During summer months, we often see an uptick of surface and subsurface insects. We can also see an increase of various fungus depending on how dry or rainy our season is. This year, we’re seeing a lot of both. Controlling these issues is not always straight forward. What’s the best insecticide or fungicide? When should you apply? How do you prevent fungus from happening? That’s why we’ve connected with Greg Johnson, an Account Manager out of our Atlanta region. Greg has more than 20 years’ experience in the industry and is an expert on warm-season turfgrass, certified in Turf & Ornamental Pest Management, and can help you find the right solution for combatting issues with insects, weeds, and fungus.
With summer in full swing, now is the perfect time to connect on some of the more common surface/subsurface insects and fungi that we’re seeing this season, as well as effective and fast control solutions to combat them.
Subsurface Insects: White Grubs
Grubs are the larvae of various beetles. This subsurface insect feeds on the roots of turfgrass, leaving the tops to wither and die. Beyond that, they attract all sorts of foraging pests and rodents such as skunks and moles that feed on the larvae.
In heavy infestations, roots are pruned off to the extent that the turf can be rolled back like a carpet. Symptoms include yellowing or browning of the grass and signs of drought stress when moisture levels are good. Grass may also feel spongy when infestations are heavy. I recommend using a curative product at this time called Dylox (Trichlorfon) or Arena (Clothianidin). When using either product, it is imperative to water the product the day of application for 30 minutes. This will allow the active ingredients to work their way down to where the insects are active and treat the infestation. Product rate and number of applications will depend on the development stage of the grub, as well as the desired level of control. Follow the local and state regulations as well as manufacturer recommendations for application.
Surface Insects: Spittle Bugs
Spittle bugs are active in turf and ornamental trees and shrubs (roses, chrysanthemums, clover, strawberries, herbs and other garden plants). They are most common in zoysia and centipede lawns, but you can find them in fescue and other warm-season turfgrasses.
These insects are small about the size of your fingernail, black in color with a pair of orange/reddish stripes across their back. These insects will suck the chlorophyll out of the leaf tissue leaving a pale color. They can also cause plant tissue to lose its shape. When irrigating the turf or plant material it will cause them to jump around and disperse giving away their presence.
In some cases, you will notice a “spittle mass” which resembles spit. These masses can offer protection from some pesticide sprays. I recommend Bifenthrin (Bi-Fen I/T) insecticide spray, I have found this to be the most effective against spittle bugs. After the first application, follow up in 10-14 days to check the population. If you are still seeing these bugs, it may be necessary to do another application.
Fungus: Brown Patch / Large Patch
Brown Patch/Large Patch (Rhizoctonia Solani) is the most common turfgrass disease in the South. It can affect ALL turf species. There are no known species of turfgrass that are currently or entirely resistant to this disease.
It is active in high temperatures (70-90 degrees) and high humidity. This disease causes thinned patches of light brown grass that are roughly circular in shape. These areas can range from a few inches to several feet in diameter. Often the center of the patch will recover, resulting in a doughnut-shaped pattern. With a closer inspection of the grass blades, you will see small, irregular, tan freckles or lesions on the blades, along with a combination of dark brown to black blade borders, and rotted leaf sheaths near the soil surface.
The good news is you can control and even prevent brown patch. The easiest way to do this is to avoid high nitrogen rates. Hudson Valley Natural’s fertilizers, including Jackpot is an excellent choice to use starting in the spring to minimize the chances of brown patch. Other prevention methods include following good lawn care practices. Mow at least once a week and keep your turfgrass watered properly. Long infrequent waterings are the best and water early in the morning when the turf would be naturally wet from dew anyway.
Once brown patch/large patch has established, you can use a fungicide control method to treat it. I recommend an azoxystrobin fungicide like Heritage G or Strobe 50WG. These fungicides will normally last 21-28 days from application. It is important to re-applicate around 21-24 days with a different non-azoxystrobin product. I like to use thiophanate methyl (Cleary 3336f WP) or (T-METHYL 4.5F). Remember, fungicides only arrest fungus pathogens they do not cure them. In some circumstances, it is possible to for some warm-season turf to almost completely recover from this disease but it is not guaranteed.
Remember, rely on the experts at Central to help you with any of your turfgrass or ornamental tree and shrub questions. We stay at the leading-edge of the industry. We have experts on staff at all our local branches and they’re ready to help you grow!
About Greg Johnson
Greg Johnson has more than twenty years of experience in the Green Industry, starting while he was in college in the late 90’s. Through hard work, dedication, knowledge, and a focus on customer service, Greg successfully opened up two successful businesses in the Atlanta-area in turf and ornamental. After growing and expanding these two successful businesses, Greg joined the Central team in 2018. Throughout his career Greg has been has strived for excellence, he has received numerous awards including sales, employee of the year, and branch manager of the year. Licensed in Category 24 and 41, Greg is ready to help you take your turf and ornamental category to the next level.