Lawn surgery

Hot off the heels of the last application of Tenacity, since most of the creeping bentgrass is now dead (or at least appears to be dead) I didn't want to waste any time since this is the ideal time (for central Indiana) to plant grass seed. But before I did, I wanted to make sure that it's ok to plant so soon after spraying. I found an FAQ page with these questions and answers:

On which grasses has Tenacity been tested for use at or prior to seeding?
Tenacity is safe for use at or prior to seeding on Kentucky bluegrass, tall fescue, perennial ryegrass, and centipedegrass. Application at seeding can be made to fine fescue only if it is less than 20% of a seed mixture.

What are some of the unique benefits of Tenacity herbicide?
Tenacity has pre- and post-emergence activity on 46 dicot and monocot weed species. It can selectively control perennial monocots such as bentgrass and nimblewill and annuals such as crabgrass and goosegrass in many turfgrass species. Tenacity can be applied at the seeding to prevent weed germination and allow the turfgrass species to establish without weed competition.

I remember reading that, but I had to double check because it just seemed so counter-intuitive seeing as it turns mature Kentucky bluegrass tip white, so you'd think that young grass would be even weaker and more susceptible. Apparently not, which is fine by me!

I went ahead with planting some seed on Monday (9/2).

For this project I ended up using up a bunch of remaining stuff I had on the garage from previous years: some Scott's starter fertilizer, a bit of GreenView Grass Seed Accelerator (left over from this project), and hesitantly/fearfully the seed I used for last years reseeding. The other stuff should be fine, but the seed had a sell by date of 4/13 and of course is over a year old. I did a search online regarding the use of expired seed and the (completely unofficial) general consensus I gathered is that most of the seed should be fine as long as it was stored properly (e.g. not exposed to moisture), but to expect germination rates to be be lower (more so the older it is). As I often tend to do, I decided to take the risk, but put down more seed than I normally would to hopefully compensate. If 25% of the seed germinates, I'll be happy. We shall see.

Also "reused" in this project was the dead carcasses of the dead creeping bentgrass in lieu of straw or some other mulch, because I 1) didn't have enough of the Greenview Grass Seed Accelerator left, 2) didn't have any other mulch, and 3) was lazy and didn't feel like going to the store and buying any (I firmly believe that laziness is a prime fuel for creativity). In most places the bentgrass was pretty thick, so it just makes sense to me to use it, plus it made the project easier and cheaper - win, win... maybe?

So I used my manual tiller to loosen up the soil underneath the dead bentgrass and the pulled it back to reveal the soil below as seen in the following photos:

After this, I generously dispensed some seed into the soil using a handheld spreader, and then added some starter fertilizer also using the handheld spreader. Then I mixed it all up a bit into the top layer of the soil, covered it back up with the dead bentgrass clumps, and finally matted it down a bit by walking on a board I laid over top of each area. After which, the finished product looked like this (not much different than before!):

In some areas where there was more soil exposed, I put down
some of the GreenView Grass Seed Accelerator

In addition to the bentgrass areas, I also seeded some other areas that seemed to have died this summer (apparently I didn't irrigate enough!).

North side of the driveway (after tilling)

By the road (after tilling).

By the road (after seeding).

Closer shot of the previous.

As usual, I now anxiously await germination - which I hope does in fact happen! In the meantime I'll be irrigating to keep the soil moist.

I just can't seem to go a year without reseeding - maybe next year!

I'll report back upon germination, or lack thereof.

3rd (final?) Tenacity application

On Friday (8/30) I applied a 3rd application of Tenacity, that is 12 days after the second application and 29 days after the first. I didn't mix any more this time and instead just used what I had left in the sprayer which was about a half gallon. I decided to do a third application because 1) in some spots I still saw some sparse green bentgrass leaves (although most was brown), and 2) I missed a small patch in the first application (got it in the second, so it needed another). Hopefully that's enough to do the trick! It has seemed to work very well. Here are some photos from Sunday (9/1):

Dead patches that were once creeping bentgrass

The creeping bentgrass is looking quite dead! And the Kentucky bluegrass seems to be just fine and other than turning white a bit has not died.

Tenacity after 2 weeks + second application

Here are some photos I took on Thursday (8/15) which is 2 weeks after the first application:

More browned grass in there this time along with the white, but also still some green.

I applied a second application on Sunday (8/18).

Tenacity application after 1 week

This is the one week followup to the tenacity I applied to creeping bentgrass 1 week ago. The bentgrass is turning white and looks like porcupine fur, and the surrounding kentucky bluegrass is lightened in color as well. The instructions say that the surrounding grass may also turn white on the tips, but will eventually grow out of it.

Here are some photos of what it looked like yesterday (Thursday):

Tenacity applied

Having confirmed to a good enough confidence level, I ordered some Tenacity herbicide and applied it on Thursday (8/1). I couldn't find any dish soap to use as surficant that I was certain was non-ionic so I ended up purchasing some Bonide Turbo Spreader Sticker Concentrate online (not sure why they couldn't have just called it "Surficant", but anyway...).

Tenacity Herbicide & Bonide Turbo Streader Sticker Concentrate

This is what the label said for treating bentgrass:

Control of bentgrass (Agrostis spp.) and nimblewill (Muhlenbergia schreberi) - Apply Tenacity at 5 fl. oz. per acre in at least 30 gallons of water per acre at two to three week interval for up to three applications. Apply with a NIS surfactant. Bentgrass control may be more effective in the late summer/early fall just prior to onset of renewed bentgrass growth, than spring/early summer applications.

