by Julie McConnell | Dec 4, 2020
Intense red fall color of Japanese Maple in Georgia is hard to replicate in our climate. J_McConnell, UF/IFAS
Fall is a favorite time of year for many people. Cool nights, short days, football games and the fast approaching holidays are all signs of summer coming to an end. Floridians who have relocated from other parts of the country may be disappointed to realize we get very little showy fall color even though we can grow some of the same trees in North Florida as other parts of the country. Why is that? Well, although plant breeders may promise “showy fall color” in certain selections, they really can’t promise that year after year because it’s more than just genetics influencing leaf color. Let’s take a deeper dive into the science behind fall color!
Why do the leaves change color?
Lower temperatures and shorter day length indicate to plants that winter is approaching and some physiological changes start to occur. Chlorophyll is a pigment found in leaves that, in addition to capturing sunlight and producing energy, also causes plants to display green during the growing season. As fall approaches, environmental changes tell plants to stop producing chlorophyll and existing pigment begins to break down. The reduction of chlorophyll allows the other pigments present (carotenoids and anthocyanin) to reveal their colors in an array of yellows, browns, oranges, reds, and purples. Different plants have different levels of these pigments and some may not exist at all in certain species. This explains why some plants typically turn only yellow and others may show yellow, orange, and/or red!
Why is there so much difference from year to year?
Variation occurs because environmental conditions and cultural practices play a part in determining how much color will be on display. Rainfall or irrigation amounts in the preceding summer and fall, drought cycles, nutrient levels, sunlight, and day and night temperatures all influence color from year to year.
How do I increase the potential for showy fall color in my landscape?
Choose plants with the reputation of producing desired fall colors in our area. However, keep in mind that because of the influence of outside conditions, you may be in for a surprise from year to year. To increase your chance of having a somewhat predictable fall display, use cultivars instead of seedlings of a plant species. A cultivar is a selection of a plant species that has been chosen for desirable traits, like growth habit, flowering, or fall color. These attributes are usually easily identified by the way their names are assigned. For example, Acer rubrum ‘October Glory’ is a red maple cultivar known for a full rounded canopy and exceptional red fall color. The reason that cultivars appear more consistent is because they are genetic copies of the parent plant that they are named for. A species or seedling plant is not a clone but comes from seed, which means you will get as much genetic variation as you see in human siblings. Just like children in our own families, each will each shine in their own way and no two will be exactly alike.
by Carrie Stevenson | Nov 18, 2020
The blackgum/tupelo tree begins changing leaf color in early fall. Photo credit: Carrie Stevenson, UF IFAS Extension
Florida isn’t necessarily known for its vibrant fall foliage, but if you know where to look this time of year, you can find some amazing scenery. In late fall, the river swamps can yield beautiful fall leaf color. The shades are unique to species, too, so if you like learning to identify trees this is one of the best times of the year for it. Many of our riparian (river floodplain) areas are dominated by a handful of tree species that thrive in the moist soil of wetlands. Along freshwater creeks and rivers, these tend to be bald cypress, blackgum/tupelo, and red maple. Sweet bay magnolia (Magnolia virginiana) is also common, but its leaves stay green, with a silver-gray underside visible in the wind.
The classic “swamp tree” shape of a cypress tree is due to its buttressed trunk, an adaptation to living in wet soils. Photo credit: Carrie Stevenson, UF IFAS Extension
Bald cypress (Taxodium distichum) is one of the rare conifers that loses its leaves. In the fall, cypress tress will turn a bright rust color, dropping all their needles and leaving a skeletal, upright trunk. Blackgum/tupelo (Nyssa sylvatica) trees have nondescript, almost oval shaped leaves that will turn yellow, orange, red, and even deep purple, then slowly drop to the swamp floor. Blackgums and cypress trees share a characteristic adaptation to living in and near the water—wide, buttressed trunks. This classic “swamp” shape is a way for the trees to stabilize in the mucky, wet soil and moving water. Cypresses have the additional root support of “knees,” structures that grow from the roots and above the water to pull in oxygen and provide even more support.
A red maple leaf displaying its incredible fall colors. Photo credit: Carrie Stevenson, UF IFAS Extension
The queen of native Florida fall foliage, however, is the red maple (Acer rubrum) . Recognizable by its palm-shaped leaves and bright red stem in the growing season, its fall color is remarkable. A blazing bright red, sometimes fading to pink, orange, or streaked yellow, these trees can jump out of the landscape from miles away. A common tree throughout the Appalachian mount range, it thrives in the wetter soils of Florida swamps.
