Annual Bluegrass Control in Turfgrass

Patrick McCullough, Extension Weed Specialist, University of Georgia

Annual bluegrass, Joseph M. DiTomaso, University of California - Davis, Bugwood.org
Annual bluegrass, Joseph M. DiTomaso, University of California – Davis, Bugwood.org

Annual bluegrass (Poa annua L.) is a problematic winter annual weed.  Compared to most turfgrasses, annual bluegrass has a lighter green color, coarser leaf texture, and produces unsightly seedheads.  Contrary to its name, both annual (live for one season) and perennial (live for many seasons) populations of annual bluegrass may be found in turf.  Perennial plants are more prevalent on closely mowed turf that receives frequent irrigation and high nitrogen fertilization.  These populations are more prevalent in shady or highly trafficked areas with compacted soil. Annual plants are more upright in growth and produce more seed than lower-growing perennial types.

Annual bluegrass seed germinates in late summer/early fall once soil temperatures fall below 70° F.  Seedlings grow and mature in fall, overwinter in a vegetative state, and produce seed in spring.  Annual bluegrass is a prolific seed producer and individual plants may produce hundreds of viable seed, even when closely mowed.  Annual bluegrass flowers over several months in spring and produces seed that may remain dormant in soil for years before germinating.  Annual bluegrass grows well under short day lengths and cool conditions, and may out-compete other turf species during late fall and early spring.  Annual bluegrass often dies from summer stresses but may survive if irrigated and pests are adequately controlled, especially for perennial biotypes.

Cultural Control

Several cultural practices can be utilized to control annual bluegrass.  Deep and infrequent irrigation encourages turfgrass root development which improves the ability of desired grasses to compete with annual bluegrass in mixed stands.  Withholding water until desirable turfgrass species exhibit initial drought stress symptoms can help reduce soil moisture for potential annual bluegrass infestations.  Overwatering, especially in shady areas, may predispose the site to annual bluegrass invasion.

Practices that promote soil compaction should be avoided to promote turfgrass growth and competition with annual bluegrass populations.  Core aerifications should be conducted during active turf growth and favorable periods for quick recovery.  Voids left in turf with exposed soil following aerifications may permit annual bluegrass invasion during periods of peak germination.  For cool-season grasses, fall aerfications should be timed before annual bluegrass germinates.  Warm-season grasses should have enough time to recover from summer aerifications to promote dense, high quality turf prior to annual bluegrass germination in fall.

Nitrogen fertilization should be reduced during peak annual bluegrass germination and periods of vigorous growth.  High nitrogen at these times encourages annual bluegrass spread and survival in to winter and spring.  Fertilizing dormant turfgrasses when annual bluegrass is actively growing may also exacerbate infestations and should be avoided.

Mowing height, frequency, and equipment requirements vary among turfgrass species and practitioners should maintain turf under appropriate regimes for successful long-term culture (Table 1).  Raising the mowing height during peak annual bluegrass germination may encourage turf competition to reduce potential infestations.  Lower mowing heights may predispose turf to stress and reduce competition with annual bluegrass populations.  Turfgrass should also be mowed frequently during periods of vigorous growth to prevent scalping.  Scalping thins out turf and may enable weeds, such as annual bluegrass, to establish. While returning clippings is recommended to recycle nutrients to the soil, removal of clippings may be useful when annual bluegrass is present and producing seedheads.  Removal of clippings at this time will reduce the spread of viable seed.

 Chemical Control

Preemergence Control 

Preemergence herbicides may prevent annual bluegrass seed germination.  However, preemergence herbicides will not eradicate established plants and will not effectively control perennial biotypes of annual bluegrass from spreading vegetatively.  Application timing of preemergence herbicides for annual bluegrass control is very important.  Herbicides must be applied in late summer/early fall before annual bluegrass germination.  A second application can be applied in winter to control later germinating plants.  Fall applied preemergence herbicides should not be used if reseeding or resodding is needed to repair areas of damaged turf within several months after herbicide applications.

Several preemergence herbicides used for summer annual weed control will effectively control annual bluegrass in fall and winter (Table 2).  Fall applications of herbicides such as bensulide (Betasan), dithiopyr (Dimension), flumioxazin (Sureguard), oxadiazon (Ronstar, Starfighter), pendimethalin (Pendulum, others), and prodiamine (Barricade, others) may effectively control annual bluegrass.  Indaziflam (Specticle) provides excellent preemergence control of annual bluegrass and also provides early-postemergence control as well.  Indaziflam is only labeled in warm-season turfgrasses but may provide greater application timing flexibility than dinitroaniline herbicides in fall.

Combination herbicide products are also available which may improve efficacy of applications.  These products include oxadiazon plus bensulide (Anderson’s Crab and Goose), oxadiazon plus prodiamine (Regalstar), and benefin plus oryzalin (Team 2G or Team Pro).  Many preemergence herbicides are available under a wide variety of trade names and formulations and turf mangers should carefully read label directions before applications.

