Every time we have a dry period in spring or summer, I get those predictable calls about some mysterious pest that’s playing havoc in lawns.
Dry spots in lawn. Photo credit: Larry Williams
Without realizing it, the caller usually describes a textbook example of dry spots in a lawn. And many times that’s what the problem areas are – dry spots.
Dry spots are the result of imperfections in an irrigation system. They are revealed during dry weather. Adequate rainfall masks the imperfections in an irrigation system.
Possible imperfections are many. The homeowner may easily fix some irrigation system problems while other problems may require the expertise of a licensed irrigation contractor. There may be too few sprinkler heads for adequate coverage, insufficient pressure to operate each zone, incorrect choice of nozzles or wrongly mixing rotors with spray heads on the same zone. The cause for dry spots may be as simple as a maladjusted spray head, a broken spray head, a plugged nozzle, a tree or shrub blocking the water, grass that has grown over a pop-up spray head, etc.
Regardless of the cause, there are a couple of simple tests that can help confirm that the problem areas are to be blamed on lack of sufficient water vs. a mysterious pest.
First, check the affected areas by taking a soil sample in the root zone. Use a soil probe or shovel to remove a core of soil to a depth of 6 to 8 inches. Visually inspect and feel the soil sample for moisture. Do the same test in an area of the lawn that looks normal and compare the difference. It should be obvious if there is a difference in moisture between the areas tested.
The second test involves placing several empty straight-sided cans such as tuna fish cans in the affected area and several in a “normal” area of the lawn. Then let the irrigation system run long enough to collect some water in the cans. Compare the amount of water collected in the two areas. It should be obvious if there is a difference in the amount of water applied in the areas tested.
These tests are cheaper, less trouble and more environmentally friendly as compared to purchasing and applying pesticides for nonexistent pests as a result of incorrectly diagnosing the problem. If these tests do not identify the problem as lack of water, you may have a lawn pest. But don’t guess.
Occasionally inspect your irrigation system while it’s running for obvious, easily corrected problems such as a maladjusted or broken spray head. The following UF/IFAS Extension publications will help with your inspection. https://edis.ifas.ufl.edu/entity/topic/residential_sprinkler_systems
Applying the right amount of water to the lawn when the turf actually needs water is not always the easiest task for busy homeowners. UF IFAS Extension Escambia County Master Gardener Volunteer Greg Leach shares information about a soil moisture monitoring system that attaches to a home sprinkler system. This can help you apply water to the turf when it is actually needed by measuring soil moisture availability.
As a boy in a small town in Georgia we had a St. Augustinegrass lawn. My dad started the lawn before I was born. That lawn was still doing fine when I left for college at age seventeen. I don’t remember weeds in the lawn during summer months. I do fondly remember winter “weeds” in that lawn.
To see clumps of winter annuals in our yard and in neighbors’ yards was a natural part of the transition from winter to spring. They added interest to what
Blue Easter egg hidden in chickweed. Photo credit: Larry Williams
would have been a plain palette of green. It was expected to see henbit with its square stiff stems holding up a display of small pinkish purple flowers in late winter and early spring. A clump of henbit was a great place to hide an Easter egg, especially a pink or purple one.
Wild geranium, another common winter annual, offered another good hiding place for Easter eggs with its pink to purple flowers. Large clumps of annual chickweed would nicely hide whole eggs. Green colored eggs would blend with chickweed’s green leaves.
Pink Easter egg hidden in crimson clover & hop clover mix. Photo credit: Larry Williams
Crimson clover with its reddish flowers, hop clover and black medic with their bright yellow flowers were good hiding places for Easter eggs. Plus clovers add nitrogen back to our soils.
I never remember my dad using any weed killer, he rarely watered. The lawn was healthy and thick enough to be a deterrent to summer weeds. But during fall and winter as the lawn would naturally thin and go dormant, winter annual weeds would run their course.
I’ve heard that the sense of smell provides our strongest memories. I remember the first mowing of the season with the clean smell of chlorophyll in the spring air. It was refreshing. Once mowed and as the heat took its toll, by late April or mid-May, these winter annual weeds were gone. What was left was a green lawn to help cool the landscape as the weather warmed. The lawn was mowed high as St. Augustine should be, played on and typically not worried with.
Most people have winter weeds in their lawns that let us know spring is near. Perhaps we worry too much with these seasonal, temporary plants that may have wrongly been labeled as weeds. Besides, how long have we been doing battle with these weeds and they are still here. Most lawns have countless numbers of winter annual seeds awaiting the cooler temperatures and shorter days of early winter to begin yet another generation. By May they are gone.
Plants need water. This isn’t an outrageous insight, but the details behind this statement can be more complicated than it might seem. While it is true that plants, like all living things, need water to survive, they don’t all need the same amount and they may need more or less at different times. For a healthy landscape, garden, container planting, or lawn, it’s important to pay attention to the little quirks of watering that may not be immediately obvious.
