3/9/2021 - By Aaron Hathaway, Nufarm

Questions regarding naturalized areas or reduced input areas don’t only cover how to increase aesthetic quality or increase playability but how to accomplish these things with the fewest inputs as possible. This means thinking about the relative cost of inputs, the time it takes to provide an input, and which inputs are worth that time and money

Which Inputs are Most Important in Naturalized Areas?

Because these areas aren’t mowed regularly, weeds can get out of hand quickly. Herbicide applications are the most important input to maintain pure stands of whatever was established.

When perennial weeds with vast networks of vegetative reproductive parts, like common milkweed and Canada thistle, are left untreated they get stronger and multiply quickly. Turf managers should make time to treat these areas at least once per year; it won’t make a huge difference whether it is in the spring when weeds wake up or in the fall as they prepare for winter – consistency is key because weed pressure is constant.

Which Herbicides Will Be Most Valuable in Naturalized Areas?

Millennium Ultra® 2 is a broad-spectrum herbicide that consistently provides great broadleaf weed control on golf courses, including in naturalized areas. Some weeds emerge late, and some areas have high weed pressure and require some spot treatments midseason.

Sure Power® will burndown these weeds quickly and provides activity on a range of mid-season weeds including broadleaves, annual grasses, and many sedges. Those who have established these areas with fine fescues have a huge advantage when it comes to control of perennial grasses – sethoxydim and fluazifop can be applied over the top of fine fescue species to provide selective control of many perennial grassy weeds like quackgrass, reed canarygrass, etc.

Millennium Ultra® 2 “melts” tough weeds, even thistle, without leaving unsightly dead plants behind. Millennium Ultra 2 is also gentle on milkweed, allowing it to re-flower after initial suppression – ideal for monarch butterfly habitats.

Milkweed provides habitat for monarch butterflies, which makes Millennium Ultra 2 a natural fit for weed control in pollinator zones.

Sure Power, use late in the fall after you mow, in season in a back pack to thin areas, or as a rescue treatment when things have gotten out of control.

Just 7 days after a single application. Annual grasses like crabgrass, barnyard grass, fox tails, and sedges, and broadleaf weeds. Sure Power has activity on all those weeds to rescue a particular area that has gotten out of hand. Sure Power also kills these weeds quickly with one application.

How Can Established Naturalized Areas Be Thinned Out to Increase Playability?

Once these areas are established, they become much more difficult to thin out, so starting thin is key. These options for stand thinning should be tested as research in small areas as they are few and inconclusive. Keeping these areas thin will help increase plant aesthetics because they aren’t competing as much with each other, but thin stands increase the likelihood of weed infiltration, so, again, weed control is key.

1. Use PGRs. There is anecdotal evidence of superintendents using PGRs such as trinexapac-ethyl and prohexadione-Ca (Anuew™) to thin stands, but little conclusive research. PGRs are used in grass seed production fields to reduce lodging (plants falling over) and increase seed production, but not necessarily to thin turf stands.
2. Use preemergence herbicides. Because naturalized areas produce seed each and every year, a huge amount of seed is being added to the soil seed bank. If these seeds are allowed to germinate and recruit, they may increase density over time. A preemergence herbicide application may limit survival.
3. Nonselective herbicides like glyphosate or glufosinate (Cheetah® Pro) could possibly be used in creative ways to thin out naturalized areas. Perhaps a boom sprayer could be used with every other nozzle turned off and a random pattern through the areas. This may seem like an odd method, but it would get the job done quickly

For more information visit https://nufarm.com/usturf/naturalized-areas/ for videos, resources, and a chance to win Husqvarna Automower.