Atrazine (Aatrex, Purge, others) and simazine (Princep, WynStar, others) are labeled for centipedegrass, zoysiagrass, St. Augustinegrass and bermudagrass.  Atrazine can be applied to actively growing and dormant centipedegrass or St. Augustinegrass but bermudagrass can be injured if treated while actively growing.  Both herbicides have excellent preemergence activity on annual bluegrass but soil residual is generally shorter (four to six weeks) compared to aforementioned herbicides.  Several atrazine products are restricted use pesticides and turf managers should check labels for further information before use.

Mesotrione (Tenacity) is labeled for use in centipedegrass, perennial ryegrass, St. Augustinegrass (sod production only), tall fescue, and dormant bermudagrass (Table 2).  Mesotrione may be applied during establishment of these grasses (except bermudagrass) and effectively controls annual broadleaf and grassy weeds.  Preemergence applications of mesotrione control or suppress annual bluegrass but postemergence use is ineffective for control of established plants.  Mesotrione may be applied in tank-mixtures with atrazine or simazine on centipedegrass to improve efficacy of applications.

Most preemergence herbicides will provide similar initial efficacy if applied before annual bluegrass germination and sufficient rain or irrigation is received.  Preemergence herbicides require incorporation from irrigation or rainfall so that weeds may absorb the applied material.  In order to effectively control annual bluegrass, preemergence herbicides must be concentrated in the soil seedbank.  Retention on leaf tissue can be avoided by irrigating turf immediately after application for effective soil incorporation and herbicide activation.

Preemergence herbicide applications on non-irrigated sites have less potential for residual control, compared to irrigated turf, from product loss, poor soil incorporation, and failure to activate the herbicide.  Practitioners should return clippings on non-irrigated sites to help move potential herbicides remaining on leaf tissue to the soil.  If clippings are collected as part of routine maintenance, practitioners should consider returning clippings until at least half to one inch of rainfall is received.  Granular products may also be applied to non-irrigated sites for better soil incorporation than liquid formulations.  Granular products may be easier to handle and apply with less equipment necessary than sprayable formulations.  Granular herbicides should be applied when morning dew is no longer present to avoid interference from leaf tissue.

Postemergence Control

Annual bluegrass may be selectively controlled with postemergence herbicides (Table 3).  Practitioners managing warm-season grasses have more options for selective postemergence annual bluegrass control than cool-season grasses.  Flazasulfuron (Katana), foramsulfuron (Revolver, Tribute Total), rimsulfuron (TranXit), and trifloxysufluron (Monument) are labeled for bermudagrass and zoyiagrass non-residential commercial lawns and other sites.  Flazasulfuron and rimsulfuron are also labeled for use in centipedegrass. Efficacy of these herbicides generally increases under warm temperatures in spring compared to winter and non-ionic surfactants may enhance efficacy.

Pronamide (Kerb) is a restricted use herbicide for annual bluegrass control in non-residential bermudagrass, centipedegrass, St. Augustinegrass, seashore paspalum, and zoysiagrass.  Pronamide is root-absorbed and must be watered in following applications.  Pronamide efficacy is generally slower than most sulfonylureas and activity for annual bluegrass control may take approximately four to six weeks.

Atrazine (Aatrex, Bonus S, others) and simazine (Princep, WynStar, others) may also be applied to bermudagrass, centipedegrass, St. Augustinegrass, and zoysiagrass for selective postemergence annual bluegrass control.  These herbicides often provide erratic control of annual bluegrass but may control other grassy and broadleaf weeds.  Actively-growing bermudagrass is sensitive to atrazine and applications are recommended only during the late fall and winter months.

Dormant bermudagrass may be treated with nonselective herbicides, such as glyphosate (Roundup, Touchdown, others), glufosinate (Finale), and diquat (Reward).  These herbicides will injure or kill existing vegetation, including annual bluegrass and managers should only spray at peak dormancy when no green turfgrass foliage is observable.  Nonselective herbicides should only be applied to completely dormant bermudagrass and applications during early spring may delay greenup with significant turf injury.  Flumioxazin (Sureguard) is a new herbicide for pre- and postemergence annual bluegrass control but applications are limited to dormant bermudagrass only.  Flumioxazin use after greenup or on other species are not recommended due to excessive injury potential.

 Selective annual bluegrass control options in cool-season lawns are limited.  Ethofumesate (Prograss) has controls established annual bluegrass in perennial ryegrass, tall fescue, and dormant bermudagrass (Table 5).  Two or three ethofumesate applications may be applied in late fall at three to four week intervals.  Annual bluegrass control may be seen that fall, but control is usually observed the following spring.  Annual bluegrass control with ethofumesate may vary greatly over years depending on environmental conditions.  Amicarbazone (Xonerate) is a new Photosystem II inhibitor, similar to triazine herbicides, but may be used in tall fescue lawns and other cool-season grasses.  Applications of amicarbazone in Georgia are limited to springtime only to minimize injury to cool-season grasses.  Warm-season turf is very tolerant to amicarbazone and may be treated at any seasonal timing.

