by Carrie Stevenson | Sep 27, 2019
Ospreys, or fish hawks, build their nests from sticks atop dead trees. Photo credit: UF IFAS Extension
Big hurricanes like Dorian (Bahamas) and 2018’s Michael (central Florida Panhandle) were devastating to the communities they landed in. Flooding, wind, rain, loss of power and communications eventually made way for ad hoc clearing and cleanup, temporary shelters, and a slow walk to recovery. Among the most striking visual impacts of a hurricane are the tree losses, as there are unnatural openings in the canopy and light suddenly shines on areas that had been shaded for years. In northwest Florida, pines are particularly vulnerable. After any hurricane in the Panhandle, you can drive down Interstate 10 for miles and see endless pines blown to the ground or broken off at the top. During Hurricane Ivan 15 years ago, the coastal areas in Escambia and Santa Rosa lost thousands of trees not only due to wind, but also to tree roots inundated by saltwater for long periods.
Dead trees left by hurricanes serve as ideal nesting ground for large birds like ospreys. Photo credit: Carrie Stevenson, UF IFAS Extension
Nature always finds a way, though. Because of all those dead (but still-standing) pines, our osprey (Pandion haliaetus) population is in great shape in the Pensacola area. How are these two things related? Well, ospreys build large stick nests in the tall branches/crooks of dead trees, known as snags. They particularly prefer those near the water bodies where they fish. When I first moved here 20 years ago, I rarely saw ospreys. Now, it’s uncommon not to see them near the bayous and bays, or to hear their high-pitched calls as they swoop and dive for fish.
If you are not familiar with ospreys, they can be distinguished by their call and their size (up to six foot wingspan). It is common to see them in their large nests atop those snags, flying, or diving for fish. I usually see them with mullet in their talons, although they also prey on catfish, spotted trout, and other smaller species. They have white underbellies, brown backs, and are smaller than eagles but larger than your average hawk. One of their more interesting physical adaptations (and identifying characteristics) is their ability to grip fish parallel to their bodies, making it more aerodynamic than the perpendicular method most birds use.
Ospreys mate for life, and cooperate to build nests and care for young. The species has overcome many complex threats—including DDT damage to eggs and habitat loss—but the sight of them flying is always inspiring to me. They are a living embodiment of resilience amidst adversity.
by Sheila Dunning | Apr 18, 2019
Young Longleaf Pine
All of Florida’s ecosystems contain pine trees. There are seven native species in the state; Sand, Slash, Spruce, Shortleaf, Loblolly, Longleaf, and Pond. Each species grows best in its particular environment. Pines are highly important to wildlife habitats as food and shelter. Several species are equally valuable to Florida’s economy. Slash, Loblolly, and Longleaf are cultivated and managed to provide useful products such as paper, industrial chemicals, and lumber. All pines are evergreens, meaning they keep foliage year-round. The leaves emerge from the axil of each scale leaf into long slender needles clustered together in bundles. Needles are produced at the growing tips of each branch and remain on the tree for several years before turning reddish-brown and falling off. The bundles are referred to as “fascicles”. The length and number of needles in each fascicle is one way to help identify the different pine species.
A handy rule of thumb is that pines starting with “S” have needles in twos, while pines starting with “L” have needles in threes. And slash pine, which starts with “SL” has needles in twos and threes. The pond pine is also a three-needled fascicle. Pay attention to their length and the number that are held in a fascicle. Because the numbers per fascicle may vary, be sure to check several fascicles to get an overall sense for the plant! Longleaf has the longest needle, measuring over 10 inches. While sand pine has the shortest needles at around 2 inches in length. Pine cones are also a means for identification. Typically the longer the needle, the bigger the cone. But, they also vary in attachment and “spinyness’.
