-pull/seedhead control this year and application of a pre-emergent NEXT year. If it were my yard I would hand-pull the crab grass and immediately treat bare spots with turf seed to fill back in.

First impression using the Chapman 20v is that it was really great. Performed as expected. Not too heavy when full. Straps seemed strong. It was comfortable on the back. Quiet. One disappointing thing that I experienced and that I have read somewhere else before is that the cap is really difficult to deal with. Cross threading with a bad seal is easy and even if you think you have a good seal nice and tight, well, product splashes and leaks from the top. You need to be VERY careful. I used blue dye and when I took the backpack off, the back of my shirt was wet with blue dye. Luckily the Prodiamine didn't make it through to my undershirt, but I rushed off to the shower regardless. Be careful of that cap!