Bispyribac-sodium (Velocity) has shown potential for selective annual bluegrass control in tall fescue and perennial ryegrass lawns.  However, this herbicide is currently registered for creeping bentgrass and perennial ryegrass on golf courses and sod farms only.  Spot treatments of nonselective herbicides are generally the most effective treatment regime for annual bluegrass control in cool-season grasses.

Managing Herbicide Resistance

Annual bluegrass is a genetically diverse species and various biotypes present in turf may have differential responses to herbicides.  Repeated use of one herbicide chemistry may effectively control annual bluegrass but resistance may develop in local populations if herbicides with different modes of action are not incorporated in to management regimes.  Herbicide resistance is the survival of a segment of the population of weeds following a herbicide dosage lethal to the normal population.  Resistance occurs from repeated use of the same herbicide or mode of action over years and may be a concern with problematic annual weeds, such as annual bluegrass.

Triazine herbicides, atrazine and simazine, have been repeatedly used for years due to the wide spectrum of weeds controlled as pre- or postemergence treatments in warm-season grasses.  Resistance in weed populations has been reported with these herbicides which may contribute to inconsistent efficacy for annual bluegrass control in turf.  Resistance to sulfonylureas has been reported in weed populations in agronomic crops and repeated use in turfgrasses may also contribute to resistance in annual bluegrass populations.

Preemergence chemistries, such as the dinitroanalines, may have resistance among weed populations from repeated use over years.  Turf managers should rotate preemergence herbicides from mitotic inhibitors to other modes of action to minimize resistance in annual bluegrass populations.  Herbicides to consider in rotation programs from dinitroanilines would include indaziflam, ethofumesate, or oxadiazon.  These chemistries offer a different mode of action than dinitroanilines but cost, label restrictions, and turfgrass tolerance may be limiting factors for using these products.  Combination herbicides are also available, such as oxadiazon + prodiamine (Regalstar), oxadiazon + bensulide (Anderson’s Crab and Goose), and prodiamine + sulfentrazone (Echelon), with more than one mode of action that effectively control annual bluegrass in turf.

Table 1.  Mowing requirements for commercial turfgrasses.

Mowing Requirements for Turfgrasses
SpeciesMower TypeHeight (inches)Frequency (days)
Bermudagrass
    CommonRotary/reel1 to 25 to 7
    HybridRotary/reel0.5 to 1.53 to 4
CentipedegrassRotary1 to 25 to 10
Perennial RyegrassRotary/reel0.5 to 23 to 7
St. AugustinegrassRotary2 to 35 to 7
Tall FescueRotary35 to 7
ZoysiagrassReel0.5 to 23 to 7

Table 2.  Efficacy of preemergence herbicides for annual bluegrass control in commercial turfgrasses.

Common NameTrade Name (Examples)Efficacy
atrazineAatrex, variousE
benefinBalan, othersE
bensulideBetasan, othersF
dithiopyrDimensionG
ethofumesatePrograssG-E
flumioxazinSureguardG
indaziflamSpecticleE
mesotrioneTenacityF
oryzalinSurflan, othersG
oxadiazonRonstar, othersG
pendimethalinPendulum, othersG
prodiamineBarricade, othersE
pronamideKerbE
simazinePrincep, othersE

E = Excellent (90 to 100%), G = Good (80 to 89%), F = Fair (70 to 79%), P = Poor (<70%).

Table 3.  Efficacy of postemergence herbicides for annual bluegrass control in turfgrass.

Common NameTrade Name (Examples)Efficacy
amicarbazoneXonerateF-G
atrazineAatrex, othersE
bispyribac-sodiumVelocityF-G
flazasulfuronKatanaG-E
flumioxazinSureguardF-G
foramsulfuronRevolverE
glufosinateFinaleE
glyphosateRoundup, othersE
imazaquinImageP-F
metribuzinSencorG
pronamideKerbE
rimsulfuronTranxitE
simazinePrincep, othersG-E
thiencarbazone + foramsulfuron + halosulfuronTribute TotalG-E
trifloxysulfuronMonumentE

E = Excellent (90 to 100%), G = Good (80 to 89%), F = Fair (70 to 79%), P = Poor (<70%).

What causes these irregular or circular patches in lawns?

Control Take-All Root Rot this Fall!

Alfredo Martinez, UGA Plant Pathologist and Willie Chance, UGA Center for Urban Agriculture

Take-all root rot -Clarissa Balibalian, Mississippi State Univ, Bugwood.org
Take-all root rot -Clarissa Balibalian, Mississippi State Univ, Bugwood.org

This year did your lawns show round or irregular dead or dying patches? Did the grass yellow or wilt even though the soil is moist? If so, these lawns may be infected with Take All root rot. This fungal disease affects cen­tipede, St. Augustine and Bermuda lawns

The fungus causing Take-All rots the lawn’s roots and aboveground runners (stolons).

