by John Wells | Jul 1, 2011
Beginning in 2007, the US Senate, in support of the North American Pollinator Protection Campaign, declared the last week of June as “National Pollinator Week.” As humans, we depend on pollen-moving animals for one out of every three bites of food. Without birds, bees, bats, beetles, butterflies and various other animals, many flowers would fail to reproduce. In Florida, there are numerous native plants that serve as hosts for these pollinators. One of the favorites, due to its heavy flowering over the summer, is Buttonbush (Cephalanthus occidentalis). It is a semi-aquatic woody shrub to small tree form. It develops white golf-ball-sized clusters of fragrant flowers that attract various pollinating animals. Bees of various species, several different wasps, assorted moths and butterflies, flies and even hummingbirds scramble for the flowers’ sweet treat within each of the trumpet shaped flowers.
Red Admiral butterfly on a buttonbush flower cluster. Photo Credits: Sheila Dunning
The pincushion like flower balls of the Buttonbush stand on two inch stalks in clusters arising from stem tips and leaf axils. They are produced over a long period in late spring and summer. The flowers give way to little reddish-brown nutlets which persist on the through the winter. Buttonbush seeds are important wildlife food, especially for ducks; and the dense, impenetrable tickets provide nesting and escape cover for many wetland birds and herptiles (reptiles and amphibians). Buttonbush is a fast-growing wetland plant that can be grown in a naturalized landscape if given supplemental water during dry spells. It is at its best, through, in an area where the soil is frequently wet and can tolerate soggy soils. Buttonbush is not drought or salt tolerant. The deciduous shrub grows well in full sun to partial shade on soils that are acidic to slightly alkaline. The leaves of Buttonbush turn yellow in the fall before dropping off. While short-lived, requiring rejuvenation pruning to improve its longevity, Buttonbush (Cephalanthus occidentalis) serves a critical role to wildlife in the wetland habitat. Deer browse the foliage and twigs. Ducks, especially the mallard, eat the seeds. And, the summer flowers attract bees, butterflies and moths that are wonderful pollinators.
by John Wells | Jul 1, 2011
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Ken Rudisill
Horticulture Agent
Bay County Extension
krru@ufl.edu
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Last month, as I was driving to work, I noticed a Pindo Palm that was definitely dying, or should I say, it was dead. I wondered what killed the tree. As I drove by I stopped and I quickly figured it out. The tree had succumbed to Ganoderma butt rot.
Diseased palm on the left, healthy palm on the right. Photo Credits: Dr. M.Elliott,UF/IFAS
Ganoderma butt rot is caused by a fungus (Ganoderma zonatum) that eventually rots the lower portion of the palm. This fungus is not a primary fungus to other plants, just palms.
Stages of conks. Photo Credits: Dr. M. Elliott, UF/IFAS
Even though other palms may show wilt or general decline, the disease can be confirmed by the presents of conks on the trunk. Conks are firm, shelf-like structures that are attached to the lower part 4-5 feet of the palm. They start out as a whitish looking button on the palm then develop a half-moon shape with the straight side attached to the palm.
Confirmation of Ganoderma butt rot can only be made once the conks appear on the trunk, or when the palm is cut down and internal rotting of the trunk is noticed.
The conk produces and releases the fungal spores. The spores become mixed in the soil. The fungus germinates and grows over the roots of the palm. The fungus then enters the woody trunk tissue. If an infected palm is transplanted, the soil in the transplant site may be contaminated with the fungal spores. It is recommended to remove the conk(s) of an infected palm before you remove the palm. This is to prevent the spreading of the spores. Place a plastic baggie over the conk then break it off the palm. Put the baggie in the trash for disposal in the landfill or incinerator.
There are no cultural or chemical controls for infected palms or preventing the disease.
As soon as the conk(s) are noticed, you should remove the palm. Remove as much of the stump and soil as possible to help prevent the spores from attacking other palms that might be nearby. I had seen a grouping of 20 palms planted in a group where several of the palms were infected. The chances were that all 20 could eventually be infected.
It is not recommended to plant another palm in the same place since the spores can survive in the soil. Other trees such as oaks, pines, maples, can be planted in that area.
by John Wells | Jul 1, 2011
During the summer months, landscapes are alive with insect activity. The majority of insects found in home landscapes are not harmful, although the sight of a few may cause some concern. One insect appears to be threatening but is not is the cicada killer, the largest wasp in Florida.
