Identifying and Treating Winter Kill in Turf

Clint Waltz, UGA Extension Turf Specialist

Image - Winter kill in centipede taken from presentation by Clint Waltz, UGA Turfgrass Specialist
Image – Winter kill in centipede taken from presentation by Clint Waltz, UGA Turfgrass Specialist

We’ve received many questions regarding grass that has failed to green-up this spring.  With variations among four different warm-season species, multiple climatic conditions, and because of the wet conditions leading to a likelihood of disease, there is much to be said on the topic of “winter kill”.   In many incidents there are circumstances and extenuating factors that make a specific diagnosis difficult. If there were a year for winter kill, after the cold conditions this past winter and early spring, this would be the year for it.

Click here for a brief presentation about Winter Kill.

Dr. James McCurdy at Mississippi State has written a good blog on winter kill in his state, and over the past 30 to 45 days I’ve seen many of the same issues in Georgia so my comments would be consistent with his.

  • In many cases, bermudagrass has greened-up and is beginning to grow.  I’ve seen a few lawns and pictures of some bermudagrass that is still brown.  Patience may be the key with bermudagrass.  Soil temperatures have only been conducive for growth for about two weeks.  Remember bermudagrass has rhizomes, below ground stems, that were likely well insulated by soil.  Warmer temperatures and time will likely be suitable for bermudagrass recovery.  Check for extenuating factors like shade and ask questions about how long ice or snow remained on the lawn / grass.  I have seen some incidences where sledding occurred and the brown tracks are consistent with the path of wintertime fun.
  • Hybrid bermudagrass have recovered better than common-type (i.e. seeded) bermudagrasses.  The commons are recovering – all be it slowly.
  • Zoysiagrass have fared well but are slow to resume active growth.  See my comments for bermudagrass regarding soil temperatures and patience.  Remember, zoysiagrass is inherently a slow growing species, so recovery is going to take time.  It too has rhizomes and with time will regenerate itself as environmental conditions become favorable for growth.  To help, vertical mowing (i.e. verticutting) can aid in getting light and warmth to the soil surface.  This cultural practice can help remove dead leaf material and speed recovery.
  • Centipedegrass and St. Augustinegrass have suffered the greatest.  There are many cases where reestablishment is going to the best option.  Consider making the decision early (i.e. now) and getting started with sodding or seeding as soon as possible (see slides)
  • Grass that was sodded last year is a hit or miss. Some bermudagrass and zoysiagrass that is less than a year old seems to greening-up and doing fine. Some is not. This is more likely a result of post establishment care, position within the landscape, and how late into the summer or fall the grass was sodded. Grasses planted earlier in the summer seem to be doing better than those established later. That stands to reason as the earlier planted grass had more time to establish and produce rhizomes and roots before the onset of winter. However, I’ve seen some zoysiagrass sodded earlier in the summer, on a northern exposure that didn’t make it through the winter. Water wasn’t an issue most of 2013, third wettest year on record. As a result, the associated lack of ample sunshine during the 2013 growing season may have contributed to suboptimal establishment and production of carbohydrates – a biochemical molecule responsible for energy and energy storage. With compromised production of carbohydrates, the turfgrass plant had less stored energy to initiate growth (i.e. green-up) this spring.
  • Fortunately I have not seen many incidences where I think early spring fertilization is the primary culprit for “winter kill”. But I have spoken with a few homeowners and landscapers that applied nitrogen in late February and early March, before soil temperatures were conducive for warm-season root growth (65ᵒ F). One was a centipedegrass lawn where the early fertilization coupled with the “Easter freeze” likely affected the majority of the lawn. From what I’ve observed to this point, I think the early fertilization is more closely linked to increased occurrence of disease (e.g. large patch) which is making homeowners think their lawn was affected by the low temperatures. Regardless of year, this issue is self-imposed and 100% avoidable.
  • In my plots the three primary St. Augustinegrass cultivars grown in Georgia (i.e. Mercedes, Palmetto, and Raleigh) have had some degree of damage.  The difficulty with St. Augustinegrass is that in sod production it typically does not “lift” well during the spring, do it’s early summer before producers can provide a quality product.  If a homeowner is considering re-sodding St. Augustinegrass, they can start site prep now but be prepared that quality sod may not be available until mid-June.
  • Typically I don’t consider environmental injury as a primary culprit to turfgrass loss, but after last summer and this past winter it’s real this year, especially for centipedegrass.  I’ve seen several centipedegrass, and St. Augustinegrass lawns, that will likely need complete re-grassing.  There is little that can be done to recover these lawns in a timely manner and “sanding” will likely be of little help.  TifBlair does have improved cold hardiness relative to common centipedegrass but this year I’ve seen it injured too but that seems specific to areas that remained under ice or snow for several days.  TifBlair in more open areas where the sun shortened the duration of snow cover seems to be delayed but greening.
  • If reestablishment either from sod or by seed is desired – now is an appropriate time for either practice.  In fact, if seeding is chosen – the earlier the better.  If the lawn was healthy going into the fall, seeding may be the better option.  The homeowner can mow the existing lawn low (i.e. scalp), collect the biomass (i.e. clippings), opening the canopy for seeds to make soil-to-seed contact.  By keeping some of the existing grass it may help speed recovery and provides a medium for seed to become established (i.e. a nurse grass).  The caveat to this is there was no preemergence herbicide applied this winter or spring.  If so, then don’t seed.  The herbicide will kill the germinating centipedegrass seed too.  Lastly, follow watering and establishment practices for a newly planted lawn.

