Why do we do any of this aeration and topdressing activity?
Mowing activities, maintenance vehicle traffic, cart traffic, walking traffic, rain, and more all have a compressing or compacting force on the soil, and aeration procedures are utilized to relieve this compaction and provide many additional benefits.
The benefits of aeration include:
- Creates space for new root growth.
- Improves oxygen movement into the soil, and plant and soil microbe by-product gas movement, out of the soil.
- Improves water movement into the soil, capturing rainfall and reducing run-off.
- Improves nutrient movement into the soil and provides ideal time to apply deficient nutrients or plant protectant products and/or other desirable soil amendments.
- Severs plant parts which in turn initiates new growth thereby improving plant density.
- Overall promotes a healthier, more drought tolerant turfgrass stand.
Conventional Coring and Reincorporation of sandy rootzone material on Tees
Solid Tine Aeration - (Sand was applied before aeration)
We employ both solid tine aeration, which removes no soil, (creating only an open channel in the soil), as well as conventional core aeration, where soil is extracted. Many times we will drag a flexible mat and/or a brush to pulverize these extracted cores and reincorporate the soil or sand that exists. In general we reincorporate cores on greens (unless we are using to propagate our nursery), and on tees, as the rootzone material on these areas is a desirable sandy material. On occasion after longer periods of time (years) we may remove cores completely if the organic matter percentage in the rootzone increases to undesirable levels.
Regarding the fairways, we core aerate and reincorporate (which acts as a soil topdressing) some fairways, and on others we apply sand topdressing then follow with solid tine aeration. The aeration helps incorporate the sand into the turf canopy.
Typical Conventional Core Aeration (last year-soon to begin this year). Cores will be pulverized and reincorporated into turf canopy.
Whether it's soil topdressing from reincorporated cores or sand topdressing, why do we care about topdressing?
The benefits of topdressing include:
- Smooths the surfaces, filling in minor depressions.
- Dilutes (with sand topdressing) and helps decompose (with soil topdressing from reincorporated cores) thatch material or the biomass of plant parts just beneath the turf surface
- Improves surface firmness and ball roll qualities (sand topdressing)
- Improves surface drainage over time as repeated applications build a modest layer (sand topdressing)
- May help reduce excessive earthworm populations (reducing annoying casts) - (sand topdressing)
- Reduces soil compaction which in turn helps root growth - (sand topdressing)
Fairway Topdressing in Action
Topdressed Approach #1 awaiting Solid Tine Aeration
I believe all of our fairways could benefit by sand topdressing (and we wouldn't have to play through wet muddy cores again should rainfall come unexpectedly, like could happen while we conventionally aerate many fairways -I'll explain more later) but we do have large fairway acreage which would requiring purchasing a lot of sand, a commitment to continue the program annually for several years, and labor and additional equipment investment. It certainly doesn't come without cost and other issues in the future. However, many clubs have sand topdressed their fairways for many years enjoying several benefits and there are some costs that are similar regardless of aeration method. Given our large fairway acreage and desire to evaluate the program before expanding to include all fairways, we selected a few (a third of the fairways) to begin sand topdressing and solid tine aeration. We solid tine aerate sand topdressed fairways as once we begin a sanding program we do not want to bring up soil cores and reincorporate them, as a layer of sand followed by a layer of soil creates layering that can be detrimental to water movement and lead to turf decline issues. So once we begin we will no longer "pull cores" and potentially be subjected to an unexpected rainfall and the mess that would follow, hence my reference to not having to play through muddy cores again.
We have several fairways that are in low lying areas (their surfaces are fairly close to the level of our main water reservoir, the channel between holes #3 and #11) and/or are some of the slowest to completely drain and dry following heavier rain events.These fairways are #3, #4, #8, #11, #13, and #14. The next few potential candidates could be #15 and #18, but we'll see how the program progresses on the first six mentioned.
Sand Topdressed Fairway (#11) showing Solid Tine Aeration nearly complete.
Brooming, Rolling (if needed) and Watering complete the process.
I'll keep you posted as to our daily work progress (which you can also see on the status board outside the ProShop) and on this blog in future posts, but I'm certainly happy to get your feedback as well, on whatever your experience is on these sand topdressed fairways. It will take a few years before we see full benefits but you may notice a little firmer feel and perhaps a little extra ball roll before too long.