It’s the time of year when turfgrass rust begins to show up in Ohio lawns, particularly those that have perennial ryegrass. It occasionally shows up on Kentucky bluegrass and turf-type tall fescues.
We may see a little bit of this in the spring, but it really shows up in mid- to late summer and into the fall. Environmental conditions for this disease to thrive are perfect this time of the year.
Three are a few different types of rust fungi that are found in Ohio. These fungi are not harmful to humans or pets, but they definitely discolor whatever walks, runs or moves through the grass.
I was identifying trees for about two hours last week in the park and when I finished, the bottom of my legs looked like I had a bad experience with an orange bronzer. My shoes and legs were covered.
If you look closely at the turfgrass leaf blade, you can see the yellowish-orange powdery spores.
Environmental conditions conducive to turfgrass rust development include warm temperatures between 68-86F with prolonged leaf wetness (heavy night dews).
Turfgrass rust doesn’t usually kill turfgrass and good management practices can help to minimize the program.
It tends to infect plants that are stressed; therefore a healthy lawn is an important control tactic.
A good fertility program that provided nitrogen throughout the season helps to keep turfgrass vigorous. Mowing should be at the appropriate height (2½ to 3 inches).
Avoid soil compaction so that the roots can grow. Avoid moisture stress by irrigating if needed. However, don’t water in the evening, as this will keep the blades moist for an extended period of time.
If you don’t want to worry that much about your lawn with the above practices, just wait it out. Again, it’s not harmful nor will it kill the lawn, and eventually the environment will change and it will disappear.
If it really bothers you, contact a lawn care company, as there are fungicides that can be applied. However, it takes multiple applications.
A long-term strategy to reduce this disease in your lawn is to plant resistant cultivars. If you are starting a new lawn, you can select cultivars that have a high resistance to rust diseases.
You can also overseed a thin established lawn with resistant cultivars.
You can find information on cultivars that are resistant by visiting the National Turfgrass Evaulation Program website at: http://ntep.org/.
When you get to the site, you will have to do a little digging to find the results of the 2013 data collection. At the top you will find All NTEP Reports where you can select a species. Then click on Perennial Ryegrass, then click on the 2013 Data — Progress report under the 2010 National Perennial Ryegrass Test.
Go down to page 24 and you will find the results of the rust evaluations on perennial ryegrass. Those at the top of the list are the cultivars to look for in the garden center.
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