It has been said, and is worth repeating, that naturalized rough areas are not necessarily low maintenance. The golfer’s idea of naturalized rough leans toward thin, wispy fields of fescue and little bluestem grasses scattered with a few wild flowers for interest and color. However, this does not occur naturally at most golf facilities unless they happen to be located on sandy, dry sites. Even courses with ideal growing conditions are faced with managing unwanted plants to keep naturalized roughs playable. Furthermore, transitioning from woodland or scrubland to naturalized rough presents an ever greater challenge.
Mowing Is Your Friend
The transition to naturalized rough can be hastened with a renovation program utilizing glyphosate. Using glyphosate may be the most effective approach for areas that need to be grubbed of tree stumps and rocks or where the existing grasses are not suitable for naturalization. Another option involves a slower process that encourages the growth of existing grasses while selectively controlling unwanted plants. In this case, mowing is your friend. Areas that are being transitioned into grasslands should be cut often in the first season or two. Frequent mowing will help “free” the underlying grasses while removing any unwanted broadleaf plants. Animals can also be used effectively to revitalize and help transition areas into grassland or meadow environments. Grazing goats and sheep may be an option for areas that are rocky or too severe to mow regularly. Goats are effective at browsing woody plants while sheep typically graze on grasses and forbes.
Herbicides are also an important tool when transitioning to naturalized rough. Herbicides containing 2,4-D, 2,4-DP, dicamba and triclopyr generally control most broadleaf and woody plants that may impede the transition to grassland. Herbicide applications can be made in the spring, but the best results are usually obtained with late-summer and early fall applications.
The Difficult Weeds
Deer-tongue grass and dewberry are common plants that are difficult to control in naturalized rough areas throughout New England. Dewberry is generally suppressed by broadleaf herbicides, but complete control is not easy and requires subsequent applications. Target dewberry in spring when the plants are blossoming or in late summer. Selective use of non-selective herbicides may be the best option against deer-tongue grass and other difficult-to-control plants. Multiple applications of glyphosate should ultimately control the plant.
Source: JimSkorulski (jskorulski@usga.org)
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