To identify the disease look for:

  • Black, rotted roots.
  • Yellowed or dying areas of turf.
  • Stolons that are brown or black at the nodes or have dead patches.
  • One of the best ways to identify Take All is to look for the black, thread-like hyphae growing on the undersides of the stolons. You will need a micro­scope or a good hand lens to see these. Many UGA Extension County Offices have resources agents use to diag­nose diseases like this. Find your local UGA Extension office here.

This fungus prefers cooler weather – infecting lawns in the fall, growing through the winter and slowing growth in late spring. Much damage from this disease is done in the fall and spring. By the time we see disease symptoms (often in early spring and summer), the harm is done. Damage can be mistaken for green up problems. Expect the disease to be less active as temperatures increase.

Since this disease destroys roots, lawns may be slow to recover. Affected lawns are more susceptible to other stresses, like her­bicides and drought. Turf may not show evidence of the disease on the leaves until turf is stressed. For instance, a lawn with an unnoticed case of Take-All may be damaged or killed by the stress of a normal herbicide application. This can reflect poorly on the pesticide applicator.

Fall is the best time to control this disease. The best control is to improve cultural prac­tices to prevent the disease and to increase the vigor of the grass so that it will recover quickly. To slow disease progress:

  • Make sure the soil pH is not too high (Disease is less active below a pH of 6.5).
  • Water deeply and infrequently. Do not allow the soil to remain wet.
  • Remove thatch if the layer is thicker than one-half inch.
  • Mow at the proper height for your turfgrass.
  • Use fertilizers containing equal amounts of nitrogen and potassium.
  • Do not apply high amounts of nitrogen fertilizers in the fall. Typically warm season turf fertilization is completed by September 15.

Apply fungicides in September and again in October for best disease prevention. In warmer months, a fungicide may help, especially if sodding or plugging turf into affected areas. However, fall applications are best at controlling this disease. Fall applications should prevent the need for spring applications and should reduce Take-All damage in affected lawns and improve spring turf vigor.

For pesticide recommendations see the UGA publications –  Pest Management Handbook or Turfgrass Pest Control Recommendations for Professionals

For more information on controlling Take All see Turfgrass Diseases in Georgia or Enfermedades de los céspedes en Georgia

Stone Mountain Community Garden at VFW Park

Master Gardener Averil Bonsall and UGA Extension Agent Gary Pieffer show off a beautiful bed of watermelons.
Master Gardener Averil Bonsall and UGA Extension Agent Gary Pieffer show off a beautiful bed of watermelons.

The Stone Mountain Community Garden is a beautiful space located on an old ball field.  It is a partnership between the city of Stone Mountain and UGA Extension Master Gardeners.  When you first visit you will be impressed with the number of plots (50) and how well organized and maintained the raised bed plots are.  One master gardener site coordinator, Averil Bonsall, indicated that they have public demand for more but they are trying to keep it a manageable size.  You will also notice the wildlife!   A bee hive ensures that bees are present and they are busily flying around collecting nectar and pollinating the gardens which are full of vegetables, fruits and flowers.  Birds and pollinators are also attracted by the new meadow garden on the perimeter of the property and the sunflowers.

The garden has demonstration areas where gardeners can learn how to grow herbs and fruits.  A demonstration compost bin system is on the property and is used by the gardeners.  There is a 3,000 square foot pantry garden where everyone pitches in with the chores and the food is donated to the local food pantry in Stone Mountain.

To be part of the garden each grower pays a small annual fee and commits to provide two four-hour time periods of labor in the community areas of the garden.  This can be mowing the grass,working in the pantry garden, or weeding the demonstration areas.  As with all gardens, there is always a lot to be done.

Stone Mountain Community Garden
Stone Mountain Community Garden

The usual tomatoes, beans, and squash, are present as well as some unusual choices.  There is a large asparagus bed and a plot of dwarf okra.  Tomatoes are grown in hay bales here and there is an ornate trellis for growing pole beans.  The growers really do try new things and learn from each other.  For a brief walking tour of the garden visit A Walk Through the Stone Mountain Community Garden at VFW Park.

“The garden is a testament to the cultural richness and diversity of the nearby community.  Everyone works together and learns from each other.  They have put the ‘Community’ back into community gardening.”  – Gary Peiffer, DeKalb UGA Extension Agent

Happy Gardening!

Increasing landscape sales in the fall & winter


Does your landscape business slow down in the fall?  Look for services to sell to your customers and ways to more profitably use your time!
This could help you to maintain profitability in a slower time of the year, to build your client base and to prepare for next spring.

Fall and winter can be good times to . . .