Demise of Small Mosquito Control Programs (and the Effect on West Nile Virus Transmission)

State public health officials in Georgia support an integrated approach for mosquito control. Local officials can contact the Department of Public Health for more information about how to conduct an integrated program in their counties.

Learn more at the Georgia Department of Public Health Web Page.

Also check out the Georgia Mosquito Control Association website.

Summary of an article by Dr. Rosmarie Kelly, Georgia Department of Public Health Read the entire article here

Asian tiger mosquito, Ary Farajollahi,
Asian tiger mosquito, Ary Farajollahi,

A number of published reports suggest that mosquito control programs, and especially those using Integrated Mosquito Management techniques, are needed to reduce the risk of arboviral (West Nile Virus and some other mosquito vectored diseases) transmission at the local level. A study from Michigan indicated that people in communities with no mosquito control program had a tenfold greater risk of West Nile fever/encephalitis than those in areas where mosquitoes were controlled

A Chicago area study suggested that mosquito control programs made a difference in WNV infection rates. The Des Plaines Valley District, with an intensive program to kill mosquito larvae, had four West Nile fever/encephalitis cases per 100,000 people, while the North Shore District, with a less ambitious program, had 51 cases per 100,000. This study showed that the program with the most mosquito surveillance and best documented larviciding and adulticiding operations had the fewest number of West Nile fever/encephalitis cases (Tedesco, Ruizand and McLafferty 2010).

This is not new information. The efficacy of aerial insecticide applications to reduce the transmission of Saint Louis Encephalitis (SLE) virus was shown during an epidemic in Dallas, TX in 1966. This study presented evidence that infection rate is reduced as a consequence of anti-mosquito measures. Before aerial spraying there was an SLE virus infection rate of 1 in 167 mosquitoes tested. After aerial control operations the SLE virus infection rate was 1 in 28,639 mosquitoes (Hopkins et al. 1975)

So, are small programs important? There was a documented increase in vector populations after the temporary closure of Clayton County, Georgia’s mosquito control program. There was an apparent increase in the risk of West Nile fever/encephalitis based on the presence of increased numbers of vector species and the detection of an early human case of West Nile fever/encephalitis in 2010. There was also a suspected increase in nuisance species and mosquito complaints, although these data were not collected. The Clayton County program has since been re-instated and is administered by Public Works.

Since the size of mosquito populations is crucial to disease transmission, it is important to reduce these populations below transmission thresholds. Even small programs can provide a reduction in vector populations and reduce the risk of vector-borne disease transmission.

Read the entire article here


Hopkins, CC et al. 1975. The epidemiology of St Louis encephalitis in Dallas, Texas in 1966. Am J Epidemiol 102: 1-15.

