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Why A One Size Fits All Approach to Lawn Care is a Bad Idea

Regardless of what the tag says one size does not fit all. As with clothing, a piece will undoubtedly be too large for some and too small for others. Trying to go with a “one size fits all” approach to lawn care will lead to the same kind of frustration and disappointment as an ill-fitting garment.

All turfgrass is not created equal. Thus management of our various turf species requires different methods. It is common for a homeowner to be unaware of what type of turfgrass they have – it’s all grass after all – what difference does it make? Misidentification leads to problems because proper management for one type may be counterproductive to another type. In order to create a practical turf management plan, it is critical that the species of grass is properly identified.

Although many grasses look similar it is important to know exactly what kind you have to maintain it properly. This photo shows Empire Zoysia. Photo credit: Julie McConnell, UF/IFAS

Why is it important to know the species of turf in a lawn?

Two of the most common mistakes extension agents observe is excessively low mowing height of St. Augustinegrass  and over-fertilizing Centipedegrass. Both of these errors can reduce turfgrass vigor and decrease its tolerance to pest issues. Another potential maintenance pitfall is using a herbicide that is not labeled for use on a given type of turfgrass. Several popular herbicides available on the market can cause damage to St. Augustinegrass and/or Centipedegrass.  Thus turf can be inadvertently killed by herbicides when they are applied to the wrong species.

Before a lawn maintenance plan is developed, be sure to know what type of grass is present and then follow UF/IFAS recommendations for proper care. If assistance is needed with identification, contact your local extension office.

To learn more about lawn care, visit this site or plan to attend “Caring for Your Florida Lawn” at the UF/IFAS Extension Bay County office on April 8th. For more details call 850-784-6105.

Plan to Reduce Summer Weeds

Plan to Reduce Summer Weeds

Remember last summer? The hot, dry days.  Grass drying up and turning brown.  Yet, the weeds are green and doing fine.  However, every herbicide label warns against applying when the temperatures are above 85 degrees and especially under drought conditions.  Those weeds flourished and dispersed seed everywhere.  Now, they are just sitting there ready to sprout again.

It’s time to start thinking about weed prevention.  Pre-emergent herbicides need to be applied prior to seed germination.  Late winter is the time to focus on summer annual weeds.  The narrow window of application is challenging.  Homeowners often wait too late into spring to put out preventative products.  A general rule of thumb for pre-emergent herbicide timing is February 15 – March 1 in North Florida.

However, weed seeds germinate in response to soil temperature, not calendar dates.  By monitoring day time temperatures, one can determine a more effective application date.  When there are 4-5 consecutive days that reach 65 to 70 degrees weeds will germinate.  This generally coincides with the first blooms appearing on azaleas and dogwood.  With a warm winter it may occur as early as mid-January.

Some of the active ingredients in pre-emergent herbicides include dithiopyr, isoxaben, oryzalin, pendimethalin, prodiamine and simazine.  Always read the label for specific weed controlled and observe all directions, restrictions and precautions.

Weed and feed products that contain nitrogen are not suitable as pre-emergent herbicides.  Irrigation before and after application is necessary to activate these products.  The chemical binds to soil particles, creating a barrier that remains effective for 6-12 weeks.  Reapplication will be necessary for season long control, especially with constantly fluctuating winter temperatures.  Now is the time to purchase pre-emergent herbicides and prepare to apply them. For more information on weed control in lawns go to: http://edis.ifas.ufl.edu/ep141

Helping Turfgrass Overcome Herbicide Injury

Helping Turfgrass Overcome Herbicide Injury

Dr. Ramon Leon, Extension Weed Specialist, West Florida Research and Education Center

Herbicides simplify weed management by allowing you to cover extensive areas in a relatively short time, and reduce the need for time-consuming control practices such as hand weeding. Additionally, many herbicides have the advantage of selective control. Selective herbicides are those that kill weeds without significantly injuring the desired plant. In turfgrass, selective herbicides are particularly important because we do not have the option of using cultivation or non-selective herbicides, as is commonly done in other agricultural systems such as row crops and orchards.

A common misconception is that when a herbicide is registered for use on a given turfgrass species, this herbicide has little negative effect on the turf. In reality, even when the herbicide is registered for a specific turfgrass species, it can cause a certain level of injury. If the herbicide is applied at the recommended label rate, and the growing conditions are ideal, the turfgrass will only suffer minor, temporary injury that may go completely unnoticed. Conversely, the weeds that are susceptible to the herbicide will be severely affected resulting in the desired control.