  • Offer to conduct a sprinkler performance test.  Put a grid of cups across the lawn and run the system through one cycle. Is the amount of water in each cup about the same? If not, water distribution may be uneven which can lead to landscape issues. Look for leaks, controller problems, blocked or broken heads, misadjusted heads etc. Find the problems causing uneven distribution and fix them. Offering a sprinkler diagnostic service to your clients can help them to conserve water, improve landscape health and save money.
  • Re-set sprinkler systems so they run less often. Typically once a week should be plenty in the fall. Apply three-quarter to one inch of water every time you irrigate. Wait until the soil dries to water again. Once the winter rains begin, we can usually turn the systems off for the winter unless there are new plants in the landscape. In the colder areas of Georgia, you may need to drain the sprinkler system so it will not be damaged during a freeze this winter.
  • Offer a special on irrigation installation in the off-season.  
  • Plant or move woody trees, shrubs, and many perennials.  Late fall and winter is generally the best time to plant woody plants and many perennials. Planting in the cooler, wetter weather gives the roots time to get well established before they have to deal with our harsh, dry summer weather!
  • Soil sample to look for low pH or fertility problems.  This is especially important with St. Augustine, Bermuda and zoysia lawns but can be helpful in many situations. Your local UGA Extension Office can help with soil analysis.
  • Keep the leaves cleaned up from turf.  This will prevent matting during rains which can smother the grass. And it will prevent you having to explain to the homeowner why the lawn died in that area during the winter!
  • Offer a ‘clean up’ special for new clients needing help with fall leaves and clean-up. Use this as an opportunity to give them a free estimate for maintenance or weed control for the coming year. Perhaps you could offer them a discount for paying ahead for a full year of weed control.
  • Offer a special on installing hardscapes, outdoor living spaces or lighting or other services that you offer. See if you can move some of the ‘spring rush’ business to a slower time of the year.
  • Check trees and identify hazards that need to be dealt with. Trees are easier to evaluate for hazards when they have no leaves. Let a certified arborist handle tree issues since tree work is hazardous. Working on trees without the proper training and equipment can open your company to large safety and liability problems. Sub-contract tree work if you do not have fully trained, equipped and insured tree professionals on staff.
  • Conduct needed maintenance on your equipment. You may be surprised how much better a sharp mower blade cuts a lawn. Sharp blades produce a cleaner cut and a healthier lawn! Winterize equipment that you will not be using this winter.
  • Conduct inspections of established clients to evaluate the quality of your work, to get client feedback and to look for other services they may need. An online survey is a good evaluation tool as well, but get experienced help designing and interpreting a survey. And if you ask for client feedback, be prepared to make some changes!
  • Check mulched beds and add mulch if needed. Mulches to prevent weeds and conserve moisture should be 2 to 4 inches thick. Coarse textured mulches (pine bark and wood chips) are better used deeper (3 to 4 inches deep) while fine-textured mulches (pine straw and mini-bark nuggets) are better applied 2 to 3 inches deep. Do not pile mulch around the base of trees or shrubs since this can permanently damage the plant.

These are valuable services you can offer your clients and may be a way of helping you retain business and workers during a slower time of the year.

If you have ideas for increasing fall sales that you would like to share let us know!

Determining Planting Dates

Sometimes determining planting dates can be tricky.  We know that our fall vegetable garden should be in and growing when it is still hot, and dry, outside.  We also know that many cool season plants don’t grow well in the heat.  What to do?

Weather Station Map
Weather Station Map

The first step is to find out when the average first frost date is for your area.  Luckily in Georgia we have the Georgia Automated Environmental Monitoring Network (AEMN) which has weather stations all over the state.  These weather stations collect weather data year after year, including first frost dates.  This information can help us determine when to plant. Let’s say you live in Dallas, Georgia and you want to plant broccoli, specifically the cultivar Green Goliath.

If you visit the AEMN website, www.georgiaweather.net, and type in your zip code, 30132, you will be directed to the Dallas Georgia weather station.  Following the link for first frost date you will find years of data for your use.  Let’s just use the last six years of collected data:

2012    Nov 9

2011    Oct 30

2010    Nov 6

2009    Oct 19

2008    Nov 10

2007    Nov 7

Using this information we can determine when we want to make sure the broccoli has matured and hopefully been eaten and enjoyed.   These dates have a span of 22 days.  The earliest is October 19th and the latest is November 10th.  The October 19th date looks like it may be an outlier.  (A statistician could do better justice to this analysis I am sure!)  So, you may decide that Halloween, October 31st looks like a good date to work with.

According to The Southern Seed Exchange catalog, the information for Green Goliath says 55 days to maturity (DTM).  In this case the DTM is from the transplant stage.  So, if you are starting your seeds to create your own transplants you will need to add about 20 days to that number, 75 days.

Look at October 31st and count back in the calendar 75 days.  This leads us to August 17th as the date to plant your seeds. Experienced, and maybe obsessive, gardeners mark in their calendars key dates such as “100 days until average first frost date” and “75 days until average first frost date.”

If you live in Dallas Georgia today, September 17th, is 44 days until your estimated average first frost date.  If you are feeling lucky with the weather, you might find some Green Goliath transplants at your local plant store.

Happy Gardening!

Fall Management of Large Patch Disease in Turfgrass

Large patch disease - Alfredo Martinez, UGA
Large patch disease – Alfredo Martinez, UGA

Alfredo Martinez, Extension Plant Pathologist

Large patch disease of turfgrass is most common in the fall and in the spring as warm season grasses are entering or leaving dormancy. Large patch is caused by the fungus Rhizoctonia solani. It can affect zoysia grass, centipedegrass, St. Augustinegrass and occasionally bermudagrass.

