Labor Day has come and gone and with it brought in the beginning of meteorological autumn. The end of summer brings cooler nights and perfect golfing weather, which incidentally is perfect turf growing weather. 

WARNING! The following post is rather long as I discuss the last two weeks.  To those of you that may not need to something to sleep to, I will sum it up in one paragraph:

Overall the course has recovered well from aeration and we are getting back on our regular maintenance schedule. Some of the greens had some issues with turf thinning, primarily in the areas with excess topdressing; which heated up burning the new leaves as they grew through the sand. The majority of the crowns were not damaged and are pushing through new growth so recovery should be pretty quick. I am confident that bar a few scars here and there they will be in great shape for the Rock - provided of course the weather cooperates.

For those of you that need some good material to put you to sleep and/or want to find out in detail what happened, read on!

5 green this morning; the burned turf is already recovering

I had been delaying the latest update until the course was fully healed from aeration to let everyone know how well it healed. The tees and fairways have healed up nicely. The verticutting on the fairways, and subsequent grooming, has them looking and playing beautifully. The topdressing on the tees has helped reduce the thatch on them but they will need more coring and topdressing to remove more. This will ensure the thatch does not build up to the point where it becomes an issue. Luckily this can be done during play without too much disruption and can be done anytime. We will schedule it at the end of season. 

 Looking back on 13 on 8-30; the greens were healing nicely and the tees and fairways were nearly 100%

The last thing left to do is to topdress approaches to keep them firm. A few are still a little wet and weak from the work so we are holding off until they are healthy enough to withstand the brooming. It will not affect play much and will be done in a few hours.

So to the big question: how are the greens? The simple answer is fine, but we have had some issues. As covered in the last few posts we had some issues completing aeration. On the Wednesday we were supposed to open back up, there was still some topdressing to be completed, which should have been easily completed in front of play. As with the earlier part of the week, we ran into problems with equipment which delayed us getting them done. The vertidrain started ripping up turf in areas, which needed to be repaired and the machine adjusted to stop it. This delayed the topdressing. As the morning progressed the temperatures rose and I had to stop topdressing to prevent damage to the turf. The damage occurs because the drag brush causes abrasion to the plants as it moves the sand; these abrasions weaken the plant and the heat exasperates it. So while the delay was not ideal, the turf appreciated it and there was no damage, but if you were one of the few that tried to play that day, please accept my apologies.

Some plugs on 1 green to repair the damage from the deep tine machine

A picture of the deep tine hole; showing the difference between it and the depth of the regular aeration channels which can be seen in the top few inches

A cross section of a regular aeration hole

After that hiccup the remainder of the topdressing went extremely well and the greens started to heal nicely. I waited until the following Tuesday afternoon to mow. With the course closed, it meant that there was plenty of time to make sure the first cut went well; the dry turf provided good conditions to mow and not pick up sand. I discussed in this earlier post the benefits of mowing when the turf is dry.

The greens looked good after the first few cuts, but the cut was a little scraggly. I then switched to the grooved rollers to get a better cut. However due to the length of the grass and the height the mower was set to, the grass was still not being cut as well as it should. It is difficult to explain the detailed reasons but a reel mower can only cut a certain amount of grass at a time based on it's speed, height of cut and number of blades. The height of cut was throwing that ratio out so I raised the mower a little closer to the height of the grass. It worked out perfectly, and the cut was beautiful. Everything looked on track for a speedy recovery. 

The cut on the right is after raising the height of cut by 0.025" - the mower was able to cut more efficently

The next day I noticed some browning on the greens. My initial reaction was the mower had scalped but it hadn't. In most of the spots, the sand was still visible and the color of the sand was causing the browning. Looking closer, the tips of the leaves were browning a little. It was nothing I hadn't seen before and I put it down to tip burn, probably from the fungicide/insecticide/fertilizer application earlier in the day. There were a number of new plants growing through the sand so the damage was just on the leaves. I was not concerned as the crowns were still pushing new growth, meaning the plants were still alive. Once they pushed through the sand, everything would look fine.

On Saturday everything was still fine; the plants were pushing through and the tips were a little browned. Turfgrass is like a finger nail. Basically the crown is like the cuticle and the point that the growth originates with the tip is the oldest part. This is the main difference between a grass plant and a tree as the new growth on a tree is at the tip.

8 tee shortly after it was aerated

When I came in on Labor Day, I was expecting to see these areas greened up, unfortunately the opposite was the case. The areas had completely browned out and the tips had burned back to the soil. There was no discernible pattern that would give an indication of a cause, nothing we had sprayed should have caused it; the weather - while not perfect - was not horrific. For one of the first times in my career I was stumped. The worst thing one can do at this point is do something in a panic as it could make things worst. It took me a while to clear my head of the shock and to start to dissect the problem to find the cause and the solution.

