Once each year, the golf club engages a team of contractors to core our greens. Yesterday was the day. The process is something like this...
Step 1 - The coring machine runs over the green, extracting a 'core' of soil about 12mm diameter and 60mm long.
Step 2 - The cores are swept up and dumped somewhere nearby. They are used later to fill in low spots, cover bare places. etc.
The surface now look like this..
Step 3 - Another machine then comes along and spreads a fine sand across the green. This is a fairly critical step, as too much or too little sand can create problems later.
Step 4 - 'Verti-draining' is an additional step that involves another machine punching a spike about 30mm long into the green and vibrating the area to loosen the sub soil layer a bit.
Step 5 - Once the sand has dried out thoroughly, it is then 'swept' into the holes by dragging a metal mat around. By now, the grass is probably feeling a bit stressed, so we try to do this process as little as possible.
Step 6 - Finally, the greens are given well earned drink of water. Last night's 5mm thunderstorm was a big help too.
This morning, they look something like this...
Once the sand dries properly again today, a decision will be made whether to sweep them again or not. They'll be watered well for a day or so and any open holes will soon close up. They won't be cut for 4 or 5 days, and when they are, the height of cut will be adjusted to about 5mm, and on subsequent cuts be lowered gradually back down to the current height of 2.5mm.
Now we just have to 'nurse' them along for a bit. The soil should be well aerated, and should absorb water, fertilizers etc really well. Hopefully we can look forward to some nice greens to putt on throughout summer.