Core Sampling at the Golf Course

What is core sampling in golf?

The core drilling is a soil aeration technique. A machine, called a core aerator, drives hollow tubes—known as “louchets”—into the turf, which extract small cylinders of soil, roots, and organic matter: the 'cores.” These are then collected, and sand is spread and brushed in to fill the holes. English speakers refer to'ventilation, core aeration or hollow tining.

The process mainly involves the greens, but also the tees and fairways. There are variations that do not involve removing soil, using solid tines that pierce the ground without removing any soil.

Why core the greens?

• Loosen the soil: The players' footsteps and the passage of mowers compact the soil, which then restricts the flow of air and water to the roots.
• Improve drainage: A green that drains well remains playable after rain and offers a more even surface.
• Limit the use of felt: This layer of dead organic matter accumulates under the turf. If it becomes too thick, it traps moisture, promotes disease, and makes the green soft.
• Promoting Roots: Air, water, and nutrients flow down more easily, and the roots follow.
• Improving Soil Composition: Over the years, the sand added to the holes makes the top layer more well-drained.

When do golf courses core?

Core aeration is done when the grass is actively growing, so that it heals quickly: most often in the spring and in late summer or fall. The schedule and frequency depend on the climate, the grass varieties, the condition of the soil, and how heavily the course is used. Clubs usually announce this in advance; if you book a tee time during these periods, check with the front desk.

After the operation, the greens remain marked with small holes and sand for a few weeks, until the grass covers the surface again—a process that takes more or less time depending on the weather.

Is it possible to get out of a drill hole?

Not automatically. According to the Rules of Golf, the divots are not on the course that requires repair, and they are not considered damage that can be repaired on the green. Unless the committee decides otherwise, the ball must therefore be played as it lies.

The committee may, however, adopt a local rule (Local Rule E-4), which grants relief without penalty when the ball rests in or touches an aeration hole:

• In the general area, the ball is dropped one club length from the nearest point of full relief;
• On the green, place the ball at the nearest point of full relief.

This local rule does not grant relief if the hole interferes only with the stance or, on the green, only with the line of the putt. Check the posted local rules before teeing off.

How do you putt on a green with divots?

• Hit harder Short putts: A ball that's too slow can be deflected by the holes and the sand.
• Expect a slower green and less consistent than usual, so adjust your speed control from the very first holes.
• Put things into perspective: On a cored green, everyone misses putts. That's the price we pay for having high-quality greens the rest of the year.