Winter damage on bermudagrass – Turfgrass Science at Purdue University

Winter damage on bermudagrass

As bermudagrass begins to green up in southern IN and Kentucky , it is apparent that moderate to severe winter damage has occurred. Though we may be a little premature because full green-up and growth is still a week or two away depending on temperatures, it’s important to start formulating a strategy to repair the damage.

As a warm-season grass, bermudagrass can be sensitive to winter damage in spite of dramatic genetic improvement in cold tolerance. Though winterkill can be caused by a combination of factors, it is primarily dependent on moisture, low temperature and the duration of low temperature. The first three weeks in February were cold and dry, averaging almost 5-8 degrees below normal in Kentucky . With lows near zero, and almost no snow cover, some winterkill was expected. Low temperature can also be damaging when it occurs late in the winter or early spring and last a week to ten days like this year. This is somewhat analogous to cool-season grasses that can easily withstand high temperatures in May or June, but enter dormancy or die with those same high temperatures in August. Spring of 2007 was especially difficult because we had a week or more of record high temperatures in March where bermudagrass was starting to break dormancy, followed by a week or more of record low temperatures. Winter damage is compounded on wet or compacted soils, when overseeded with perennial ryegrass, when newly seeded/sprigged/sodded the previous summer, when growing on the edge of a southern or western shade, and/or when heavy traffic wears out the verdure (cover) to expose the soil surface. A survey of your golf course or athletic field will probably confirm this.

Now what? 
Bermudagrass is a couple more weeks away from typical expected full green-up as of writing this on May 16, 2007, so it’s likely that we’ll see some improvement by June 1. Also bermudagrass has tremendous recuperative capacity and anecdotally speaking, living plants on 6 to 8 inch centers may be enough to recover fully by July or August. If live bermudagrass accounts for 20% or more of any area, aggressive fertilization is the best plan.

Bermudagrass coverage of 20% or more: 
Aggressively fertilize at 1.0 lb N/1000 every two weeks starting as soon as possible. Weed control is critical to limit competition. Preemergence herbicides other than Ronstar (oxadiazon) will slow spread of bermudagrass by limiting “pegging down” of roots, so avoid the split application of preemergence herbicide if it has not been applied. In our work with seeded bermudagrass, MSMA for crabgrass and goosegrass has been the safest on new seedlings and we would expect the same on plants originating from stolons. MSMA also controls many broadleaf weeds. Carfentrazone (Quicksilver) is one of the safest broadleaf herbicides on seedling bermudagrass, but a number of other products including quinclorac, 2,4-D, and clopyralid are safe to use on seedling bermudagrass. If preemergence herbicide has not been applied, a shallow aerification followed by seeding bermudagrass at 0.5 lbs pure live seed (PLS) /1000 ft 2 will help improve cover. Purchased sprigs or sprigs harvested with a power rake from healthy areas can also be applied to thin or bare areas after a shallow tilling.

Bermudagrass coverage of less than 20% and preemergence herbicide has been applied: 
All preemergence herbicides except Ronstar can not be sprigged into for 3-5 months depending on the product. This is because these active ingredients are taken up by roots and will inhibit rooting of newly sprigged plants. Ronstar (oxadiazon) is taken up by shoots and thus it is safe to sprig when following Ronstar. If you have applied any of the other products and still need to resprig, wait until June 1 or June 15 when some of the herbicide has already dissipated, and then till the soil to 2-3 inches in order to dilute the remaining herbicide. Realize that this may only minimize the negative effects of preemergence herbicides. Tilling 10-15 lbs of activated charcoal per 1000 sq ft into the soil will improve germination but activating charcoal is difficult to handle. Following sprigging, employ aggressive fertilization, watering, and weed control like you would in any grow-in plan.

Bermudagrass coverage of less than 20% and preemergence herbicide has not been applied: 
Bermudagrass can be reestablished via sprigs or seed. Sprigging can be done as mentioned above or seeded varieties can be used. If seeding is chosen, soil preparation can be done with a light tilling or an aggressive aerification. Follow this with seeding at 0.5 pounds pure live seed/1000 ft 2 . The grow-in program includes 1.0 lb N/1000 ft 2 every 2 weeks, frequent irrigation to keep the surface moist but not saturated, and aggressive weed control as listed previously. A more complete report on seeded and sprigged bermudagrass can be found at the Purdue Turf Web Page at in “AY325: Bermudagrass for Athletic Fields in Southern Indiana and Southern Illinois”. For small winter kill areas, sodding may be the best choice. Though more expensive, sod is more satisfying for today’s impatient customers increasing playability (and revenue) faster than sprigging..

Rethinking bermudagrass? 
Bermudagrass is still the best grass for fall-use soccer and football fields in southern IN and Kentucky , especially if they are not used in spring. Spring-use fields are limited to the cool-season grasses Kentucky bluegrass, perennial ryegrass or turf type tall fescue, which are difficult to keep in playable condition throughout the summer, especially at the short mowing heights often required. Kentucky bluegrass has the advantage over tall fescue in that it spreads by rhizomes and recovers relatively quickly from damage. Perennial ryegrass establishes quickly and takes wear much better than other cool season grasses, but is susceptible to many diseases and will severely clump after heavy wear. Tall fescue requires 12 to 18 months to mature from seed before it can withstand traffic, so overseeding damaged tall fescue is problematic. A potential solution to this is sodding tall fescue, but avoid tall fescue that was grown with netting. The netting is not organic and will not deteriorate and may cause serious future problems with footing and tripping. The take home message is that even though bermudagrass will suffer winter damage sporadically, hot summers will damage cool-season grasses every year.

Zoysiagrass is probably the best grass for fairways and tees in southern IN and Kentucky , and it is far more tolerant to low winter temperatures than bermudagrass. However, we are seeing more winter damage with zoysia this spring than we have seen in the past 20 plus years. Its main disadvantages are Rhizoctonia large patch (zoysia patch) and slow establishment. Seeded zoysia is now available which decreases establishment costs over sodded zoysia. If you had devastating damage on bermudagrass fairways, conversion to zoysia is possible though you will likely continually fight encroachment from surviving bermudagrass. Two applications of glyphosate prior to reseeding will help limit the bermudagrass. A complete guide on establishing seeded zoysiagrass can be sent to you by contacting Jennifer Biehl at .

Share This Article
Disclaimer: Reference to products is not intended to be an endorsement to the exclusion of others which may have similar uses. Any person using products listed in these articles assumes full responsibility for their use in accordance with current directions of the manufacturer.
Turfgrass Science at Purdue University - Horticulture & Landscape Architecture, 625 Agriculture Mall, West Lafayette, IN 47907

© 2024 Purdue University | An equal access/equal opportunity university | Copyright Complaints | Maintained by Turfgrass Science at Purdue University

If you have trouble accessing this page because of a disability, please contact Turfgrass Science at Purdue University at | Accessibility Resources