To see these colors, there are numerous beautiful hiking, paddling, and camping locations nearby, particularly throughout Blackwater State Forest and the recreation areas of Eglin Air Force Base. But even if you’re not a hiker, the next time you drive across a bridge spanning a local creek or river, look downstream. I guarantee you’ll be able to see these three tree species in all their fall glory.
by Larry Williams | Oct 28, 2020
Nice fall crop of satsuma fruit. Photo credit: Larry Williams
When asked what kind of citrus to grow here in North Florida, my default response is satsuma. I usually get a funny look, followed by an attempt by the person who’s asking to repeat the name satsuma. The individual may ask, “What is satsuma… is that a citrus?” I guess the person expected to hear orange, grapefruit, lemon or maybe tangerine.
Satsuma is a type of citrus, technically classified as a mandarin and is sometimes referred to as satsuma mandarin. The satsuma mandarin is a good candidate for the North Florida citrus enthusiast for a number of reasons.
- Historically, mature dormant trees have survived minimum temperatures of 14°F to 18°F when budded/grafted to a cold-hardy rootstock such as trifoliate orange or swingle, a trifoliate orange cross. Young trees are not as cold-hardy but, due to their smaller size, are more easily covered with a cloth such as a sheet or lightweight blanket for protection during freezes.
- Satsuma fruit are ready to harvest October through December, ripening before the coldest winter temperatures. This is not true with most sweet citrus types such as oranges, which are harvested during winter months. Harvesting during winter works well in Central and South Florida where winters are mild but does not work well here in extreme North Florida. The potentially colder winter temperatures of North Florida are likely to result in the fruit on sweet oranges freezing on the tree before they are ripe, potentially ruining the fruit.
- Our cooler fall temperatures result in higher sugar content and sweeter fruit.
- Fruit are easily peeled by hand, have few to no seed and are sweet and juicy.
- Trees are self-fruitful, which means that only one tree is needed for fruit production. This is important where space is limited in a home landscape.
- Trees are relatively small at maturity, reaching a mature height of 15 to 20 feet with an equal spread.
- Branches are nearly thornless. This may not be true with shoots originating at or below the graft union. Shoots coming from the rootstock may have long stiff thorns. These shoots should be removed (pruned out) as they originate.
Satsuma fruit are harvested in fall but trees are best planted during springtime when temperatures are mild and as soil is warming. Availability of trees is normally better in spring, as well. For additional cold protection, purchase a satsuma grafted on trifoliate orange rootstock and plant the tree on the south or west side of a building. There are a number of cultivars from which to choose.
For more info on selecting and growing satsuma mandarin, contact the UF/IFAS Extension Office in your County or visit the following website.
https://edis.ifas.ufl.edu/ch116
by Carrie Stevenson | Oct 21, 2020
Even healthy live oaks need maintenance and occasional trimming to stay safe. Photo credit: Carrie Stevenson, UF IFAS Extension
After storms, Extension agents are routinely asked about whose responsibility it is to maintain a tree along a property line. This becomes particularly important in a situation where a property owner’s tree or branch falls and causes damage to their neighbor’s home or possessions.
To clarify this often contentious issue, reference to legal experts is necessary. In a series of publications called “The Handbook of Florida Fence and Property Law,” two attorneys and a University of Florida law student explain several statutes that give us direction. The section on “Trees and Landowner Responsibility” goes into further detail and cites case-law, but for ease of reading it is summarized below.
Situation 1: Removing a healthy tree on a shared property line.
If two neighbors share a tree on their property line and one of them wants to remove it, the adjoining landowner must give their permission. Removing trees can impact property value, heating/cooling bills, or aesthetic value. Without a neighbor’s consent, the landowner cutting down a tree can be legally liable for damages.
Hurricanes can have serious impacts on trees in their path. Photo credit: Carrie Stevenson, UF IFAS Extension
Situation 2: Responsibility for overhanging branches and roots.
A big storm hits your neighborhood, with tons of rain, wind, and lightning. You wake up in the morning and see that a large branch fell from your neighbor’s tree and crushed your kids’ basketball goal. If branches from the neighbor’s tree were otherwise healthy, they are not responsible for any damages resulting from the tree. If it was dead, however, and their negligence contributed to the branch falling, they will be responsible for damages.
