# Sand always on top after applied?



## dawk (Nov 29, 2021)

Why would you have to topdress every year once you topdress with sand? Why can't the organic material that builds up just stay on top of it? The sand was for levelling, not necessarily so that it was always on top.

See this Knorr comment

https://youtu.be/jBN6Up6jDeg?t=5m42s

So what are the issues? He doesn't say why. Drainage? Weird settling from uneven organic material decomposition?


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## ABC123 (Jul 14, 2017)

Personally I dont believe in sand topdressing and I would do what @Pete1313 did and core aerate like he describes in this post. https://thelawnforum.com/viewtopic.php?p=330455#p330455 If I had to add soil id find something as close to native as possible, root pruning over time will always add organic matter.

Organic matter can become hydrophobic and layers of organic matter could cause issues.

Page 10 http://kkarnok.com/pubs/LDSasCausedByHydrophobicSands.pdf


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## JML (Jul 26, 2021)

He's talking about layering. A lot of this can vary slightly depending on the type of soil you have. Essentially if you were to do a straight sand leveling job. Then do a layer of compost the next year, then sand the next year, you'd have these stacked levels of inconsistent material. In some areas (based on the soil type) can harden into a concrete type of material. Many people also think that adding soil will help with the leveling, but it's decomposition over time won't have the healing affect.

Again this has a lot to do with the type of sand you use and the soil you have/are adding. He goes on to talk about aerating and wanting to pickup the plugs. It's an option for normal users, strongly suggested if leveling, and mandatory if you have clay soil; since you obviously don't want puddles of clay on the surface.


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## dawk (Nov 29, 2021)

JML said:


> He's talking about layering. A lot of this can vary slightly depending on the type of soil you have. Essentially if you were to do a straight sand leveling job. Then do a layer of compost the next year, then sand the next year, you'd have these stacked levels of inconsistent material. In some areas (based on the soil type) can harden into a concrete type of material. Many people also think that adding soil will help with the leveling, but it's decomposition over time won't have the healing affect.
> 
> Again this has a lot to do with the type of sand you use and the soil you have/are adding. He goes on to talk about aerating and wanting to pickup the plugs. It's an option for normal users, strongly suggested if leveling, and mandatory if you have clay soil; since you obviously don't want puddles of clay on the surface.


What's bad about having layers of inconsistent material aside from possibly forming a concrete type material?

If you do get a layer of organic material, does scarifying or verticutting to kind of mix it into the bottom layer help mitigate the issue? He doesn't always bag his clippings so what does he do about it? Or is he saying he literally has to talk to this with sand every year now?


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## JML (Jul 26, 2021)

dawk said:


> What's bad about having layers of inconsistent material aside from possibly forming a concrete type material?


I would examine what your original goal was. You asked about leveling. Compost is not the best material for leveling a lawn due to its decomposition nature. If you're asking about a biological impact on the grass, it's almost none; assuming your native soil is similar to what you're adding.



dawk said:


> If you do get a layer of organic material, does scarifying or verticutting to kind of mix it into the bottom layer help mitigate the issue? He doesn't always bag his clippings so what does he do about it? Or is he saying he literally has to talk to this with sand every year now?


Scratching the top .5" is not the same as tilling in the material. Mulching clipping (when done properly) is extremely tiny pieces (Ryan mowes 3+ times a week) and decomposes very quickly to the point where it's nutrients entering the soil not bulk material.


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## The Anti-Rebel (Feb 16, 2019)

This article, though focused on golf, should be helpful on this topic.
https://www.usga.org/content/usga/home-page/course-care/green-section-record/58/9/dont-layer-it-on.html


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## xrn3p (Sep 16, 2020)

If a light layer of sand is spread evenly every year and just brushed in, without going heavy and raked in with leveling rake, will it help the lawn become just a little less bumpy over time?


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## bernstem (Jan 16, 2018)

The Anti-Rebel said:


> This article, though focused on golf, should be helpful on this topic.
> https://www.usga.org/content/usga/home-page/course-care/green-section-record/58/9/dont-layer-it-on.html


Keep in mind that most home lawns are not pure sand (much less a manufactured USGA sand based green) and the issues of layering and hydrophobicity that result from sand/organic layers are much less. Most of what follows below, therefore, does not really apply to home lawns.

In general, water does not move well from a fine layer (e.g. loam) to a coarse layer (e.g. sand). This is counter intuitive but is a result of water being held more tightly to the fine soil. What it means in practice is that a layer of fine organic matter over sand will prevent water from moving into the sand, but a layer of sand over silt will allow water to move into the silt. You can see how multiple layers of sand and organic matter can slow water infiltration and inhibit root growth.

For this reason, once you have established a thick layer of sand, you have to maintain the sand cap as sand and prevent layering. Core aeration with filling the aeration holes with sand will address the issue if the top layer is less than the depth of your aeration tines.

You may find this video useful.


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## dawk (Nov 29, 2021)

I don't see how _adding_ sand in fact ever is the problem. Adding _other_ things, no matter what you have underneath, seems to be the problem. Nor do the layers seem to matter. Having uniform clay is going to be worse than layers of clay alternated with layers of sand. It's just a question of what soil types might be in the way of water distribution. If you have clay, if you have non-distributed organic matter, it's going to reduce water distribution. Including if there is no sand below. Why would sand ever set things up to be *worse*?

Maybe in that it would promote horizontal water flow if there's something relatively non-absorbant below the sand layer.


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## dawk (Nov 29, 2021)

bernstem said:


> You may find this video useful.


That video was very good. This demo starting at 6:10 was fully convincing of the particle size and attraction principle you described.


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## JML (Jul 26, 2021)

xrn3p said:


> If a light layer of sand is spread evenly every year and just brushed in, without going heavy and raked in with leveling rake, will it help the lawn become just a little less bumpy over time?


The point is trying to add the sand to the low spots. Use a landscape rake, broom, drag, etc. to help pull those piles into the low spots. So if it's spread evenly and nothing is done, the bumps will all collectively remain the same. Brushing/dragging will pull the sand that's at the higher spots to the lower.


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