It’s easy to think of golf courses as swaths of uniform green grass; but in reality, healthy turf can be a mosaic of slightly different colors and textures for a variety of reasons. Most golf courses use different grass species and varieties for different parts of the course based on their suitability for a particular surface or environment. This often means that very different grasses are planted directly adjacent to one another – which inevitably leads to mixing of colors and textures when the grasses travel across their assigned boundaries. Even the population of a grass in its intended location can evolve and change in appearance and texture as new seed or genetic mutations become established. There are also uninvited guests in the form of broadleaf and grassy weeds that can find their way into golf course turf areas, altering the look and consistency of the course. Fully preventing this natural variation is impossible, and trying to control it too rigidly can quickly become an expensive proposition. Learning a little more about how and why golf courses develop differences in the appearance and smoothness of their grasses can help us understand variations we might see in different parts of the course throughout the year.

Putting greens are usually planted with one grass species, but that doesn’t mean they stay consistent for long. Bentgrass and Poa annua greens typically originate from seed, which means the individual plants are genetically different from one another. As a result, the development of differences in color, turf density and texture is common as these greens mature. Differences among the plants may become especially obvious during periods of drought, heat stress or cold weather, when certain areas go off-color more quickly than others. Most bermudagrass greens are established from genetically identical clones of the same plant but, over time, mutations or off-type characteristics can occur that create patches of grass with slightly different colors or textures. These variants can be most apparent during the winter months if certain patches hold their color longer than the rest of the green.

In fairways and roughs, different responses to sunlight versus shade, cool versus hot temperatures, different soil environments, fertilizer, water quality, irrigation practices, herbicides, fungicides, growth regulators, wear and heights of cut can have a big impact on the look and texture of the grass in different areas. Some grass varieties may perform well when mowed at certain heights, but can look and behave entirely differently when mowed higher or lower. Fluctuations in the weather will also have a bigger impact on large areas of the course that cannot be managed as intensively as the greens. A nice, dense stand of fairway or rough grass might look almost completely uniform during good conditions and then become mottled, tufted or thin during periods of suboptimal weather or heavy golf traffic. Fairways and roughs may also have more weeds compared to greens or tees due to the higher mowing heights and the cost of controlling weeds over such large areas.

There are various techniques superintendents can use to limit and manage the visual and textural differences across the turf areas on a golf course. Routine maintenance like mowing, topdressing and verticutting can limit potential impacts on playability, as can selective applications of plant protectants. Herbicide applications can be very effective when the unwanted plants are distinctly different from the desired species; but when it comes down to variants of the same or similar species, control can be very challenging or completely impossible. Superintendents must also be cautious about when they apply various products to avoid damaging the desired grasses.

With all the complexities involved in managing grasses over many acres, perhaps the best thing we can do as golfers is to be understanding of the inevitable variation and embrace the mosaic of colors and textures woven through the playing areas on most golf courses.