Turfgrass Q & A

Turfgrass Q & A

Worm mounds in bermudagrass. Photo credit Mary Salinas, UF IFAS Extension.

The April 8 program of Gardening in the Panhandle LIVE! was focused on turfgrass, quite a popular topic in the springtime as the weather warms and turf comes out of winter dormancy. Here are some of the questions asked of our University of Florida experts and the links to resources they shared.

To start with, two sites that have comprehensive information are Your Florida Lawn: http://hort.ufl.edu/yourfloridalawn/ and Gardening Solutions: https://gardeningsolutions.ifas.ufl.edu/

Turfgrass Selection

Q. What’s the answer to “I want a lawn like I had up north”? Remotely possible?

A. You can have a nice lawn, but it is going to be different in the panhandle. Don’t expect the same grass species or maintenance.

Q. What grass species is recommended for winter overseeding, and when should the grass be sown?

A. Overseeding has its problems and generally not recommended as it shades out the warm season turf as it is coming out of dormancy in the spring. Overseeding Florida Lawns for Winter Color: https://sfyl.ifas.ufl.edu/archive/hot_topics/lawn_and_garden/overseeding_winter_lawns.shtml

Q. How well do new turfgrass varieties thrive against weeds?

A. A healthy and properly maintained lawn is your best defense against weeds and other pests. Additionally, ProVista is a new cultivar of St Augustinegrass that can tolerate glyphosate so it makes it much easier to kill weeds in the lawn. ProVista is not yet widely available in the panhandle.

Q. How do I get a lawn started?

A. Preparing to Plant a Florida Lawn: https://edis.ifas.ufl.edu/lh012

Establishing a Florida Lawn: https://edis.ifas.ufl.edu/topic_lawn_establishment

Q. Can I have a native lawn? What are some recommended alternatives to a turf lawn?

A. Opinions are divided as to whether St. Augustinegrass is native. See these links for lawn Alternatives:  https://gardeningsolutions.ifas.ufl.edu/lawns/turf-types/alternatives-to-turfgrass.html

https://gardeningsolutions.ifas.ufl.edu/mastergardener/webinars/mg-update-june2018/ffl-lawn-alternative-mg-update-june-2018-handout.pdf

Fertilizing & Weed Control

Q. How long should I wait before fertilizing new sod?

A. Wait 30-60 days before applying fertilizer. See: Homeowner Best Management Practices for the Home Lawn: https://edis.ifas.ufl.edu/ep236

Q. Basic fertilizer for most lawns if no other information is available.

A. 15-0-15

Q. Are weed and feed products effective? Can you use a Weed & Feed like Scott’s Bonus S this late in the year?

A. Weed and feed products are not recommended.

Weed & Feed, Not Foolproof: https://ocmga.wordpress.com/2013/03/11/weed-and-feed-not-foolproof-by-larry-williams-ufifas-extension-agent/

Weed Management Guide for Florida Lawns: https://edis.ifas.ufl.edu/ep141

Lawn Maintenance & Renovation

Q. My husband overwaters the lawn. Remind everyone about correct watering.

A. Homeowner Best Management Practices for the Home Lawn: https://edis.ifas.ufl.edu/ep236

Watering Your Florida Lawn: https://edis.ifas.ufl.edu/lh025

Sprinkler calibration: https://gardeningsolutions.ifas.ufl.edu/care/irrigation/calibrating-your-irrigation-system.html

Q. What to do about bare spots in St Augustine turf in shade?

A. Rough up the ground and put ½ to 1” compost and let the grass fill in or plant plugs. St. Augustinegrass for Florida Lawns: https://edis.ifas.ufl.edu/lh010

Q. When is the best time to overseed? I have a centipede lawn that’s 15-16 years old and I’m trying to bring it back to health.