Over the last few summers, there has been an increase in complaints about herbicide injury on sod farms, golf courses, and home lawns after applications of herbicides, especially during the summer months. Many of those complaints originated from situations in which the application was done properly, using the recommended label rate, and thus the level of injury observed was not justified. After studying all these cases, it was determined that at the time of herbicide application the turf was under a moderate level of stress, but not high enough stress to cause visible symptoms. However, when the herbicide was applied the combined effect of the existing stress, and the stress caused by the herbicide made it harder for the turf to maintain the desired quality. For example, Figure 1 below shows that the turf looked fine before the application (A), but after the herbicide was applied, there was a significant loss in turf cover and quality (B). The interesting aspect is that the injury was not present across the entire treated area, but only on patches (C). Those patches corresponded with sand pockets where soil moisture, especially on hot days, was considerably lower than the rest of the area. In that particular case, the irrigation system was providing enough water to help the turf tolerate the moderate stress of high temperatures and limited moisture, but not enough for the turf tolerate the combined stress that occurred after the herbicide was applied.

Figure 1. Centipedegrass growing during the summer in Florida before herbicide application (A), 3 weeks after herbicide (sulfentrazone and metsulfuron-methyl) application (B). Herbicide injury pattern with highlighted areas showing where sand pockets caused drought and heat stress that contributed to herbicide injury (C).

Figure 1. Centipedegrass growing during the summer in Florida before herbicide application (A), 3 weeks after herbicide (sulfentrazone and metsulfuron-methyl) application (B). Herbicide injury pattern with highlighted areas showing where sand pockets caused drought and heat stress that contributed to herbicide injury (C).

 

In Florida, there are a combination of environmental factors such as high temperatures and sandy soils that can create stressful conditions limiting turfgrass growth, especially when irrigation is not sufficient to keep the turf hydrated.  Furthermore, we also experience periods of excess rainfall, and areas of turf growing under shade. Additionally, pest problems that affect roots and leaves are frequently found in our state. All these conditions affect turfgrass health and its ability to tolerate herbicide applications. For these reasons, turf producers and managers need to be proactive to help turfgrass overcome the injury that herbicides might cause. To achieve this goal, you need to follow five simple steps:

1) Identify weed problems early. Most weed problems will start in the spring for summer weeds and in the fall for winter weeds. Controlling them when they are small not only increases the effectiveness of our applications, but also allows us to implement our control when the turfgrass is less likely to be stressed.

If herbicide applications are needed when conditions might be stressful for the turf (high temperatures and/or dry conditions)

2) Make sure irrigation is adequate (increase frequency or duration if needed) for up to three weeks following application.

3) Reduce mowing frequency and increase mowing height 0.5 inches for up to 3 weeks following a herbicide application, to allow the turfgrass to continue producing energy to support its recovery. Mowing too short and too frequently immediately after the application weakens the turfgrass.

4) Fertilize with a small amount of nitrogen (0.25 to 0.5 lb N/acre) a week or two after herbicide application to help the turf recover and produce new leaves.

5) If the turfgrass is suffering from serious pest problems (pathogens, nematodes or insect infestations) do not apply herbicides on the affected areas until the turfgrass has recovered.

Maintaining optimal turfgrass growth is the best way to ensure that herbicide applications will maximize weed control while still protecting the health and aesthetics of your turfgrass.

For more information on growing turfgrass in Florida, please see the following:

Florida Lawn Handbook

 

 

Dr. Ramon Leon, Extension Weed Specialist, West Florida Research and Education Center

 

How to Water to Establish a Lawn

How to Water to Establish a Lawn

MICROIRRIGATION - Image Credit UF/IFAS Extension

MICROIRRIGATION – Image Credit UF/IFAS Extension

When watering to establish a lawn or when renovating (redoing, patching, reestablishing, starting over, etc.) a lawn, we normally call for 2-3 “mists” throughout the day for the first 7-10 days until roots get established. These are just 10 minute bursts. Then back off to once a day for about ½ hour for 7-10 days. Then go to 2-3 times a week for about 7 days. By then your lawn should be established.

If we are experiencing adequate rainfall, you may not need to irrigate. Rain counts. But in the absence of sufficient rain, you’ll need to provide enough water at the correct time to allow your new sod to root – hence, the above directions.

A well designed and correctly installed irrigation system with a controller, operated correctly, helps to achieve uniform establishment. It can be difficult or impossible to uniformly provide sufficient water to establish a lawn with hose-end sprinklers, especially if the lawn is sizeable and during dry weather. Most people are not going to do the necessary job of pulling hoses around on a regular basis to result in a well-established lawn.

