Looks like quack grass. It could be orchard, barnyard or goose grass. Your description suggests Quack grass. It can be a very difficult grass to deal with. I have used Roundup to kill areas infested with quack. Some have tried painting the leaves with dilute roundup or using cotton glove over rubber glove to apply roundup to leaves. Bill Hill

doesn't quack grass get really tall? I mentioned this stuff NEVER gets tall, in areas where I don't mow it's still only 4-5" tall and has been there all winter as far as I know. When I pull it up there's no "nut" under ground, just fine runners.

I just found this description which makes me wonder if what I'm seeing could be tall fescue or perennial ryegrass? When I dig this stuff up I don't see thick roots (which I believe would be rhizomes), they're very fine and easy to dig up but it definitely sends out runners (are these runners what is called auricles?). In addition the fact what I have seems to never get very tall makes me think it isn't quackgrass.

Identifying Characteristics: A perennial grass weed with auricles that clasp the stem, rhizomes, and a long, narrow spike for a seedhead. The auricles of this weed helps to immediately distinguish it from most other grass weeds, however tall fescue (Festuca arundinacea), Annual Ryegrass (Lolium multiflorum), and perennial ryegrass (Lolium perenne) are similar grass weeds that also have auricles. However, none of these grass weeds have rhizomes like quackgrass.

Rhizomes are roots that spread horizontally to start new plants. I think they're what you're referring to when you say runners. Auricles are at the base of the leaves. Here is a page that discusses some of the terms used to discuss grass structures.

I'm not sure, but I think the grass in your picture may be Kentucky bluegrass (KBG).

I read a bit more and I believe what I'm seeing are stolons, not rhizones. I also read in more shady areas or if buried (I've seen it in areas I put bark as well in the lawn) that perennial ryegrass will send out stolons. I dug it up in a planter that has bark in it and noticed the stolons. I think the next step is for me to examine it more in the lawn itself and see if I find stolons.

The fact the stuff doesn't get tall even when left unmowed really makes me believe (thankfully) it isn't quackgrass. It's not an ugly grass, it's just a different color than the fescue which makes it noticeable.

By the way the grass seed I used is Pennington Kentucky-31.

Stolons are something like rhizomes, but they are above ground. If what you're seeing is below ground, they're rhizomes. I may be wrong, but I've always read that rye doesn't produce stolons or rhizomes.

I'm not a big fan of K 31, but it does have its good points. Its leaves are too wide for my taste and it tends to grow in clumps. I have some in my lawn and it stands out, but in a lawn of all K 31, it would probably look better. It does do really well at staying green in low water conditions, but because it doesn't spread, you'll need to overseed periodically.

What I'm seeing are I believe stolons as they run ontop of or right at ground level.

bpgreen: I'm beginning to think your comment above of it being Kentucky Blue Grass may be correct. Will kentucky blue grass tend to choke out fescue? If the two can coexist, especially if I overseed each spring with fescue seed I'm not too alarmed by the likely kentucky blue grass in my lawn.

The KBG probably won't choke out the fescue, but it will fill in bare spots. However, KBG spreads via rhizomes rather than stolons. Rhizomes should be below ground.

You may want to take some of the weedy grass (including some roots) to your extension service to your extension service to get an accurate ID. I've seen blades of grass from the same plant get identified as two different grasses from pictures. It can be very difficult to ID grass from pictures.

Many grass seed mixes have fescue and KBG in them. I think some types of fescue may mix better with KBG, but K31 grows much faster and has much wider blades, so I think a mixture of KBG and K31 fescue tends to look somewhat patchy.

Where in WA are you? You may be better off seeding in the fall. It may not matter as much if you're in the Seattle area, since it rains so often there, but if you're inland where it gets hot and dry in the summer, a fall seeding will give the grass more time to establish before the hot dry weather hits.

I'm in the Seattle/Tacoma area (between the two) where it is WET, WET, WET!! Plus I have a sprinkler system so no shortage of water.

I've been working to find out when the extension service hours are but so far they have been unresponsive, I'll keep trying...

The grass does look patchy, what I notice is the fescue is darker than whatever the other grass is (e.g., KBG). I was wondering if I overseed the lawn and hit the possibly KBG hard with fescue seed perhaps it will mellow out the difference.

I remember kidding a friend who came from Seattle and saying that there was a lot of rain. He told me that there's not a lot of rain, it just rains every day. I spent a couple of weeks there and understood exactly what he meant. I never opened my umbrella, but I don't think I saw a day without precipitation.

Since the KBG will spread if it's given a chance, you may have it in the lawn no matter how often you overseed unless you go on a mission to destroy it. If you overseed annually, you'll give the KBG less reason to spread, so maybe the fescue will dominate over time. I really don't know.

Anyone else have an opinion on bpgreen's comment of 'If you overseed annually, you'll give the KBG less reason to spread, so maybe the fescue will dominate over time. I really don't know.'?

Anyone else have a mix of fescue and kentucky blue grass in their lawn?