During the wintertime, temperatures are lower and days are shorter. Less heat and sunlight means water will evaporate much more slowly and the soil will stay wetter. With less heat and sunlight, plants grow at a much slower rate (if at all). This means that irrigation systems set for summertime watering are probably going to keep conditions too damp for many plants during the winter. For example, a St. Augustinegrass lawn might only be able to survive 1 to 5 days without irrigation or rain in the summer, but the same lawn can last 8 to 28 days between waterings in the winter. Consider adjusting your irrigation system or watering schedule to account for seasonal differences. Remember also that a practiced eye can tell when a lawn needs water – folding or curled blades of grass, a dulling of color from bright green to bluish-gray, and footprints that remain in turf rather than springing back are signs of drought stress. Before these signs show up, it may not be necessary or beneficial to water.
Snails love moisture, and an abundance of them may be a sign of too much irrigation.
If plants are overwatered, they often show different signs of distress. Lawns may have more issues with fungal diseases or become patchy, which can let weeds begin to take over. Ornamental plants such as shrubs and trees might show signs of nutrient deficiency or begin to drop leaves, appearing sparse and unhealthy. You may notice an increase in moisture-loving pests as well, such as slugs or snails. Check for watering issues if you notice any of these symptoms.
Cooler weather can be a good time to get outside and do regular maintenance on irrigation systems and plantings. Replace or unclog malfunctioning nozzles, patch
Moisture held against the base of a tree by mulch can eventually damage the plant.
holes in water lines, and adjust irrigation heads that may no longer be pointed in the right direction. Prune back plants that have grown into irrigation sprinkler patterns and may disrupt even watering. Put in new or replacement plants and make any adjustments needed to their irrigation. Lastly, add mulch around plants. This can help retain soil moisture, even out changes in soil temperature, suppress weed growth, and add organic matter to the soil as mulch breaks down. Avoid piling mulch against the base of plants, however, or it will hold moisture against the plant and can promote the growth of molds and other fungi.
Improperly placed or calibrated sprinklers can cause problems.
7 year old Overcup Oak (Quercus lyrata) on the edge of a wet weather pond in Calhoun County. Photo courtesy of Daniel Leonard.
Haunting alluvial river bottoms and creek beds across the Deep South, is a highly unusual oak species, Overcup Oak (Quercus lyrata). Unlike nearly any other Oak and most sane people, Overcups occur deep in alluvial swamps and spend most of their lives with their feet wet. Though the species hides out along water’s edge in secluded swamps, it has nevertheless been discovered by the horticultural industry and is becoming one of the favorite species of landscape designers and nurserymen around the South. The reasons for Overcup’s rise are numerous, let’s dive into them.
First, much of the deep South, especially in the Coastal Plain, is dominated by poorly drained flatwoods soils cut through by river systems and dotted with cypress and blackgum ponds. These conditions call for landscape plants that can handle hot, humid air, excess rainfall, and even periodic inundation (standing water). It stands to reason our best tree options for these areas, Sycamore, Bald Cypress, Red Maple, and others, occur naturally in swamps that mimic these conditions. Overcup Oak is one of these hardy species. Overcup goes above and beyond being able to handle a squishy lawn, it is often found inundated for weeks at a time by more than 20’ of water during the spring floods our river systems experience.
The same Overcup Oak thriving under inundation conditions 2 weeks after a heavy rain. Photo courtesy Daniel Leonard.
The species has even developed an interesting adaptation to allow populations to thrive in flooded seasons. Their acorns, preferred food of many waterfowl, are almost totally covered by a buoyant acorn cap, allowing seeds to float downstream until they hit dry land, thus ensuring the species survives and spreads. While it will not survive perpetual inundation like Cypress and Blackgum, if you have a periodically damp area in your lawn where other species struggle, Overcup will shine.
Overcup Oak is also an exceedingly attractive tree. In youth, the species is extremely uniform, with a straight, stout trunk and rounded “lollipop” canopy. This regular habit is maintained into adulthood, where it becomes a stately tree with a distinctly upturned branching habit, lending itself well to mowers and other traffic underneath without having to worry about hitting low-hanging branches. The large, lustrous green leaves are lyre-shaped if you use your imagination (hence the name, Quercus lyrata) and turn a not-unattractive yellowish brown in fall. Overcups especially shines in the winter, however, when the whitish gray, shaggy bark takes center stage. Overcup bark is very reminiscent of White Oak or Shagbark Hickory and is exceedingly pretty relative to other landscape trees that can be successfully grown here.
Overcup Oak leaves in August. Note the characteristic “lyre” shape. Photo courtesy Daniel Leonard.
Finally, Overcup Oak is among the easiest to grow landscape trees. We have already discussed its ability to tolerate wet soils and our blazing heat and humidity, but Overcups can also tolerate periodic drought, partial shade, and nearly any soil pH. They are long-lived trees and have no known serious pest or disease problems. They transplant easily from standard nursery containers or dug from a field (if it’s a larger specimen), making establishment in the landscape an easy task. In the establishment phase, defined as the first year or two after transplanting, young, transplanted Overcups require only a weekly rain or irrigation event of around 1” (wetter areas may not require any supplemental irrigation) and bi-annual applications of a general purpose fertilizer, 10-10-10 or similar. After that, they are generally on their own without any help!
