AF
Why is my new Tall Fescue (ETF) lawn yellowing after 4 weeks?
I am 4 weeks post-seeding after a full Reno and generally really happy with how it is going but today I noticed some yellowing of the grass. Thought it might be fungal but it appears to be in areas that get most sun rather than the shaded areas of the lawn. Anything to worry about? If so, what should I do about it?
Just because it gets sun doesn’t mean it won’t develop disease. The close up leaf image is too blurry to clearly see what’s going on or determine whether a disease is present.
@KJ have added another photo of the yellow grass
Nothing here reads fungal to me. No mycelium in the canopy, no pink tint, no defined spots or lesions on the blade itself. Although the photos aren't great, you need to post close ups of the leaf blade where they're yellow, or check yourself for lesions. Google lesions of turf so you know what you're looking for.
I'd put this down to blunt mower blades tearing the blades, which you can see a bit of in that one photo. Mowing damp grass doesn't help either. It doesn't stand up straight for the blade to shear through, folds over and gets bunched and shredded instead of cut.
@Jonny Hicks Just seen your updated close up photo, still not much to go off to be honest. It is possible you have some very early leaf spot. I did a post on this a few days ago. Have a look at that and then go looking to see if you can find what I mentioned in that post. If you do, you might want to get an application of Azoxy down. To be honest, if it was me I'd be putting one down regardless. With these damp conditions it's a great preventative, and at the moment conditions are perfect for fungal activity. Until we have a couple frosts, that disease pressure isn't going anywhere.
What's your irrigation schedule like atm?
@Jonny Hicks thanks for the detailed comments. Just had the blades sharpened last week, so hopefully not that. We’ve had plenty rain recently, so haven’t irrigated apart from a brief burst to water in the remaining granular starter fert that I put down today. Maybe I need to drop the cut height a little more to help the grass dry out a bit? Will get some azoxy and put it down just in case it’s the start of something