The lawn is a source of pride for most and anything out of the ordinary causes alarm. Now image finding something that looks like lumpy green jelly in your turfgrass and it doesn’t go away. You try raking it, spraying it, covering it, and it still comes back time and time again. One of the things we see in late spring/early summer turf is a reemergence of cyanobacteria (Nostoc), sometimes confused with algae because of green coloring and this remains all summer long.
Dehydrated cyanobacteria in a centipedegrass lawn.
Unlike normal bacteria that needs a food source, cyanobacteria contains chlorophyll and produces its own food source through photosynthesis which allows it to grow on bare sandy soils, fabric mats, concrete sidewalks, plastic, and yes even your lawn. Besides the green pigment, it also produces a blue pigment and is why we call it cyanobacteria which means blue-green bacteria. In addition to photosynthesis, cyanobacteria can also fix nitrogen, and are believed to produce cyanotoxins and allelopathic compounds which can affect plant growth around them.
Cyanobacteria are considered one of earth’s oldest organism and they have tremendous survival capabilities. They can dry out completely, be flat, flaky, black-green dried particles in your lawn and once rehydrated, spring back to life. If you happen to notice it spreading throughout your yard, remember that pieces of the organism can stick to your wet shoes or lawnmower tires and be transported unintentionally.
The question then becomes how to control the cyanobacteria and reclaim your turfgrass. The first solution is to have a healthy lawn. Cyanobacteria likes poorly-drained compacted soils. This same condition is unfavorable to turf growth and why you end up with bare spots and establishment. Reduce soil compaction by using a core aerator, and then adding organic matter. This will increase drainage, gas exchange, and encourage microorganism populations which I like to call soil pets. Spike aerators only push the soil particles aside and don’t really loosen as well. Try to reduce low lying areas in the lawn where water sits after rainfall and irrigation. You might have to till and reestablish those areas of the yard.
The same cyanobacteria pictured above 24 hours after being rehydrated in a petri dish of standing water.
Controlling the amount of water Mother Nature gives us and humidity levels during summer is not possible, but you can control your irrigation whether it be automatic (sprinkler system) or hand-watered. During the rainy season, you should be able to get by with only rainfall and shut off your system. If needed during extended dry weeks, it is easy enough to turn the system back on. It is thought that cyanobacteria likes phosphorus which is another reason to use little to no phosphorus in your lawn fertilizers.
As you begin to rid your lawn of cyanobacteria, remember when fully hydrated it forms a slippery surface so be careful walking on it. Cultural practices will be more effective in controlling the spread versus using chemical methods. Cultural solutions are safer for your lawn, yard and all of the wildlife that visits. If you need help with your cyanobacteria, please contact your local Extension office and we are always happy to assist.
A special thanks to Dr. Bryan Unruh, UF/IFAS for his assistance in identifying the cyanobacteria.
For additional information, please read the sources listed below.
Need tips on planting and caring for trees? The primary focus in care of your newly planted tree is root development. It takes several months for roots to establish and newly planted trees and shrubs do not have a very strong root system. Start by digging the hole in a popcorn bowl shape. Once planted, backfill around the root system, but be careful not to compact the soil as this will hinder root growth. Be sure to keep the topmost area of the root ball exposed, about one to two inches. A layer of mulch will be applied here.
Frequent watering is much needed, especially if you are planting in the summer. Water thoroughly, so that water percolates below the root system. Shallow watering promotes surface root growth, which will make the plant more susceptible to stress during a drought. Concentrate some of the water in a diameter pattern a few feet from the trunk. This will cause the root system to grow towards the water, and thus better establish the root system and anchor the tree.
Figure: A Traditional Staking Option. Credit: Edward F. Gilman, UF/IFAS Extension.
Mulch is important in the conservation of soil moisture. Pine needles, bark, wood chips, and other organic materials make a great mulch. A three inch layer of mulch will usually suffice. It’s important to keep the mulch a few inches from the trunk as mulching too close to the tree trunk can cause rot.
You should always prune the bare roots of trees during planting. These exposed roots in containers can be damaged in shipping and removing some of the roots will help trigger growth. Pruning some of the top foliage can also reduce the amount of water needed for the plant to establish, as well. Trees and shrubs grown and shipped in burlap or containers usually need very little pruning.
Newly planted trees often have a difficult time establishing if the root system cannot be held in place. Strong winds and rain can cause the plant to tip over. Avoid this by staking the plant for temporary support. A good rule of thumb to determine staking need is if the trunk diameter measures three inches or less, it probably needs some support! Tie the stake to the plant every six inches from the top. However, only tie the trunk at one spot. Don’t tie too tightly so that the tree has no flexibility. This will stunt the growth of the tree.
Following these tips will help ensure your tree becomes well established in your landscape. For more information please contact your local county extension office.