Typical shaggy bark on 7 year old Overcup Oak. Photo courtesy Daniel Leonard.
If you’ve been looking for an attractive, low-maintenance tree for a pond bank or just generally wet area in your lawn or property, Overcup Oak might be your answer. For more information on Overcup Oak, other landscape trees and native plants, give your local UF/IFAS County Extension office a call!
Nearly everyone dreams of having a perfectly lush, green turfgrass lawn in the backyard. Indeed, lawns provide many benefits to homeowners! A well-managed lawn is an excellent filter of chemical and nutrient runoff, builds soil through the breakdown of clippings, thatch and organisms that exist in turf systems, is aesthetically pleasing and increases property values, reduces ambient air temperatures and provides a durable surface for pets and play! However, none of these turf benefits can be realized if you don’t install and establish sod correctly.Remember these ten tips when planning, installing, and establishing sod to realize your perfect lawn dream!
Choose the Correct Species for Your Site. Not every site is equal. Is irrigation present, or will the turf be on its own? Are you willing and able to provide a higher level of care or will you sacrifice some aesthetic appeal for a lower maintenance turf? These and other questions need to be answered before you buy! Do some homework before settling on a particular grass species and cultivar; they all have merits and drawbacks.
Prepare the Site. Ensure the area you’ll be installing your new sod is weed-free, not compacted, and smooth. Several weeks before installation, apply a non-selective herbicide to “clean” the site of weeds. After existing weeds die, it’s a good idea to till the area or at least “rough it up” with a heavy rake. This helps alleviate site soil compaction which allows easier root initiation from sod to soil. Finally, smooth the site to ensure good root to soil contact and prevent a bumpy surface later.
Time for some water! ‘Tiftuf’ Bermuda sod ready for a mid-lay watering. Hot and dry conditions demand sod be kept moist. Photo courtesy of the author.
Buy Quality Sod. Research where the dealer you purchase sod from sources their grass. Ensure you’re buying turf from a respected operation that follows Sod Production Best Management Practices. Not all farms are equal.
Lay it Quickly. If buying from a retail dealer, make sure their sod is fresh. Sod quality declines rapidly after 48 hours from cutting. Ideally, sod is installed the same day it’s cut on the farm, but not later than the next day.
Water periodically during installation. If installing a large area of turf, periodically wet sod you’ve already laid. Think about the day the sod you’ve laid has had. It was ripped from its home soil, windblown on a trailer en route to your site, laid onto a warm, bare soil surface and is currently baking in the sun waiting on you to finish laying the rest. That’s stressful and a good way to have a crispy brown patch in the new lawn! Ease the sod’s stress by periodically wetting as you lay it. It’s also not a bad idea to lightly moisten the site prior to laying the new sod. Avoid making it muddy.
Mound Soil Around Edges. This prevents the edges of freshly laid turf from drying quicker than the rest of the grass and browning out. It doesn’t have to be a lot, just take a heavy rake and fill in the gap between the soil surface and the leaf blades. Think of it as hiding exposed roots from the sun and wind. Trust me, this step keeps you from having a nice brown ring circumventing your new green lawn!
Pack it Down. You can be fancy with a drum roller partially filled with water or simply use a rake or tamping tool to lightly tamp the grass down. This helps ensure good root contact with the soil, prevents dry patches in the establishing sod, and quickens rooting time.
Almost finished! Remember to tamp down and mound soil around the roots of the edge pieces. Photo courtesy of the author.
Water Correctly. Your new sod needs to be thoroughly watered daily for the first 10-14 days after installation. Remember how stressful the sod laying process is to turf. It takes a little while for sod to recover and initiate rooting into its new home. Don’t miss a day! Following this initial 10-14 day period, back off to once every couple of days for another two weeks or so. After that, the sod should be rooted in nicely and be able to rely on regular, as needed, lawn irrigation intervals.
Stay Off It! Minimize traffic on new sod for several weeks after installation. Roots are establishing during this time and are extremely vulnerable to disturbance until anchored. I know you’re ready to enjoy your new lawn, but you’ve come too far now to mess it up!
No Fertilizer for 30-60 days! Plants without roots have a hard time taking up nutrients. Therefore, it makes sense that until sod has firmly anchored into place and established a new root system, fertilizer application should be withheld. Fertilizer applied during the initial establishment period will likely be wasted and leach through the soon-to-be rootzone and could even burn fragile new roots. Also, avoid using a starter fertilizer for the same reason – there aren’t any roots to take up the nutrients.
‘Tiftuf’ Bermudagrass sod being watered after installation is finished. Do this daily for 10-14 days following installation. Photo courtesy of the author.
By following these ten tips, you’ll be well on your way to a perfect lawn! For more information on these and other lawn care topics, contact your local UF/IFAS Extension Agent and consult The Florida Lawn Handbook, a research-based publication written by UF/IFAS Extension specialists.