A. Be sure to be following good practices and centipedegrass should not fail. Overseeding may not be the best option. Centipedegrass for Florida Lawns: https://edis.ifas.ufl.edu/lh009

Q. How do I repair lawn areas ruined by piled up Hurricane Sally debris?

A. Homeowner Best Management Practices for the Home Lawn: https://edis.ifas.ufl.edu/ep236

Q. How do I care for a zoysiagrass lawn?

A. Zoysiagrass for Florida Lawns: https://edis.ifas.ufl.edu/lh011

Q. Should I mulch or bag clippings?

A. Unless you have disease or weed seeds, mulch the clippings onto the turf so you can return the nutrients and water into the soil. Mowing Your Florida Lawn: https://gardeningsolutions.ifas.ufl.edu/lawns/lawn-care/mowing-your-florida-lawn.html

Pest Management

Q. When is the best time to put out a pre-emergence treatment to control and prevent weeds in your lawn (warm and cool season)?

A. Summer Annual Weed Control Timeline: https://sfyl.ifas.ufl.edu/media/sfylifasufledu/escambia/horticulture/Summer-Annual-Lawn-Weed-Control-Timeline.pdf

Winter Annual Weed Control Timeline: https://sfyl.ifas.ufl.edu/media/sfylifasufledu/escambia/horticulture/Winter-Annual-Lawn-Weed-Control-Timeline.pdf

Q. How do I manage chamberbitter in lawns?

A. Chamberbitter: https://hgic.clemson.edu/factsheet/chamberbitter/

Gallery, with the active ingredient isoxoben, has always been the best product to control chamberbitter. Another product, Gemini, adds prodiamine with isoxoben and also provides good control.

Q. How do you get dollar weed under control?

A. Control irrigation. Dollarweed loves lots of water so make sure you are not overwatering. See: https://edis.ifas.ufl.edu/ep389

Q. I used Image to help control Bahia in Centipede. Anything else that we can use?

A. Metsulfuron methyl, 3 applications every 21 days

Q. Which postemergence herbicide is safe and effective for reducing oxalis in a lawn?

A. Yellow Woodsorrel (Oxalis) Biology and Management in Turf: https://edis.ifas.ufl.edu/ep385

Q. What is the best non-poison weed killer?

A. If a product is a weed killer, whether it is organic or synthetic, it is a poison. Alternatives to Synthetic Herbicides for Container Plants & Homeowner Herbicide Guide: https://edis.ifas.ufl.edu/ep464 & https://edis.ifas.ufl.edu/ep575

Q. How do I treat lawn fungus?

A. First you need to determine which fungus, if any, is responsible. Key to Identification of Landscape Turfgrass Disease: https://edis.ifas.ufl.edu/lh064

Then turn your attention to Turfgrass Disease Management: https://edis.ifas.ufl.edu/lh040

Q. How do I diagnose and control mole crickets?

A. Look at this UF guide: https://edis.ifas.ufl.edu/in1021

This video shows how to do the soap flush to scout for mole crickets https://www.youtube.com/watch?v=sx_o4EMXsCo

 

 

Large Patch: Not the Only Rhizoctonia in Town

Large Patch: Not the Only Rhizoctonia in Town

Large patch Rhizoctonia solani (known as brown patch in cool season grasses) is a common disease of many turfgrass species.  It usually occurs during the cooler months from October through May when temperatures are below 80 degrees Fahrenheit.  However, signs and symptoms of large patch and other Rhizoctonia diseases can be observed throughout the summer.  Less common Rhizoctonia species that occur during the summer months are Rhizoctoni zeae and Rhizoctonia oryzae.  Extended periods of turf wetness from excessive rainfall or overwatering provide ideal conditions for the disease to develop and spread.

Rhizoctonia in zoysiagrass

Rhizoctonia in a zoysiagrass lawn. Photo Credit: Matt Lollar, University of Florida/IFAS Extension – Santa Rosa County

This summer in Santa Rosa County, Rhizoctonia has been positively diagnosed in both St. Augustinegrass and zoysiagrass lawns and suspected in a number of centipedegrass lawns.  The disease usually starts as small, yellow patches (about a foot in diameter) that turn reddish brown, brown, or straw colored as the leaves start to die. Patches often expand to several feet in diameter.  It is common to see rings of yellow or brown turf with otherwise healthy turf in the center.  The fungus infects portions of the blades closest to the soil, eventually killing the entire leaf.  Grass blades can easily be pulled off their stems, but roots are not affected by the disease.