Information for this article can be found in the UF/IFAS EDIS publication: “Planting and Establishing Trees” by Edward F. Gilman and Laura Sadowiski: https://edis.ifas.ufl.edu/pdf%5CEP%5CEP31400.pdf
Supporting information also provided by UF/IFAS Extension Forestry Specialist Dr. Patrick Minogue, of the North Florida Research Education Center in Quincy, Florida.
Q. One of my two fig trees has produced a few figs. The other one, which is the largest and healthiest tree, has never had a fig on it. Both where planted six years ago. Why is it not producing?
Mature fig tree with fruit. Photo credit: Larry Williams
A. It may be a matter of age and being overly vigorous. When a fruit tree is younger, it puts most of its energy into producing leaves and shoots. Until the plant becomes mature and slows down in the production of leaves and shoots, it will produce few to no fruit. It may take a year or two more for your tree to slowly and gradually switch from producing mostly leaves and shoots to producing and maturing some fruit. Patience is needed.
Be careful to not overdo it in fertilizing and/or pruning your fig tree. Too much fertilizer, especially nitrogen, or severely pruning the tree will result in the tree becoming overly vigorous at the expense of setting and maturing fruit. This includes fertilizer that the tree may pull up from a nearby lawn area. A tree’s roots will grow outward two to three times beyond its branch spread into adjacent lawn areas.
The end result of being heavy handed with fertilizing and/or overdoing it in pruning is the same – it forces the plant to become overly vigorous in producing leaves and shoots at the expense of producing and maturing fruit.
In addition, the following is taken from an Extension publication on figs and includes the most common reasons for lack of fruiting, in order of importance.
Young, vigorous plants and over-fertilized plants will often produce fruit that drops off before maturing. If plants are excessively vigorous, stop fertilizing them. Quite often, three of four years may pass before the plant matures a crop because figs have a long juvenile period before producing edible quality fruit.
Dry, hot periods that occur before ripening can cause poor fruit quality. If this is the case, mulching and supplemental watering during dry spells will reduce the problem.
The variety Celeste will often drop fruit prematurely in hot weather regardless of the quality of plant care. However, it is still a good variety to grow.
An infestation of root-knot nematodes can intensify the problem when conditions are as described in item 2.
You could have a fig tree that requires cross-pollination by a special wasp. This is a rare problem. If this is the case, then it will never set a good crop. The best way to resolve this is to replace the plant with a rooted shoot of a neighbor’s plant you know produces a good crop each year.
Lawn areas come in all sizes and shapes. Some are large open expanses providing long views and others are smaller versions surrounded by shrubs and trees creating a more private and secluded setting. There are a number of reasons for reducing the size of a lawn with some coming into play with your decisions. A home lawn is often an important part of the landscape that provides a place to play outdoors from picnicking, tossing the ball to taking a quite stroll.
Maintaining a healthy lawn is important to an overall performance of this part of the landscape. Several factors are involved in the success in keeping a strong and resilient lawn. Understanding the needs of a grass to remain healthy involve soil testing to address soil pH and nutrient needs plus water challenges. Misuse of fertilizer and over irrigation can be costly to you and to the overall health of the lawn. These decisions can lead to reducing lawn size to managing cost or removing underused areas.
There are big benefits to reducing your lawn from saving time in mowing, trimming and other manicuring needs to saving energy costs involving the lawn mower not to mention reducing pollution from the mower or weed eater. The reduced amounts of pesticides needed to manage weeds and disease to the lawn saves time and money.
Another way to look at the reducing the size of our lawn is there will be more space for expanding plant beds and potential tree placement. These settings increase the opportunities for a more biodiverse landscape providing shelter, protection and food options for birds and other wildlife.
Photo Courtesy: Stephen Greer
The lawn can serve as a transition space that leads from one garden room space to another, while still offering a location to bring the lawn chair out to enjoy all that is around your lawn. Lawns and the landscape are ever changing spaces, especially as your trees and shrubs grow and mature to sizes that can directly impact the lawn performance. Often levels of shade will diminish edges and other areas of the lawn. This often will define the reduction of the lawn size moving going forward. Just remember that lawns and landscapes occupy a three-dimensional space involving the horizontal, vertical and overhead spaces. Just look around and think about what is best for you, your family and the setting.Are you more interested in developing other parts of the landscape? With many of us spending more time at home over the last year plus it gave time to think about the outdoor areas. Growing our own vegetables may be a new or expanding part of the landscape with the use of raised beds or interplanting into the existing landscape. Gardening can assist in reducing stress while at the same time providing that fresh tomato, lettuce, herbs and other fun healthy produce.
What ever your decisions are enjoy the lawn and landscape. For additional information, contact your local University of Florida IFAS Extension office located in your county.
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.
