Weed or Going to Seed?

Written by Matt Langemo

There’s a unicorn that runs around our office here at All-Terrain. Well, not a real, live unicorn, but a metaphorical one, and it is the yearly “grass going to seed” phone call.

Each year near the middle of May, Ryan comes into my office and says something to the effect of, “Matt, first off I want to let you know how intelligent and charming you are, and how lucky we are to have you at this company. Second, since the grass is about to go to seed, prepare yourself for a high volume of phone calls.” Why the high volume? When grass goes to seed it can resemble a weed. Then, low and behold (whatever that idiom means) I never get a single phone call. Each year I tell Ryan this, and he can’t seem to believe me. I don’t know if all those calls always only go to him, but I’ve never fielded a single phone call where somebody will complain about weeds, and it’s actually just their grass going to seed. I’m sure I’ve now jinxed myself and I’ll get a call from one of my friends thinking they’re witty.

However, to address those calls he gets, let’s talk about this whole “grass going to seed” thing. Well, actually I’ll do the talking and you can do the listening. Or rather, I’ll do the writing and you can do the reading. And ‘rithmatic.

Since Kentucky Bluegrass is the most common lawn grass in the Upper Midwest, this blog will focus on it. Many people know there are lots of different kinds of grasses that can make a lawn, but we’re all busy and I don’t have time to go into each one.

According to published work by North Dakota State University (GO BISON!), Kentucky Bluegrass (Latinized as Poa Pratensis) is one of the most abundant turf grasses in the United States. While bluegrass isn’t native to North America, we’ve taken it and made it our own (kind of like how we stole cricket to make baseball). It is identifiable by its “boat-shaped” leaf, or blade. It’s known as a “boat-shaped” leaf because the leaf is shaped like a boat. You’re welcome.

It’s one of the most popular grass varietals due to two major factors – that it tolerates cold weather really well and that it grows via rhizomes. “Rhizomes!” you say. Yup, rhizomes. Rhizomes visually resemble roots but play a much different role. Kentucky Bluegrass send their rhizomes through the soil parallel to the surface, and every so often will generate a “node,” from which sprouts up new grass. Many other grasses require seed to germinate new grass, but Kentucky Bluegrass can spread and thicken by either seed or their rhizomes.

Each year about this time, the soil starts to warm up to a point where Kentucky Bluegrass seed would germinate. Reports vary to exactly what the soil temperature needs to be to germinate seed, but 50-70 degrees is the window, with 60-65 seeming to be the most popular. Since seed would successfully germinate, Kentucky Bluegrass naturally produces it, thus the weedy appearance.

With proper germination conditions, germination takes 7-10 solar days. Once ground temps exceed 70-80 degrees, germination drops off significantly, if not completely. In our proverbial neck-of-the-woods, Kentucky Bluegrass only goes to seed once a year. So while your lawn may appear to be infested with weeds, you now know it isn’t. “And knowing is half the battle.” – G.I. Joe!