Cone of Loblolly Pine, attached directly to the stem
The outer (dorsal) surface of each seed cone scale has a diamond-shaped bulge, or “umbo,” formed by the first year’s growth. The umbo may or may not be armored with a “prickle,” a sharp point but not quite a spine or thorn, at the tip. As the seed cone continues to grow and expand, the exposed area at the end of each scale grows as well. The larger diamond-shaped area around the umbo, formed in the second year of growth, is called the “apophysis.” The shapes of the prickle, umbo, and apophysis can be helpful in identification. The male and female cones are separate structures, but both are present on the same plant. Pollen is produced by male cones and is carried by the wind to female cones where it fertilizes the ovules. Seeds develop and mature inside the female cones (also called the seed cones) for two years, protected by a series of tightly overlapping woody scales. Some pines open their seed cones after two years to release the seeds, while other pines continue to keep their cones tightly closed past maturity and release seeds in response to the heat of a forest fire.
To learn more about Florida’s pines and helpful hint on identification go to:
http://edis.ifas.ufl.edu/pdffiles/fr/fr00300.pdf
by Sheila Dunning | Jan 4, 2019
Tree planting in Mary Esther
The best time to plant a tree is twenty years ago. The second best time is for Arbor Day. Florida recognizes the event on the third Friday in January, but planting any time before spring will establish a tree quickly. Arbor Day is an annual observance that celebrates the role of trees in our lives and promotes tree planting and care. As a formal holiday, it was first observed on April 10, 1872 in the state of Nebraska. Today, every state and many countries join in the recognition of trees impact on people and the environment. Trees are the longest living organisms on the planet and one of the earth’s greatest natural resources. They keep our air supply clean, reduce noise pollution, improve water quality, help prevent erosion, provide food and building materials, create shade, and help make our landscapes look beautiful. A single tree produces approximately 260 pounds of oxygen per year. That means two mature trees can supply enough oxygen annually to support a family of four. The idea for Arbor Day in the U.S. began with Julius Sterling Morton. In 1854 he moved from Detroit to the area that is now the state of Nebraska. J. Sterling Morton was a journalist and nature lover who noticed that there were virtually no trees in Nebraska. He wrote and spoke about environmental stewardship and encouraged everyone to plant trees. Morton emphasized that trees were needed to act as windbreaks, to stabilize the soil, to provide shade, as well as, fuel and building materials for the early pioneers to prosper in the developing state. In 1872, The State Board of Agriculture accepted a resolution by J. Sterling Morton “to set aside one day to plant trees, both forest and fruit.” On April 10, 1872 one million trees were planted in Nebraska in honor of the first Arbor Day. Shortly after the 1872 observance, several other states passed legislation to observe Arbor Day. By 1920, 45 states and territories celebrated Arbor Day. Richard Nixon proclaimed the last Friday in April as National Arbor Day during his presidency in 1970. Today, all 50 states in the U.S. have official Arbor Day, usually at a time of year that has the correct climatological conditions for planting trees. For Florida, the ideal tree planting time is January, so Florida’s Arbor Day is celebrated on the third Friday of the month. Similar events are observed throughout the world. In Israel it is the Tu B Shevat (New Year for Trees). Germany has Tag des Baumes. Japan and Korea celebrate an entire week in April. Even, Iceland one of the most treeless countries in the world observes Student’s Afforestation Day. The trees planted on Arbor Day show a concern for future generations. The simple act of planting a tree represents a belief that the tree will grow and some day provide wood products, wildlife habitat erosion control, shelter from wind and sun, beauty, and inspiration for ourselves and our children.
Trees provide us with benefits including serving as a sound barrier, stormwater abatement, and of course fresh air and oxygen
“It is well that you should celebrate your Arbor Day thoughtfully, for within your lifetime the nation’s need of trees will become serious. We of an older generation can get along with what we have, though with growing hardship; but in your full manhood and womanhood you will want what nature once so bountifully supplied and man so thoughtlessly destroyed; and because of that want you will reproach us, not for what we have used, but for what we have wasted.”