Tedesco C, Ruiz M, and McLafferty S. 2010. Mosquito politics: Local vector control policies and the spread of West Nile Virus in the Chicago region. Health & Place, 16 (6): 1188-1195.

Do you recognize this cockroach and know how to control it?

Do you recognize this cockroach and know how to control it?


The insect is a smokybrown cockroach. Read the following info to know how to identify and to control five types of cockroach found in Georgia!

This information is from the UGA publication, Management of Insect Pests in and Around the Home. The publication gives a full range of control options for 75 household pests based on pest biology. You will want to explore the entire publication, but this is an excerpt from the Cockroach Control section.

Cockroaches (Order Blattaria)

Cockroaches are large, night-active, fast-moving insects with a broad, flattened body, long antennae, and a relatively small head. The front pair of wings (called tegmina) are tough, protective, and lay on top of the membranous hind wings. Most cockroaches are poor fliers. None of the cockroach species listed below is indigenous to the U.S., but all are well established.

American cockroach (Blattidae: Periplaneta americana):

Adults are large (2 inches) with pale outer margins on the pronotum (upper thorax). Chestnut to light brown-colored insects that run quickly. Males and females are visually indistinguishable, although females are a little wider posteriorly than males.

American cockroach
American cockroach


Mainly found in sewers and other dark, damp hideaways such as basements. Rarely, if ever, found in attics. Night active. Sometimes found co-habiting outdoor harborage sites with smokybrown and/or Oriental cockroaches.


Apply gel baits (multiple small dabs no larger than a pea) or broadcast granular baits in areas where cockroaches are found. Bait stations can be used to control small nymphs, but adults and large nymphs may be too big to fit into the small openings in most bait stations.

Might Be Confused With:

Smokybrown cockroach, Oriental cockroach.

Smokybrown cockroach (Blattidae: Periplaneta fuliginosa):

Adults are large (1.5 inches) and uniformly dark cherry to dark red colored. Males and females are visually indistinguishable, although females are a little wider posteriorly than males. First instar nymphs approximately 1/8 to 3/16 inch, and identified by the white band across their back, just behind the thorax, and a white band on the tip of the antennae.

Smokybrown cockroach
Smokybrown cockroach


Most common cockroach in suburban, Southern neighborhoods with mature hardwood trees present, where they commonly live in treeholes, attics, crawlspaces, sheds and similar harborages with high humidity and protected from the desiccating effects of wind. Not commonly found in kitchens, as is the German cockroach. Night active. Sometimes found co-habiting outdoor harborage sites with American and/or Oriental cockroaches. Rarely, if ever, found in sewers. First instars not very mobile; their presence suggests nearby egg case hatch.

Smokybrown cockroach nymphs
Smokybrown cockroach nymphs


Apply gel baits (multiple small dabs no larger than a pea) or broadcast granular baits in areas where cockroaches are found. Bait stations can be used to control small nymphs, but adults and large nymphs may be too big to fit into the small openings in most bait stations.

Might Be Confused With:

American cockroach, Oriental cockroach.

Oriental cockroach (Blattidae: Blatta orientalis):

Adults are large (1 to 1.25 inches) and cherry to black colored. Males with short wings that do not completely cover the abdomen; females wingless (wingpads only).

Oriental cockroach
Oriental cockroach


Sometimes found cohabiting outdoor harborage sites with smokybrown and/or American cockroaches. Night active. Rarely found around homes in suburban environments. Biology and habits more similar to the American cockroach than the smokybrown cockroach.


Apply gel baits (multiple small dabs no larger than a pea) or broadcast granular baits in areas where cockroaches are found. Bait stations can be used to control small nymphs, but adults and large nymphs may be too big to fit into the small openings in most bait stations.

Might Be Confused With:

Smokybrown cockroach, American cockroach.

Asian cockroach (Blattellidae: Blattella asahinai):

Adults of both sexes about 1/2 to 5/8 inch, tan colored with dual, parallel stripes on back of pronotum (upper thorax). Males and females are visually indistinguishable.