Rhizoctonia in a St. Augustinegrass lawn

Rhizoctonia in a St. Augustinegrass lawn. Photo Credit: John Atkins, University of Florida/IFAS Extension – Santa Rosa County

Overwatering and excessive fertilization can both contribute to the development of Rhizoctonia disease.  Improper timing of fertilizer application can also promote disease development.  In the Florida Panhandle, turfgrass is actively growing from April to October.  Slow-release fertilizers are recommended to allow for a more even distribution of nutrients over the course of multiple months.  Recommended fertilizer rates are based on turfgrass species, geographical location, and fertilizer analysis.  Please refer to the UF/IFAS Publication: “Urban Turf Fertilizer Rule for Home Lawn Fertilization” for rate recommendations.

fertilizer chart

Chart excerpted from Florida-Friendly Landscaping publication.

If large patch or another Rhizoctonia disease is confirmed in your lawn, then chemical controls are necessary to keep the disease from spreading.  Fungicide products containing the active ingredients azoxystrobin, chlorothalonil, fludioxonil, flutolanil, iprodione, mancozeb, metconazole, myclobutanil, polyoxin D, propiconazole, thiophanate-methyl, thiram, triadimefon, trifloxystrobin, or triticonazole are viable options for keeping the disease from spreading.  For best results, follow the fungicide label for application instructions.  It’s important to not only treat the affected areas, but also the healthy turf surrounding these areas in order to keep the diseased spots from growing in size.

Unfortunately, turf diseases are often not noticed until large patches of declining and dead turf are noticed.  In these cases when large dead patches exist in the lawn, it is usually necessary to resod these areas.  As with most problems that arise in the landscape, good cultural practices are the most proactive way to mitigate the chances with turfgrass diseases.  The UF/IFAS Florida Friendly Website provides up-to-date solutions and recommendations for caring for Florida landscapes.

What’s Eating My Lawn?

What’s Eating My Lawn?

What’s eating my lawn? Does your grass look ragged in areas, as if someone randomly used a weed-eater here and there? Are you noticing brown patches that have a closely clipped appearance compared to other areas of your lawn? Your turf may be playing host to Tropical Sod Webworm.

Sod webworm damage in a home lawn. Photo courtesy UF/IFAS.

Sod webworm damage in a home lawn. Photo courtesy UF/IFAS.

Sod webworm damage is subtle at first. You have to look closely to notice larval feeding damage. However, an easy indication of their presence is the light tan/brown colored moths, which are the adult stage of the pest. You may see them fly up as you walk through your lawn or if you disturb a nearby bush. The moths do not cause any damage to the turf, but they are depositing eggs, which will result in their offspring, the caterpillars, who do all the chewing damage.

The larvae are gray-green and have spots on each segment. The mature larvae can be up to 1 inch in length. Larvae will curl up in the soil during the day and feed at night. So if you happen to notice caterpillars feeding during the day, it’s probably not sod webworm. You will notice chewed notches along the leaf blade, holes in the leaf and even leaf blade skeletonizing. The older the larvae are, the more they will eat. Damage may start out as a ragged appearance in your turf, which can be hard to diagnose. However, if left unchecked, sod webworm can cause considerable injury to your lawn.

Sod webworm larvae. Photo courtesy UF/IFAS.

Sod webworm larvae. Photo courtesy UF/IFAS.

If you are uncertain of their presence you can always use a soap drench to flush out larvae. Mix 2 tablespoons of dish soap with 2 gallons of water and pour it over a damaged area (about 3 square ft.). The soap mixture will irritate the pest and bring them to the surface so you can easily identify them. If nothing appears in the area tested move to another damaged site and try again. Here is a link to a video that will give more information on identifying Tropical Sod Webworm.

Tropical Sod Webworm is considered a pest of all warm-season turfgrasses. However, St. Augustinegrass is most commonly affected. The best way to prevent a pest infestation is to use proper cultural maintenance practices for your lawn type. However, if the pest does appear, chemical control should be targeting the larvae stage of the pest. There are multiple products marketed to control lawn caterpillars. However, you may want to consider using B.t. (Bacillus thurengiensis), which is a bacterium that will only harm caterpillars and not bother beneficial insects that may be in your lawn. For more information you can contact your local extension office.