Symptoms of this lawn disease include irregularly-shaped weak or dead patches that are from 2 feet to up to 10 feet in diameter. Inside the patch, you can easily see brown sunken areas. On the edge of the patch, a bright yellow to orange halo is frequently associated with recently affected leaves and crowns. The fungus attacks the leaf sheaths near the thatch layer of the turfgrass.

Large patch disease is favored by:

  • Thick thatch
  • Excess soil moisture and poor drainage
  • Too much shade which stresses turfgrass and increases moisture on turfgrass leaves and soil
  • Early spring and late fall fertilization.

If large patch was diagnosed earlier, fall is the time to control it with fungicides. Consult the Pest Management Handbook , Turfgrass Pest Control Recommendations for Professionals  or your local Extension Office for fungicide recommendations. Fall fungicide applications may make treating in the spring unnecessary. Always follow label instructions, recommendations, restrictions and proper handling when applying pesticides.

Cultural practices are very important in control. Without improving cultural practices, you may not achieve long term control.

  • Use low to moderate amounts of nitrogen, moderate amounts of phosphorous and moderate to high amounts of potash. Avoid applying nitrogen when the disease is active.
  • Avoid applying N fertilizer before May in Georgia. Early nitrogen applications (March-April) can encourage large patch.
  • Water timely and deeply (after midnight and before 10 AM). Avoid frequent light irrigation. Allow time during the day for the turf to dry before watering again.
  • Prune, thin or remove shrub and tree barriers that contribute to shade and poor air circulation. These can contribute to disease.
  • Reduce thatch if it is more than 1 inch thick.
  • Increase the height of cut.
  • Improve the soil drainage of the turf.
  • Apply lime if soil pH is acidic (i.e. less than 6.0 – except on centipede lawns). Soil pH of more than 6.5 can encourage take all infections.

See the current Georgia Pest Management Handbook for more information. Check fungicide labels for specific instructions, restrictions, special rates, recommendations and proper follow up and handling.

Additional resources:

Turfgrass Diseases in Georgia or Enfermedades de los céspedes en Georgia

Turfgrass Diseases: Quick Reference Guide or Enfermedades de Cespedes Guia de Referencia Rapida

UGA Pest Management Handbook

Turfgrass Pest Control Recommendations for Professionals

When is the best time of year to control fire ants?

Fall is the best time to control fire ants!

Original story by Sarah Lewis, student writer with the UGA College of Agricultural and Environmental Sciences

“April and September are good times to apply baits, once at the start of the season and toward the end to help control before they come back in the spring,” said Will Hudson, a professor with the UGA College of Agricultural and Environmental Sciences.

Fire ants are most active in warm weather. Fire ant season can last 10 to 11 months out of the year in the most southern areas of Georgia. Controlling ant colonies before they produce a mound is important. However, Hudson says that once a treatment program is in effect, timing is not all that important.

Baits and sprays

The general rule of thumb is if the area is one acre or less, don’t use baits. Re-infestation is more likely from colonies outside of the yard when baits are used.

One important thing to remember is the difference between ‘no mounds’ and ‘no ants.’ “There is a difference between eliminating ants and controlling them,” he said. “Baits do not eliminate ants because there is no residual control. A new colony can still come in and be unaffected by the bait laid down prior to their arrival.”

To eliminate mounds completely, apply baits every six months, Hudson said. “There will be invasion in the meantime, and you will still have fire ants, just not enough to create a new mound,” he said.

Hudson recommends treating lawns smaller than an acre with a registered insecticide in a liquid solution. This should rid the lawn of fire ants for one to three months. If you choose a granular product, measure carefully to be sure you apply the correct amount of material and get good, even coverage, he said.

The least effective treatment option for most people is individual mound treatments, according to Hudson. Treating mounds in general is going to be an exercise of frustration, and killing an entire colony by treating just the mound is a challenge, he said.

Minimal impact

Baits are considered to have minimal environmental effects for those who chose not to use hazardous chemicals. Once the bait is out, there is hardly anytime for anything to come in contact with it before the ants get to it.

Nonchemical options include using steam or boiling water. “We recommend using boiling water to treat a mound near an area such as a well where you do not want any chemicals,” Hudson said. “Using hot water is very effective, but the problem is you are not always able to boil the water right next to the area you want treated.” Carrying the boiling water can inflict serious burns, so extreme caution should be used when treating with this method.

There are products on the market that are approved by the Environmental Protection Agency and labeled as organic. Hudson says organic designation is a “slippery” definition. There is an official USDA certification and many states have their own set of regulations when labeling a product as organic. This labeling can mean the product is either a natural product or derived from a natural product. “While there are a few products that qualify as organic, with most baits the actual amount of pesticide applied is minimal,” he said.