Asian cockroach
Asian cockroach


Attracted to light, readily flies (rare for a cockroach), and found in shaded areas outdoors with leaf litter, mulch and/or high grass present. Rarely found indoors, unless attracted there by light. Flies during the day in response to disturbance (walking through habitat).


Alter lighting to make structure less attractive at night (see section in publication on Proactive Pest Management). Broadcast granular bait in areas where cockroaches are found. If desired, apply an appropriately labeled residual spray to those areas where cockroaches are found.

Might Be Confused With:

German cockroach.

German cockroach (Blattellidae: Blattella germanica):

Adults of both sexes about 1/2 to 5/8 inch, tan colored with dual, parallel stripes on back of pronotum (upper thorax). Males and females are visually indistinguishable.

German cockroach
German cockroach


Obligate indoor pest, never to rarely found outdoors except in cases of extreme indoor infestations. Found mainly in kitchens near and in warm appliances and sources of water. Night active. Under extreme levels of infestation this cockroach may be responsible for allergies, especially in children.


Use pheremone-based sticky traps to highlight areas of activity. Use gel baits and bait stations in areas (mainly in kitchen under the sink, next to the garbage, under/next to the refrigerator and stove, and in infested drawers) where German cockroaches are found. In moderate to heavy infestations, as many as 12-15 bait stations may be needed in a standard-sized home. Place bait stations on flat surfaces in corners and along edges of walls. When using gel baits, the application of many small bait ‘spots’ is preferred to the application of a few large bait spots (it does not take much bait to affect a large number of German cockroaches). If desired, in cases of extreme infestation apply a spot treatment with an appropriately labeled residual spray inside cracks and crevices where cockroaches are found. Total release aerosols (bug bombs) are ineffective at controlling German cockroaches, and should not be used indoors.

Might Be Confused With:

Asian cockroach.

About the Authors Daniel Suiter ( and Brian Forschler ( are Professors of Entomology, specializing in urban entomology, in the Department of Entomology at the University of Georgia; Suiter is located on the university’s campus in Griffin, while Forschler is on the main campus in Athens, GA. Lisa Ames ( directs the Homeowner Insect and Weed Diagnostics Laboratory on the UGA Griffin Campus. E. Richard Hoebeke, a systematic entomologist, is the associate curator of insects at the Georgia Museum of Natural History on the UGA’s main campus in Athens, GA (

This Memorial Day, We Salute the Military Entomologists

Adapted from an article in Entomology Today

Historically, more soldiers have died from insects than from bombs or bullets. In addition to malaria and yellow fever, soldiers have faced dengue, typhus, leishmaniasis and other insect-borne diseases.

The United States has taken the threat from insects very seriously. Today the U.S. Army, Navy, and Airforce all have trained entomologists to improve the health and sanitary conditions of their personnel. So on this Memorial Day — we thank our military entomologists, and all others who have served in the U.S. armed forces.

See entire article from Entomology Today.

Landscape Pop Quiz

Azalea lacebug Clemson University - USDA Cooperative Extension Slide SeriesThis is caused by Azalea Lace Bugs!

This information came from the publication Control of Common Pests of Landscape Plants 

Lace bugs get their name from the appearance of the area behind their head and wing covers. The area forms a lace like covering over the body of the insect. They are 1/8 to 1/4 inch in length and are partially transparent. Lace bug damage appears on the upper leaf surface as white to yellow chlorotic spots. The lower leaf surfaces will be cluttered with black spots and the old cast skins of immature lace bugs. Initiating control in the spring between March and May will reduce problems later in the season.

To find more id and control information on this or other landscape insects read the UGA publication Control of Common Pests of Landscape Plants 

To find pesticide recommendations and use information visit the Georgia Pest Management Handbook.

Warm and wet weather continues

Taken from the UGA CASE blog

Outlooks for the next two weeks indicate that our warmer and wetter than normal weather is likely to continue for the next couple of weeks.   The Climate Prediction Center is indicating that an area of particularly heavy rains may occur in far northeastern Georgia into South Carolina and western North Carolina on May 29-30.