~Theodore Roosevelt, 1907 Arbor Day Message
by Sheila Dunning | Dec 19, 2018
Throughout history the evergreen tree has been a symbol of life. “Not only green when summer’s here, but also when it’s cold and dreary” as the Christmas carol “O Tannenbaum” says. After such devastating tree losses in the Panhandle this year, this winter is a prime time for installing more native evergreens.
While supporting the cut Christmas tree industry does create jobs and puts money into local economics, every few years considering adding to the urban forest by purchasing a living tree. Native evergreen trees such as Redcedar make a nice Christmas tree that can be planted following the holidays. The dense growth and attractive foliage make Redcedar a favorite for windbreaks, screens and wildlife cover. The heavy berry production provides a favorite food source for migrating Cedar Waxwing birds. Its high salt-tolerance makes it ideal for coastal locations. Their natural pyramidal-shape creates the traditional Christmas tree form, but can be easily pruned as a street tree.
Two species, Juniperus virginiana and Juniperus silicicola are native to Northwest Florida. Many botanists do not separate the two, but as they mature, Juniperus silicicola takes on a softer, more informal look. For those interested in creating a different look, maybe a Holly (Ilex,sp.) or Magnolia with full-to-the-ground branches could be your Christmas tree.
When planning for using a live Christmas tree there are a few things to consider. The tree needs sunlight, so restrict its inside time to less than a week. Make sure there is a catch basin for water under the tree, but never allow water to remain in the tray and don’t add fertilizer. Locate your tree in the coolest part of the room and away from heating ducts and fireplaces. After Christmas, install the new tree in an open, sunny part of the yard. After a few years you will be able to admire the living fence with all the wonderful memories of many years of holiday celebrations. Don’t forget to watch for the Cedar Waxwings in the Redcedar.
by Sheila Dunning | Nov 9, 2018
As the trees begin to turn various shades of red, many people begin to inquire about the Popcorn trees. While their autumn coloration is one of the reasons they were introduced to the Florida environment, it took years for us to realize what a menace Popcorn trees have become. Triadica sebifera, the Chinese tallowtree or Popcorn tree, was introduced to Charleston, South Carolina in the late 1700s for oil production and use in making candles, earning it another common name, the Candleberry tree. Since then, it has spread to every coastal state from North Carolina to Texas, and inland to Arkansas. In Florida it occurs as far south as Tampa. It is most likely to spread to wildlands adjacent to or downstream from areas landscaped with Triadica sebifera, displacing other native plant species in those habitats. Therefore, Chinese tallowtree was listed as a noxious weed by the Florida Department of Agriculture and Consumer Services Noxious Weed List (5b-57.007 FAC) in 1998, which means that possession with the intent to sell, transport, or plant is illegal in the state of Florida. The common name of Florida Aspen is sometimes used to market Popcorn tree in mail-order ads. Remember it’s still the same plant.
Although Florida is not known for the brilliant fall color enjoyed by other northern and western states, we do have a number of trees that provide some fall color for our North Florida landscapes. Red maple, Acer rubrum, provides brilliant red, orange and sometimes yellow leaves. The native Florida maple, Acer floridum, displays a combination of bright yellow and orange color during fall. And there are many Trident and Japanese maples that provide striking fall color. Another excellent native tree is Blackgum, Nyssa sylvatica. This tree is a little slow in its growth rate but can eventually grow to seventy-five feet in height. It provides the earliest show of red to deep purple fall foliage. Others include Persimmon, Diospyros virginiana, Sumac, Rhus spp. and Sweetgum, Liquidambar styraciflua. In cultivated trees that pose no threat to native ecosystems, Crape myrtle, Lagerstroemia spp. offers varying degrees of orange, red and yellow in its leaves before they fall. There are many cultivars – some that grow several feet to others that reach nearly thirty feet in height. Also, Chinese pistache, Pistacia chinensis, can deliver a brilliant orange display.