Keep in mind that if the neighbor’s tree/branches/roots are in good health but interfering with something in your yard, you may trim them at your own expense. The same goes for your tree hanging in their yard, so while it’s not required, it’s always good to have a conversation first to let them know your plans.
After Hurricane Ivan, this tree’s root system completely uprooted and destroyed and adjacent fence. Photo credit: Beth Bolles, UF IFAS Extension
Situation 3: Hurricane Sally blew your neighbor’s tree over and into your yard.
Just like the situation with branches and roots, the same principle goes for an entire tree falling on adjoining property—if the tree was alive, it’s the responsibility of the person whose yard it fell in. If it was dead when it fell, it’s the responsibility of the tree’s owner to pay for damages.
In a complicated situation involving property damage, the saying, “good fences make good neighbors” only goes so far. Be sure to note the health of your trees throughout the year and trim back dead or dying branches. If you see serious decay or have concerns about a tree’s health, contact your county Extension office or a certified arborist. Finally, if the circumstances aren’t easily determined, be sure to contact a licensed attorney and/or your insurance company for direction.
by Beth Bolles | Oct 21, 2020
Many people often request a recommendation for a small tree that will be suitable for their landscape and one to consider is the Chinese Pistache, Pistachia chinensis. Although not a native tree, Chinese Pistache does not have invasive potential so it can make a suitable option for both commercial and residential landscapes.
Berries also offer nice fall color. Photo by Beth Bolles, UF IFAS Extension Escambia County
The best features of Chinese Pistache are the fall color it offers with orange leaves, followed by clusters of salmon berries. It will lose its leaves as days shorten but you can enjoy the textured bark during the winter season. Compound leaves offer interest as well during the spring and summer. Adding some medium to fine textured foliage plants under and around trees will provide a nice landscape display.
Chinese Pistache has been an attractive feature in the Escambia County Demonstration Garden for over 20 years. Photo by Beth Bolles, UF IFAS Extension Escambia County
A positive feature of Chinese Pistache is that once it is established, it is tolerant of drought. Expect trees to be about 25 to 30 feet in height with a 20 to 25 foot spread. Each tree will have it own unique branch structure and some pruning will be required when trees are young to develop strong connections. You may plant as a full sun tree to provide a little dappled shade for your garden or use as an understory tree in partial shade.
by Larry Williams | Oct 1, 2020
Adult cicada on tree branch, Photo credit: Lyle Buss, UF Entomologist
“What is that noise,” asked the visitors to Middle Georgia when I was a teenager. They were visiting during the summer from El Paso, Texas. I asked, “What noise?” The reply, “That loud noise in the trees.” I responded, “Oh, those are cicadas.’ There are sounds that are so common that sometimes you quit hearing them.
Before the visitors left for El Paso, I made sure to show them the brown, dry shells (exoskeletons) of cicadas that are not difficult to find attached to the trunk of a Georgia pine tree during summer. Cicadas leave their nymph exoskeletons on the trunks of trees and sometimes shrubs when they shed them to become mature flying adults.
You may not have ever seen a cicada but you’ve undoubtedly heard one if you live in Florida. These insects make a loud buzzing noise during the day in the spring and summer. Male cicadas produce their distinctive calls with drum-like structures called timbals, located on the sides of their abdomens. The sound is mainly a calling song to attract females for mating.
Cicadas spend most of their life underground as nymphs (immature insects) feeding on the sap of roots, including trees, grasses as well as other woody plants. They can live 10 or more years underground as nymphs. In some parts of the United States, there will be news reports of when periodical cicadas are expected to emerge from the ground. Periodical cicada species mature into adults in the same year, usually on 13- or 17-year life cycles. Their numbers can be enormous as they emerge, gaining much local attention. However, cicada species in Florida emerge every year from late spring through fall and in much smaller numbers as compared to the periodical cicadas.
Cicada emerging from exoskeleton, Photo credit: Lyle Buss, UF Entomologist
There are at least nineteen species of cicadas in Florida, ranging from less than a ¼ inch to over 2 inches in length. Some people might be frightened by their size and sounds but thankfully cicadas don’t sting or bite. They are a food source for wildlife, including some bird species and mammals.
Very rarely, I’ll have someone ask about small twigs from trees found on the ground as a result of the female cicada’s egg-laying process. But because this is usually such a minor issue with practically no permanent damage to any tree, cicadas really aren’t considered to be a pest of any significance in Florida.
For more information on cicadas, contact the University of Florida Extension Office in your County. Or visit the following UF/IFAS web page. https://edis.ifas.ufl.edu/in602