So I followed the label of both and mixed up 1 gallon of water with 1 tablespoon of the surficant and 1 teaspoon of the herbicide, and I applied just about all of it using a handheld sprayer. I also sprayed about a foot or so around the patches as I read somewhere that it'll help make sure to make sure to get all the stolons. I'm hoping to reseed these areas this fall, but if it takes 2-3 applications separated by 2-3 weeks that would mean seeding August 29th at the earliest (2x2 weeks) and October 3rd at the latest (3x3 weeks). We'll see how it goes.

Here are some before shots showing the creeping bentgrass in the lighter green (3 different angles of the same area):

It has spread impressively since last year when I first discovered it!

I'll try to post the progress. It should be interesting!

Creeping bentgrass... confirmed?

So I did some sleuthing and to the best of my grass identification skills (which admittedly are extremely poor), I believe I have successfully identified the front lawn turf invader to be creeping bentgrass. It has really grown quite a bit since a year ago and continues to spread. Something must be done. But before I get to that, here's how I went about identifying it.

I went off of my initial guess made last year as a starting point and searched for how to identify creeping bentgrass. This led me to this very useful and informative site from North Carolina State University's TurfFiles which has a profile page for creeping bentgrass describing it's various plant characteristics, including photos.

This led me out into the lawn with my macro lens to see if I could gets some photos of these key plant parts to help identify it and hopefully confirm or deny the identity by comparing with this site.
I was only able to get photos of some of parts as I didn't have much time. However, after inspecting the plant a bit and the photos compared with the TurfFiles photos it already looked like a match to me, but I'll get to that in a sec.

I also remembered a handy tool for identifying grass that I had tinkered with from Purdue University in the past. This tool helps to narrow down an identification based on some of the plant characteristics: vernation, ligule, auricles, leaf tip, leaf surface, mid-rib, collar, growth, and seedhead. I'm certainly still learning about these little plant details (never would have guessed that there'd be so many parts to grass), but I found the tufgrass identification guide linked from the tool to be a good introduction. Using this tool, I entered the characteristics that I was the most certain about (and by certain, I mean not at all certain):

1. Membranous ligule
2. Absent Auricles
3. Pointed leaf tip

At this point the tool had already filtered the possible contenders with a 100% match to just two: creeping bentgrass and colonial bentgrass. Additionally, I entered the leaf surface as ridged, but this didn't change anything as they both have that as well (and it turns out all but growth habit are the same between the two). Here are my photos that show these things:

A bit of a plant that I pulled

Shows the logn membranous ligule (the white
part) and the lack of auricles

After pulling back the blade

Rotated and even closer.

The blade tip pointed (the boat-shaped tip of a blade of kentucky bluegrass can
also be seen to the right)

So, the next step is to discern between colonial and creeping bentgrass. The nice thing about the tool is that you can view photographs of each of the parts for each specific type of grass, in addition to more specific information about it. It further states that colonial bentgrass has a short membranous ligule, while creeping bentgrass has a long ligule, with photos showing each. So even without knowing anything else other than these 3 or 4 attributes, the long ligule distinguishes the two.

But there's more. For colonial bentgrass it states:

"Technically possesses rhizomes and stolons they are generally absent and this species assumes a bunch-type growth habit."

 And creeping bentgrass:

"Bluish-green color, very fine leaf texture, tall membranous ligule, tolerates close 1/2 inch. Leaves may appear slightly rough along the edges, strongly stoloniferous."

So furthermore the two can be distinguished by their growth habits. One of the first things I noticed about the grass when I saw it was how it appeared to grow "horizontally" (likely via stolons, but I've yet to confirm this). It doesn't sound like colonial bentgrass would grow like this.

So there you have it: a positive identification... ?

Assuming so (and I feel confidently enough), the next step is to take action; and Tenacity herbicide sounds like the best available option. More to come.

Front lawn update

The front lawn is really doing great. I've very satisfied with it and feel great about all the work I've put into it over the last few years.

Here are some photos:

Today I transplanted some grass growing into of the garden beds to some small bare spots in the lawn.

My one last (for now) issue is the patches of mysterious evil grass #3 (#1 being orchardgrass, #2 being tall fescue). You can see them clearly in the following photos as the lighter green patches:

I don't have an ID on this grass yet, but one possibility is creeping bentgrass. I took some closer photos last year.

I was thinking that I'd just spray it with Roundup and replant this fall. However, I was doing some searching and if it is in fact creeping bentgrass, I found that there is a selective herbicide (active ingredient mesotrione) that supposedly will kill it without harming kentucky bluegrass (among other turf grasses)! One product based on it is called Tenacity which it seems people are having good results with for killing bentgrass. But it also kills a number of other weeds including crabgrass! It's rather expensive (about $75 for an 8 oz bottle of concentrate) as these chemicals seem to be, however, if that means I wouldn't need to do pre-emergent crabgrass prevention every year, it could be just as cost effective if not cheaper to go this route.

However, I'm getting ahead of myself. The first step is to ID it. This is not my forte, but I'll try my best. Here's some information I found on how to ID it. I'll report back.