Burrow made by the female Cicada killer. Photo Credits: Beth Bolles, Horticulture Agent
During the warmer months, female cicada killers make ground burrows that consist of several cells for raising a few young. There is an entrance hole, which often remains open, surrounded by a small mound of soil on one side of the entrance. The female makes this ground burrow after mating and then captures cicadas to add to the individual cells. The cicadas will serve as food for the developing wasp larvae that emerge from laid eggs.
A cicada killer wasp trying to carry home a cicada that has been paralyzed. Photo Credits: Zachary Huang, MSU, Department of Entomology
Although the females are able to sting, they are not overly aggressive wasps. The males do make more aggressive flights around people but are unable to sting. When enjoying your landscape, just be aware of ground burrows and the flight of the female wasps into the burrows. If you are lucky, you may even see a wasp with a cicada in tow.
Cicada killers should not be treated in most landscapes. If you are unable to tolerate the wasps, you may reduce their habitat by covering open sandy areas with mulch or a groundcover. This does not completely prevent their ability to nest but will certainly reduce suitable nesting spots. For more information on cicada killers visit: http://edis.ifas.ufl.edu/in573.
by John Wells | Jul 1, 2011
The long, hot days of summer means they you are likely to encounter greater insect populations. Careful routine scouting and recognizing damaging insects and their beneficial predators can help reduce the need for applying insecticides.
Chinch bugs
Chinch bugs love St. Augustinegrass lawns. The adults of this destructive insect are only about 1/5 of an inch long. They are black with what appears to be a white “X” across their backs where their wings fold over. The immature nymphs may be pink to orangey brown with a single white line across their backs.
The older nymphs (left) look similar to the adult (right). Photo Credits: Theresa Friday, Santa Rosa County Extension
An indication of an early infestation is a subtle yellowing of the leaf blades. This is quickly followed by a thinning of the canopy and eventual death of the turf. These insects are somewhat unique in that they prefer hot sunny areas of the lawn over shade so their injury symptoms generally appear in an open area first.
To scout for these tiny insects in your lawn you will need to part the turf canopy to the soil surface along a line where there is a change from damaged yellowing turf to healthy green turf. They move rather quickly, so keep an alert eye for their scurrying back into the turf.
Carbaryl (Sevin®), cyfluthrin (Bayer Advanced Powerforce® Multi-Insect Killer), lambda-cyhalothrin (Spectracide® Triazicide® Insect Killer Once & Done!) and permethrin are labeled insecticides for their control.
Mole crickets
Mole crickets are not nature’s most beautiful insect specimens. Adults are odd-looking light brown crickets. The front legs are short, flat, and shaped like miniature shovels well equipped for digging in your yard. The immature insects, or nymphs, look the same as the adults, just smaller. Both, however, feed on the grass roots.
Mole cricket Photo Credits: Theresa Friday, Santa Rosa County Extension
Walking across your grass may give you a hint to an infestation. The sod will have an unusual fluffiness to it. Closer examination will reveal holes in the ground about the size of a pencil. Small burrowing trails can also be seen.
However, we always want to confirm the presence of mole crickets. Mix two tablespoons of lemon liquid dishwashing soap in two gallons of water in a sprinkling can, and pour the solution onto a two by two foot section of affected turf. If two to four mole crickets emerge within four minutes after applying the soap solution, insecticide use may be justified.
For more information on how to treat for mole crickets, review a University of Florida online publication at http://edis.ifas.ufl.edu/lh034.
Sod webworm
Whenever small brown moths fly up as you mow, caterpillars are not far behind. The moths are there laying eggs and the caterpillars show up two to three weeks later.
Sod webworms eat leaf blades leaving a “notched” appearance Photo Credits: Theresa Friday, Santa Rosa County Extension
Young caterpillars chew notches along the edge of the leaves. This creates a ragged appearance that may be hard to notice at first. Mature caterpillars eat a lot before they pupate and consume patches of turfgrass down to the crown. Because the turf looks scalped so quickly, people think that the damage occurs “overnight.” Several caterpillar species can be turfgrass pests, including the tropical sod webworm, the fall armyworm, and the striped grass looper.
Caterpillars can sometimes be seen, along with their frass, just on the surface of the soil Photo Credits: Theresa Friday, Santa Rosa County Extension
For more information on lawn caterpillars and your control options, visit the University of Florida “Lawn Caterpillars” online publication at http://edis.ifas.ufl.edu/IN608 or call your local Extension Agent.
by John Wells | Jul 1, 2011
I’ve seen people use herbicides to control weeds in an old, declining lawn. Then, with all the weeds gone, the lawn’s owner suddenly realized that he or she had no lawn left. Sometimes the best solution is to start over. Many older, thinning, declining, weedy lawns need to be reestablished. As lawns decline and thin, the weeds move in.