Too much water will result in rot, diseased roots and diseased seedlings and failure. Too little water will result in the sod, seedlings, sprigs or plugs drying excessively and failure to establish. The end result at best is a poorly established sparse lawn with weeds. Or complete failure.

There is no substitute or remedy for incorrect irrigation when establishing a brand new lawn or when renovating an entire lawn or areas within a lawn.

It would be wise to not invest the time and money if the new lawn cannot be irrigated correctly. Taking the gamble that adequate (not too much, not too little) rainfall will occur exactly when needed to result in a beautiful, healthy, thick, lush lawn is exactly that – a gamble.

An irrigation system is nothing more than a tool to supplement rainfall. As much as possible, learn to operate the irrigation controller using the “Manual” setting.

The above schedule should help when planting a lawn from seed, sprigs, plugs or sod.

For additional information on establishing and maintaining a Florida lawn, contact your County UF/IFAS Extension Office or visit http://hort.ufl.edu/yourfloridalawn.

Zoysiagrass Becoming More Popular in the Panhandle

Zoysiagrass Becoming More Popular in the Panhandle

If you’ve been researching lawn grass options recently, you’ve probably come across a not so traditional variety known as zoysiagrass. There’s no mystery why zoysiagrass has become a hit with lawn enthusiasts in the Panhandle. This variety is a great choice for coastal, warm weather climates. However, there are always management practices that need to be carefully considered, before deciding on a lawn grass variety.

Zoysiagrass was introduced to the U.S. from Asia around the early 1900’s. The grass has mostly been used for turf applications, especially on golf courses and other athletic fields. However, in recent years, breeding advances have made this variety a viable option for homeowners. Some of these improvements involve insect resistance and fast establishment periods.

Except for one species, zoysiagrasses must be planted by sod, plugs, or sprigs. Zoysia japonica is the only species commercially available in seed form. Zoysiagrass is a not a cold hardy plant. It’s the first grass variety to turn brown under cold temperatures and is slow to turn green once warmer temperatures arrive. Probably the most attractive quality of zoysiagrass is the ability to grow in virtually any soil, ranging from sandy to clay, acidic or alkaline. Moderately shaded locations are also acceptable for zoysia. Zoysiagrass is extremely drought tolerant. The plant’s root system has a great adaptation to combat drought conditions. Since the root system is very deep, it is able to maximize soil moisture potential.

Figure 1. Large (brown) patch disease caused by Rhizoctonia solani. Credit. J. Bryan Unruh, UF/IFAS.

Figure 1. Large (brown) patch disease caused by Rhizoctonia solani.
Credit. J. Bryan Unruh, UF/IFAS.

Zoysiagrass is not a silver bullet for lawn problems. It encounters weed and insect problems as well. The most formidable disease of zoysiagrass is large brown patch. This disease is caused by the fungal pathogen, Rhizoctonia solani. The disease begins in small patches that turn from yellow to brown. It’s common to see these patches with healthier grass in the center. The pathogen is most active when soil temps fall between 65-75°F. This generally correlates with the fall season and then throughout the following spring in the Panhandle. Zoysiagrass is no more susceptible to the disease as any other grass, but the recovery time is lengthy. With this being said, a proactive fungicide regimen is recommended.

Zoysiagrass also responds better to smaller quantities of fertilizer applied more frequently rather than supplying larger quantities infrequently. UF/IFAS Extension recommendations state that zoysiagrass should receive three applications per year in the Panhandle region.

If you are looking to seed or sod your landscape, zoysiagrass may be an option to consider. Best management practices influence the overall health and quality of your lawn and reduces its susceptibility to disease. Take these practices into consideration when deciding on a lawn grass.

Please visit Florida Friendly Landscaping, http://fyn.ifas.ufl.edu/, for more information on maintaining your landscape.

Supporting information for this article can be found in the UF/IFAS EDIS publication “Zoysiagrass for Florida Lawns” by J. Bryan Unruh, L. E. Trenholm, and J. L. Cisar: http://edis.ifas.ufl.edu/pdffiles/LH/LH01100.pdf

An Equal Opportunity Institution. UF/IFAS Extension, University of Florida, Institute of Food and Agricultural Sciences, Nick T. Place, Dean for UF/IFAS Extension. Single copies of UF/IFAS Extension publications (excluding 4-H and youth publications) are available free to Florida residents from county UF/IFAS Extension offices.