Realistic expectations

Hudson says to be careful when choosing a product because the labels can be confusing, even deceptive, and it is difficult to make the right choice. For assistance in selecting a product, contact your local UGA Cooperative Extension agent.

“The most important thing to remember is that you need to be realistic in your expectations,” Hudson said. “If you are treating mounds, you need to be prepared. You are going to chase the mounds around the yard.”

For more information on selecting a control measure:

Find pesticide recommendations in the UGA Pest Management Handbook

Fire Ant Control Materials

Managing Imported Fire Ants in Urban Areas

Fall is the best time to treat for fire ants

 

Honey Bees in the Community Garden-A Guest Post by Jennifer Grimes

The Georgia Tech Urban Bee Project
The Georgia Tech Urban Bee Project

As people become increasingly aware of the importance of pollinators, more community gardens are considering establishing a honey bee hive (or three) of their own. Not only do bee-flower interactions increase garden productivity, bee hives can provide great educational opportunities for the communities that keep them.

By providing pollinator support to your garden, you are greatly increasing the chance that your crop yield will be heavier and of better quality than without bees. To give just one example of this, the Honey Bee Project of the University of Hawaii found that the addition of one hive to a hectare of cucumber plants can result in three times the fruit production as compared to a plot with no hives. Moreover, in terms of fruit development, they found that a minimum of eight to ten bee-flower interactions is necessary to produce a cucumber of adequate quality.

Bees provide crucial agricultural support to gardens, but they also afford us with important learning opportunities in regard to the ecology and interconnected nature of our food systems. The practice of keeping bees permits communities to learn about the living systems that provide food for us. Around one third of our global food production and 90 percent of wild plants are dependent on pollinator services. As bee populations decline due to Colony Collapse Disorder, rampant pesticide use, loss of habitat, pests and diseases, and genetic uniformity caused by selective breeding, the spreading of awareness is increasingly critical in our efforts to reverse the problem. The bees give us an opportunity to increase awareness of how to not only live sustainably within the system, but how to nurture it as well.

Now that we know how the establishment of bee hives in our community gardens can help us as gardeners, we need to ask ourselves how we can help the bees. Beekeeping is a fun, rewarding hobby, but taking upon the responsibility of caring for a colony of bees not a task to be taken lightly. Establishing beehives in your community garden requires either procuring a local beekeeper or becoming a beekeeper yourself in order to maintain the hives. Beekeeping associations often offer beekeeping courses in the early spring. Though these are not required to become a hobby beekeeper in Georgia, they are highly recommended for the benefit of the bees and the keepers.

Honey Bees Coming Home - photo by Jeff Martin
Honey Bees Coming Home – photo by Jeff Martin

In order to ensure a healthy, happy hive, take part in best management and good neighbor practices. It’s critical that your hive has a variety of non-pesticide-laced wildflowers to forage for food when crops are not in bloom. Strategically planting varieties of native wildflowers that bloom when crops are not blooming will provide season-long food supplies to keep your honey bees, as well as our critical native pollinators, healthy and productive. Plus they are pretty!  It is also important that the bees have access to a clean nearby source of water; they need this to help produce food for baby bees as well as to cool their hives during the hot summer months. Keeping these necessities close by will discourage bees from traveling long distances and wasting energy that could be used to make honey, as well as from becoming a nuisance by spending too much time around your neighbor’s pool.

In regard to liability issues, there’s no guarantee a neighbor or visitor won’t bring a nuisance or negligence case against you regardless of the precautions you’ve taken. As Georgia has no laws protecting beekeepers from these legal actions, this topic is open for legal interpretation. However, the liability risk is negligible in comparison to the great ecological benefits that these insects provide. Moreover, honey bees are an extremely docile species of bee and the likelihood of being stung is extremely low, especially when they are not in their hive. Unfortunately, many people mistakenly believe they have been stung by a honey bee when in fact they were stung by a yellow jacket or other aggressive stinging insect. Considering that the act of stinging causes the bee to die, this action is only taken as a last resort when defending their colony. Some beekeepers claim that honey bees are so docile that, when foraging for food in flowers, they can even be pet.  Keith Delaplane, a UGA entomologist has a thorough publication, Honey Bees and Beekeeping.  Helpful information on all types of bees can also be found through the Xerces Society.

If you’re interested in establishing a bee hive in your community garden, you can learn more by visiting local beekeepers, taking some beekeeping classes, or by contacting your local UGA Extension office.

Jennifer Grimes is a City and Regional Planning Graduate Student at Georgia Tech. She is currently an intern with the Georgia Tech Urban Honey Bee Project. Jennifer is also a home brewer and plans on making mead in the near future using local honey – Honey Bee-r!

Happy beekeeping!

 

 

 

Tawny Crazy Ant found in three new locations

TAWNY CRAZY ANT

Daniel R. Suiter, Department of Entomology, University of Georgia, Griffin, GA

Tawny crazy ant worker. Photo by Danny McDonald. Click on the image to view the major identifying characteristics. Image from Texas A&M publication found at http://urbanentomology.tamu.edu/ants/rasberry.html
Tawny crazy ant worker. Photo by Danny McDonald. Click on the image to view the major identifying characteristics. Image from Texas A&M publication found at http://urbanentomology.tamu.edu/ants/rasberry.html

Discovery.