Weedy lawn that needs renovating Photo Credits: Larry Williams
When you reach the point where there is less than sixty percent desirable cover, reestablishment should be considered.
In the process of redoing a lawn, attempt to determine why the lawn declined and correct mismanagement practices that were contributing factors in the lawn’s demise.
Common causes for lawn decline:
Soil compaction – Mowing equipment, vehicles and foot traffic (from adults, children and pets) all result in the soil becoming compacted within a lawn. Compacted soil results in less water and oxygen getting to the lawn roots and less than favorable growing conditions for the roots.
Nutrient imbalances – Routine fertilization can result in some fertilizer elements building up to excessive levels while other elements may be lacking. It’s common to find high levels of phosphorus in older lawns. Phosphorus does not leach readily even in our sandy soils. Other elements such as potassium leach readily. Over time, we’ll end up with too much of some nutrients and too little of others, which contribute to growth difficulties and possible decline in our lawns.
Tree competition – Trees and larger shrubs can compete with a lawn. As a tree gets larger with time, it becomes more competitive with lawn grass. The tree’s demand for water and nutrients increases as it becomes larger. Its root area becomes more extensive and it progressively produces more shade. Lawns usually thin significantly in association with older, large trees and shrubs.
Root pests’ numbers may slowly build to damaging levels as a lawn ages. Some common examples include nematodes (microscopic roundworms), soil inhabiting fungi such as Gaeumannomyces (take-all root rot) and ground pearls (a scale insect found in soil).
Improper lawn maintenance practices may be a contributing factor in the decline of an older lawn. Common contributing factors to a lawn’s demise include routinely mowing too low, excessive fertilization and irrigating incorrectly.
Sometimes herbicides are only a “band aid” approach when dealing with an old, mismanaged lawn.
by John Wells | Jul 1, 2011
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Carrie T. Stevenson
Coastal Sustainability Agent
Escambia County Extension
ctsteven@ufl.edu
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One of the first instincts of many homeowners when they see a big storm in the Gulf is to start trimming limbs and removing trees. The recent tornado devastation throughout the Southeast and Midwest has also caused many people concern about having a mature tree in their yard. While it is true that falling trees and limbs can cause significant damage to a home and property, it is wise to fully evaluate one’s landscape before making an irreversible decision. Trees are crucial for providing shade (i.e. energy savings), wildlife habitat, stormwater management, and maintaining property values.
Downed trees in a row along a hurricane-devastated street. Photo Credits: Mary Duryea, University of Florida
University of Florida researchers Mary Duryea and Eliana Kampf have done extensive studies on the effects of wind on trees and landscapes, and several important lessons stand out. Thanks also to Pam Brown, former Horticulture Agent from Pinellas County, for compiling many of these tips. Keep in mind that reducing storm damage often starts at the landscape design/planning stage!
- Select the right plant for the right place.
- Plant high-quality trees with central leaders and good structure. Branch attachment angles can affect weather a large branch will split from a tree. Wide-angle attachments are much more stable than narrow.
- Trees that have had regular structural preventive pruning are less likely to fail than neglected trees.
- Monitor pines carefully. Sometimes there is hidden damage and the tree declines over time. Look for signs of stress or poor health. Check closely for insects. Weakened pines may be more susceptible to beetles and diseases. Longleaf pine often survived storms in our area better than other species.
- Trees with decayed trunks are very dangerous in winds. Disease causing decay can come up from the roots or enter through improper pruning cuts. Remove hazard trees before the wind does. Have a certified arborist inspect your trees for signs of disease and decay. They are trained to advise you on tree health. To find a Certified Arborist go to: http://www.treesaregood.com/findtreeservices/FindTreeCareService.aspx
- Trees in a group (at least five) blow down less frequently than single trees.
- Trees should always be given ample room for roots to grow. Roots absorb nutrients, but they are also the anchors for the tree. If large trees are planted where there is limited or restricted area for roots to grow out in all directions, there is a likelihood that the tree may fall during high winds.
- Construction activities within about 20 feet from the trunk of existing trees can cause the tree to blow over more than a decade later.
- Plant a variety of species, ages and layers of trees and shrubs to maintain diversity in your community
- Post-hurricane studies in north Florida show that live oak, southern magnolia, sabal palms, and bald cypress stand up well compared to other trees during hurricanes. Pecan, water and laurel oaks, Carolina cherry laurel and sand pine were among the least wind resistant. For a full list of trees and their hurricane endurance, please visit http://edis.ifas.ufl.edu/pdffiles/FR/FR17300.pdf
- When a tree fails, plant a new one in its place.