The biggest problem was that I was comfortable with my decision that it was fine on Friday and Saturday and now the turf was fading away while nothing had changed. Was the damage done or was there more to come? John, my assistant felt it was mechanical damage and I agreed that there was some as you could see lesions in the plant where it had been torn by the topdressing. I was not 100% convinced that that was the only factor. If it was all mechanical damage it would have been more widespread and be seen on more greens. 

Pouring over all our records for the prior two weeks didn't reveal a clearer picture. I went back out to pull some more plugs and see what was going on at the sites. The plugs revealed, that just like earlier in the weekend, the crowns were still green and alive and pushing new growth. But why were the leaves dying? The damage looked like scorched turf but we had been drying the turf out since the previous weeks rain, so it wasn't from too much moisture. The soils still had plenty of moisture and wilt and wet- wilt were both ruled out. 

Then I remembered back to a topdressing a few years ago where the kiln dried topdressing had not cooled down upon application and it burned the turf. The sand had been cooled when we applied it this time but could something else have caused it to heat up. As I started to work through the situation, I found the answer. 

Thinking back over the weather the previous few days, it had progressively been getting hotter with the humidity increasing. The turf on the greens had started to rot as it was too wet after the precipitation and due to the fact they were holding moisture, we had stopped watering them. While we were monitoring for wilt, we did not realize the areas where the topdressing was heavier and therefore exposed were heating up and did not have timely irrigation to cool them off. As a result, when the new leaves pushed though to the surface they were getting baked by the heated sand, killing them back. This is not something that one expects; while we were concentrating on reducing moisture levels to ensure the plants survived, they were actually cooking in the sand. Once I had my revelation, a clearer picture appeared. I now realized that the damage was on greens,or areas of greens, that for one reason or another had more sand on them and therefore slower to grow through. I also found the answer as to why the aeration holes were green in the browned out areas. In these areas, the turf was gone; the new turf had grown into them. The new growth was not buried and therefore not heating up.

Turf canopy temperature on an exposed topdressed area (after syringing)

Turf canopy temperature on a turf area (after syringing) beside the picture above

Once I realized what was happening, I immediately watered the greens and set up a program to water them overnight. The difference on Tuesday morning was startling. They looked quantifiably better.

On Tuesday I had a soil consultant out to rule out an issue in the soil, which we were able to do. He came up with the same answer that I did; i.e. the turf was being burned by the exposed topdressing. We also had a USGA Green Section agronomist out to offer his opinion and validate our course of action.

The upper picture is the top of the turf, when the sand is blown back (even just a little like here), the healthier crowns can be seen

The good news is now that we know fully what the issue is we can manage the recovery effectively. The better news is that there is a lot of healthy crowns beneath the sand that are pushing new growth. The healthy turf in the aeration holes is an advantage also. This means that they will look a lot better as soon as the new leaves pop through to the surface. There will be a few small areas that may need plugs or sod but overall they will recover pretty quickly. 

So what does this mean for aerations going forward? The deep tine aeration is essential to the future health of the greens. It might look like the extra topdressing that was needed to fill the deep tine holes added to the problems, but the timing of the topdressings is essential in the future. The equipment failures that caused the delays this year had a domino effect on the timing of when the greens were topdressed. The length it took to topdress was a lot longer than normal and the turf was growing all the way through. The turf was at different lengths when we topdressed affecting how the sand was worked in. Going forward, provided everything goes to plan, it will reduce these risks and we now learned to make sure we watch the heat of the sand on top of everything else.

Cross section showing the topdressing on the green and an aeration channel

Not to leave the remaining greens out, they have recovered beautifully, showing that we were on track to have everything recovered by the (now rescheduled) Club Championship. They would have been a little slow but fully healed over, which makes the thin greens even more frustrating.


 A member asked me why the fans were off and if had an effect on the greens that thinned out. The answer is a little contradictory but hopefully it makes sense. Due to the fact the greens had holes in them and were covered in sand our maintenance program had turned to a recovery program. As such the holes were providing big air channels for the roots so it was not as much of a concern. As the humidity rose and we looked to dry them out, normally we would start them up; however, the roots were severely compromised by aeration (this is temporary, caused by the stress, heat, additional fertilizer and in particular the excess water needed for a quick recovery. Once regular maintenance starts back, the aeration channels help increase root mass.) Due to the compromised roots we didn't want them drying out too quickly (as would occur with the fans) so it was easier manage them with the fans off. As you can see this job is a fine balance between contradicting items!

The last item that came up is one that always comes up at aeration time. I have discussed it in previous posts but will dedicate the next post exclusively to it. 

If you have any questions on the greens or the course, please do not hesitate to contact me as I am always glad to answer your questions. I can be reached via e-mail at alan@ledgerockgolf.com