In August 2013 James Morgan (UGA Extension Agent in Albany, GA) was the first to find the tawny crazy ant, Nylanderia fulva, in Georgia. Read the story here. Until Morgan’s find, the tawny crazy ant was known from sporadic counties in Mississippi and Louisiana, but was widely-distributed in Texas and Florida.

The tawny crazy ant was formerly known as:

  • The Rasberry crazy ant (after a pest control operator, Mr. Tom Rasberry, the discoverer of N fulva in Texas)
  • The hairy crazy ant (under a microscope the ant appears hairy) and
  • The Caribbean crazy ant (given its FL distribution)

The tawny crazy ant is an invasive ant species from South America with widespread distribution in Texas and Florida. The tawny crazy ant’s biology and general, visual appearance, to the untrained eye, is similar to that of another South American invasive ant species common in Georgia, the Argentine ant (Linepithema humile) (known to Georgians as “sugar ants”). While the tawny crazy ant was detected in Georgia in 2013, the Argentine ant has been established in Georgia for more than 100 years. Neither are native to Georgia.

Trends.

In August 2014 three additional tawny crazy ant sites were brought to our attention by Jarrell Jarret, Arrow Exterminators in Brunswick, GA in conjunction with Don Gardner, UGA Extension Agent. Two sites were found at I-95, exit 26 (Waverly, GA). Neither site was more than a quarter mile from the interstate (one east and one west of I-95). Both sites are in Camden county.

We suspect ants were transported from Florida. A fourth site was found just 3 miles north on I-95, at a gas station (exit 29). This site is in Glynn county.

We suggest that UGA Extension Agents and Pest Control Operators on Georgia’s coast, in southeast Georgia, and in the southern half of Georgia should be on alert for the existence of this major nuisance ant pest. In areas of Texas where the tawny crazy ant has appeared, it has become a tremendous nuisance. Although unseen, and perhaps less appreciated by homeowners, invasive species, including ants, can be highly disruptive to native habitats. Invasive ants commonly drive native ant species to extinction, and can disrupt the “balance” of native ecosystems, resulting in a cascade of detrimental impacts on a system’s ecology.

Control.

Control of the tawny crazy ant is similar to control of the Argentine ant, and includes (primarily) the direct application (strictly by label) of fipronil, pyrethroids, or other labeled sprays to trailing ants and nest sites (concentrations of workers, brood, and queens) around structures. Secondarily, baits can be utilized, but due to colony size and distribution, baits are less effective than perimeter sprays at alleviating this pest’s nuisance status.

The movement of tawny crazy ants into un-infested areas is aided by human beings (potted plants and other personal belongings). tawny crazy ant colonies reproduce by budding. tawny crazy ants do not have nuptial flights, so cannot move long distances unless their movement is aided by humans.

Because the tawny crazy ant is commonly found nesting in and amongst human debris and trash, it is important, in conjunction with chemical treatments, to maintain a tidy property. If this entails maintaining and cleaning-up the outside environment in an area where the tawny crazy ant already exists, it is critically important to not exacerbate the problem by moving the ant to an un-infested site in infested debris in an attempt to tidy the property.

Report Findings of the tawny crazy ant.

Should Pest Control Operators (PCO) or UGA Extension Agents find what they think to be a tawny crazy ant infestation, it is important to send a physical sample for confirmation of their identification. Send physical samples to Dr. Dan Suiter, UGA Griffin Campus, Department of Entomology, 1109 Experiment Street, Griffin, GA 30223. Call Dr. Suiter at 770-233-6114 or email him.

Local Extension Offices can often help PCOs identify insects or ship samples for diagnosis. Find your local Extension Office here or call (800) ASK-UGA1 from any non-cell phone.

Identification.

See this tawny crazy ant Identification Information from Texas A&M. This website includes a video of the tawny crazy ant in a lawn. There is another similar video of tawny crazy ant in leaves.

Reference.

Tawny Crazy Ant page from the Mississippi Entomological Museum website.

New online book joins the IPM series

IPM bookMatthew Chappell, Associate Professor UGA & Statewide Extension Specialist (Nursery Crops)

The book IPM for Shrubs in Southeastern US Nursery Production Volume 1 is now available via iBooks for viewing on an iPad at the link below and as pdf files for viewing on a laptop, desktop, and most mobile devices at the link below that.

IPM Select Shrubs: Vol. I

IPM_Shrub_Book

Also, our previous book, IPM for Select Deciduous Trees in Southeastern US Nursery Production, is also available in iBooks for viewing on an iPad at the link below and as pdf files for viewing on a laptop, desktop, and most mobile devices at the link below that.

IPM Select Trees

http://wiki.bugwood.org/IPM_book

We will be publishing 4 more volumes of the shrub book over the next few years, with each book covering 4-7 genera of woody ornamentals.