In addition, some long-range forecast models indicate that a tropical depression has a chance of developing in the western Caribbean Sea early in June, with the potential to track over the Southeast if it does develop.  Of course, this is a long way away, but as we enter the Atlantic tropical season, the chances a tropical storm could form start to ramp up.  More on tropical weather on June 1, the start of the Atlantic hurricane season.  Meanwhile, major hurricane Amanda has formed in the eastern Pacific Ocean but is staying out to sea.  This is the earliest that a major hurricane has developed in this region in recorded history.

UGA Extension Celebrates 100 Year Anniversary!

Centennial video 1

100 Year Celebration Video

This special video highlights UGA Extension’s centennial with interviews from: former President Jimmy Carter; Georgia Governor Nathan Deal; UGA College of Agricultural and Environmental Sciences Dean Scott Angle; UGA Extension Director Beverly Sparks; and county agents Paul Pugliese and Kisha Faulk.

To learn more about the Centennial visit this site.

Heat Awareness Day opens the Memorial Day weekend

Taken from the CASE blog. See the original article here.

May 23 is Heat Awareness Day for the National Weather Service.  Memorial Day marks the unofficial start of summer for many people, and heat is one of the major killers of people and animals in summer months.  If you would like to learn more about the impacts of heat and how to prevent heat injury, click here.

Meanwhile, the next few days show the possibility of rain across most
of the Southeast with the exception of southern Alabama.  The rain should move into most of the area on Sunday afternoon (May 25) and continue into Tuesday (May 27) in the form of scattered showers and thundershowers.

UGA Extension launches climate blog for the Southeast

Merritt Melancon, news editor with the University of Georgia College of Agricultural and Environmental Sciences

Storm 1For the past two years, Georgia agricultural climatologist Pam Knox has kept Georgians up to date on the way the state’s climate impacts the state’s largest industry.

Starting in April, she started providing daily updates on climate and agriculture on her new blog “On the CASE (Climate and Agriculture in the Southeast)”.

The blog, which can be found at, features her monthly climate reports, climate and weather news from around the country, resources for farmers coping with extreme weather and crop updates.

She is also hoping to share the stories of producers around Georgia and the Southeast who are being impacted by remarkable weather or climatic conditions.

Please feel free to email her notes or photos about weather and climate across the Southeast impacting your farm or garden at

Don’t Forget to Mulch

Is it important to mulch around vegetables in a community garden?    After all,  plots aren’t very large, the plantings aren’t permanent,  and it can be a lot of trouble to bring in mulch.  The answer is YES!  It is important to go to the extra trouble and add mulch.  Mulching is simply adding a layer of material over the bare soil around your plants.  For an extensive review of garden mulches see Robert Westerfield’s circular Mulching Vegetables.

Mulching does several wonderful things for our warm-season vegetables.  It helps hold in soil moisture.  Think of those hot, dry, sunny, Georgia summer afternoons.  Bare soil gets baked; mulched soil does not. Mulch also helps even out the soil temperature.  This is helpful for root development.  Mulch can be a barrier to weed growth, reducing need for weeding. Also, mulch is a layer between the plant and the bare soil which can help prevent some rots that occur when vegetables or fruits lay on the ground.

A suggested mulching depth is 3 to 4 inches.  Too little mulch will provide limited weed control while too much will prevent air from reaching plant roots.  Keep in mind some mulches, like pine straw, tend to settle.  Compost mulches can be tilled back in the soil after the growing season.

Pine straw is a common mulch.


The best way to accomplish mulching in a community garden setting is to determine what materials are available and inexpensive.  Wood bark, compost, leaves, pine straw, and hay straw are all possible choices.

A bail of pine or hay straw will usually fit in a car trunk.  Wood bark and some composts come packaged in large bags which aren’t hard to transport.  Maybe the group of gardeners wants to have a larger amount of mulch delivered and split the cost. Oftentimes, municipalities will take old Christmas trees and recycle them as mulch as a service to the community.  These are usually free of charge.  Your county UGA Extension Agent will be able to answers any questions you have about mulch.

However you decide to get your mulch, you will be very glad you did come harvest time.

Happy Gardening!