Young Trident maple with fall foliage. Photo credit: Larry Williams
There are a number of dependable oaks for fall color, too. Shumardi, Southern Red and Turkey are a few to consider. These oaks have dark green deeply lobed leaves during summer turning vivid red to orange in fall. Turkey oak holds onto its leaves all winter as they turn to brown and are pushed off by new spring growth. Our native Yellow poplar, Liriodendron tulipifera, and hickories, Carya spp., provide bright yellow fall foliage. And it’s difficult to find a more crisp yellow than fallen Ginkgo, Ginkgo biloba, leaves. These trees represent just a few choices for fall color. Including one or several of these trees in your landscape, rather than allowing the Popcorn trees to grow, will enhance the season while protecting the ecosystem from invasive plant pests.
For more information on Chinese tallowtree, removal techniques and native alternative trees go to: http://edis.ifas.ufl.edu/ag148.
by Les Harrison | Oct 26, 2018
Only a shell of its former self, the exoskeleton shed by a cicada is all that remains of the previous night’s long pursuits.
Autumn evenings in the panhandle are usually beginning to reflect the official change of seasons with cooler air and a slight lessening of the raucous din created by insects and birds. The recent early-fall hurricanes have brought the area a wide breath of hot, humid air, delaying the long anticipated start of relief from the sultry summer environment.
Anyone hearty enough to take an early evening walk in north Florida will experience a continuation of the frenetic activity and riotous sounds typical to summer in the south. The near deafening call of cicadas (Magicicada spp.) is part of the cacophony.
Once commonly identified as locust in the region, their near-mechanical buzzing originates from the protection of foliage in trees and bushes during the day or twilight hours. During the dark hours they sing often and relocate frequently.
It is important to note cicadas are not the locust of infamy which shred the green, lush landscapes and foretells famine. While locust and cicadas are both insects, the similarities end there.
These seldom seen or captured insects known for their boisterous, sometimes undulating, chorus do leave strategically placed souvenirs for the sharp-eyed observer. This discarded residue of their early life stages is a highly valued tool for many elementary school boys with a prank in mind. The hard shell is harmless, but under the right conditions does have a certain shock value appreciated by juvenile miscreants.
Their nymph stage skeletons are often seen on the trunks of trees, shrubs stalks and even the siding of buildings. The opaque brown shells are abandoned when the cicada outgrows it and then emerges to form a new exterior.
The process is similar in other insect species with an exoskeleton having very limited potential for growth and expansion. The rigid coating provides this creature an armored surface to fend off the challenges of being small and small in a big hungry world.
In some states, cicadas are famous for their periodic appearance in colossal numbers, sometimes as many as 1.5 million per acre. These once every 13 to 17 year swarms do not occur in Florida which has an insect friendly environment.
The 19 Florida cicada species fall into three groups based on overall size measured by the length of the forewings. They produce their songs with timbals, paired drum-like structures on the sides of the abdominal segments.
A muscle attached to the timbal plate causes the timbal ribs to pop inward and project outward when relaxed. Flexed rapidly, the cicada chorus can deliver hours of uninterrupted night music.
In Florida, only males have timbals and the females are mute. Most sounds made by males are calling songs which serve to attract the silent females.
Cicada nymphs live in underground burrows where they feed on xylem sap from roots of grasses or woody plants. Because xylem sap is low in nutrients, complete nymph development takes several years to successfully mature.
All cicada species molt four times underground. When the cicada nymph is ready for its fifth and final molt it makes its way to the soil’s surface. It climbs a short distance up a tree trunk or stem, anchors itself and molts for the last time becoming an adult.
If male, the new cicada will add its contribution to the nightly festivities. If female, she will quietly wait for that special, one in a million, nocturnal crooner.
To learn more about north Florida’s noisy night insects, contact the local UF/IFAS County Extension Office. Click here for contact information.
