Chunking is a term that has worked its way into the language of golf architecture as more designers have embraced blowout bunkers, bunkers with native grasses around them, sandscapes, and just about anything with frilly edges. As an architect and shaper that spends a lot of time building bunkers, and loves sharing his craft, I wanted to take people behind the scenes of building golf’s natural looking sculptures.
Chunking is a construction technique for transplanting established grasses and plant varieties, along with the root structure, contained in about six inches of soil, directly onto a golf feature from the bucket of a machine. Chunking is normally done as a part of the shaping process, but can also follow with more of the grassing and finishing. The name comes from the amount of soil that gets scooped into the bucket of the machine with the plant material, normally an excavator. If done properly you can pick up and contain these decent size blocks of earth, held together by the roots of the plants and place them exactly where you want. Instead of a thin roll of sod placed by hand, the bucket slides the organic chunks, often with tall wispy grasses, straight onto the feature a few square feet at a time.
Chunks are great for building bunker edges. They can give a much more natural and matured look than sod, especially if you can find a nice mix of fine grasses and other plant life to harvest. In a northern climate for example, it is ideal if the hearty fescues have been on site long enough to have some blue stem, a variety of local sedges or even a few weeds mixed in. This adds different colours and textures. While some might be worried about the agronomics of not having pure stands of turf, chunking makes your bunker blend into nature faster. I can think of no greater compliment one can pay an architect or shaper than not knowing where their work started or ended. While chunking isn’t always the answer, I hate to see an old golf course that has just gone through a restoration look more modern than it did before!
From a construction perspective chunks also do a great job of limiting erosion during grow-in, and also need less hand work. What is really cool is that the teeth of an excavator bucket can cause all sorts of little tears and ragged edges as you dig them out of the ground: after placing the chunks along your new bunker edge you can go back in with hand tools – shovel, pick, or the back of a rake – pull the chunks apart, and accentuate the weathered look or give it more of a smooth clean edge to weather over time.
As an architect and shaper it is great to have a vision for what you want the landform or hazard you are building to look like. However, the thing I love about the chunking process, and the entire concept of design/shape as a whole, is that when you start to import and place chunks on the feature, often that vision changes and evolves during the process. As you work your way around the bunker, placing the chunks, sections will slide and break off. Sometimes you will see something your mind would have never come up with on its own and go with it. I really like to use the back and bottom of my excavator bucket to compact the chunks in place, as I move them around, and get them tight together. Sometimes this causes more things to crumble as you compact them: I don’t really worry about that. Some things aren’t meant to be and pieces will find a better more interesting and natural place to be! If you are comfortable with islands or little clumps of turf growing up and down the faces or floors of the bunkers they can add a lot to the naturally eroded look.
Chunking is not a new phenomenon that only occurs on new golf courses, nor was it invented by the architects and shapers of the minimalist movement, although they have certainly perfected it, and popularised the term. The implementation of excavators as a common machine and tool for building bunkers in recent times has been of crucial importance in helping to popularise chunking, but there are plenty of stories and evidence of it occurring at some of golf’s oldest and most famous courses. The famous ‘white faces of Merion’ were established and rebuilt with chunks by some of their famous superintendents long ago, just with different, less precise machines.
There are several chunking methods. I determine my process by how close chunking material is from the feature I am trying to build. If I am trying to build a feature directly into an existing landform already covered in the natural grasses I try to shape and chunk as I go: a shaping balancing act of sorts. With a bit of planning, or at least a good starting point, I will walk the machine straight into the area that will become the hazard, and start to dig, peeling away the vegetation, and exposing sand or the native soil cavity for the hazard. As I scratch away, I will generate material (soil and plant material), which I can use to add to the landform, or separate to haul away. In this scenario being able to balance the materials in chunks, and exposed sand is often ideal. The best shapers in the world are really good at this, and work their way around the natural grassy landform building up, digging down, and leaving a beautiful golf feature with little trace as to the machine that built it.
Another way of chunking, more common during renovations where material is more limited, involves a second person and machine to transport chunks around the site. I find a rubber track skid steer to be perfect for this. Often I will chop up the chunks with my excavator bucket and place them on the bunker in halves for easier handling and great details. With this method, depending on the course or project, sometimes you can rob chunks from already established native areas to to help establish bunker edges, and then set the natural areas back to seed. Sometimes you will run into a course or projects where there simply isn’t a really good amount of the type of plant life you are looking to chunk. However, with some forward thinking and planning, a nursery could be established well in advance to be used as needed during construction.
Jaeger Kovich is a golf architect, shaper, and founder of Proper Golf LLC
This article first appeared in issue 48 of Golf Course Architecture