Chickasaw Plum

Chickasaw Plum

The Chickasaw plum is covered in beautiful small white flowers in the spring. Photo credit: UF IFAS

The native Chickasaw plum is a beautiful smaller tree (12-20 ft mature height) that is perfect for front yards, small areas, and streetscapes. True to its name, the Chickasaw plum was historically an important food source to Native American tribes in the southeast, who cultivated the trees in settlements well before the arrival of Europeans. They typically harvested and then dried the fruit to preserve it. Botanist-explorer William Bartram noted the species during his travels through the southeast in the 1700’s. He rarely saw it in the forests, and hypothesized that it was brought over from west of the Mississippi River.

Humans and wildlife find Chickasaw plums delicious. Photo credit: UF IFAS

One of the first trees to bloom each spring, the Chickasaw plum’s white, fragrant flowers and delicious red fruit make it charmingly aesthetic and appealing to humans and wildlife alike. The plums taste great eaten fresh from the tree but can be processed into jelly or wine. Chickasaw plums serve as host plants for the red spotted purple butterfly and their fruit make them popular with other wildlife. These trees are fast growers and typically multi-trunked.

Almost any landscape works for the Chickasaw plum, as it can grow in full sun, partial sun, or partial shade, and tolerates a wide variety of soil types. The species is very drought tolerant and performs well in sandy soils.

The plum is in the rose family and has thorns, so it is wise to be aware of these if young children might play near the tree.

Winter is ideal tree-planting time in Florida. While national Arbor Day is in spring, Florida’s Arbor Day is the 3rd Friday of January due to our milder winters.

For more information about tree selection in northwest Florida, contact your local county Extension office.

American beautyberry

American beautyberry

When beautyberries start producing their eye-catching, bright purple fruit in late summer, we start to get lots of questions. People want to know what it is, where can they find it, and can they eat it? While the berries look good enough to eat, it’s best to leave them to the birds and deer. They are not toxic and were used by Native Americans for a root tea to treat fevers, stomach aches, malaria, and more, but the taste has been described as bitter and mealy. Thanks to a generous volunteer, I am lucky enough to have tried beautyberry jelly. A little (or a lot) of sugar can make most anything taste good—and the finished product is a beautiful, translucent shade of fuchsia.

Homemade beautyberry jelly is a real treat for breakfast! Photo credit: Carrie Stevenson, UF IFAS Extension

Even more interesting to me was the revelation that researchers have been able to extract compounds from beautyberry that successfully repel pest insects such as ticks and mosquitoes. The study began about 15 years ago, after a Mississippi botanist with the USDA Agricultural Research Service mentioned to a colleague that his grandfather taught him to rub the crushed leaves of beautyberry on his skin. The technique had been used as a home remedy to prevent mosquito bites for people (and horses) for generations. As a follow up experiment, another group of researchers found these same compounds—callicarpenal and intermedeol—successfully repelled black-legged ticks (which transmit Lyme disease) as effectively as DEET. In the last few years, researchers out of Mississippi have worked towards creating natural insect repellents from the compound that are less harsh on human skin that many commercially available brands.

The striking purple berries of the beautyberry shrub attract the attention of people and wildlife, alike. Photo credit: Carrie Stevenson, UF IFAS Extension

Aside from its many practical uses, Callicarpa americana is a beautiful native shrub. It has wide green leaves and the brilliant purple berries grow in clusters along its stem. They stay on through late fall and winter in some places, making a beautiful contrast to fall foliage. Beautyberry shrubs can be found in a wide variety of habitats, including sandy and wet soils, full sun, and part shade. Their adaptability makes them a great plant for tight conditions like roadsides or yard edges, but also for nearly any home landscape. The plants can grow to a height of 4-8 feet and spread 3-6 feet wide. The long-lasting berries make them a great wildlife food source later in the cool season than many berry-producing species.

Mole Crickets

Mole Crickets

A mole cricket has a face only a mother could love. They are so strange looking, in fact, that in the past week I’ve had two people ask me what they were. They have large, round, helmet-like heads, undersized eyes, and massive front claws used for digging. Unlike your garden-variety crickets, which really don’t cause any major damage to home landscapes, the mole cricket is quite the turfgrass menace. Instead of hopping about aboveground, they tunnel beneath the lawn and feast on the roots and leaves of grass, often destroying entire yards. They are also vegetable pests, going after tomatoes, cabbage, and peppers.

A young mole cricket. Its round head and large front claws distinguish it from other cricket species. Photo credit: Lucy Adams Stevenson
A) Horizontal and B) vertical view of a generalized tawny mole cricket burrow showing
1) horn, 2) 1st constriction, 3) bulb, 4) 2nd constriction, 5) turn-around,
6) surface tunnel, and 7) deep tunnel. Figure 1 from Nickerson et al. 1979. Ann. Entomol. Soc. Am. 72(3):438-440.

Mole crickets spend most of their time below ground and form burrows for hiding, laying eggs, and traversing through their territory. In mating season, males create a monotone song that averages 88 decibels—as loud as a motorcycle! The call comes from their burrows, which have funnel-like openings that expand at the surface, creating amplification comparable to a horn.

Beneficial larra wasp parasitizing a tawny mole cricket. Photo credit: UF IFAS

The tawny mole cricket (Neoscapteriscus vicinus) is the most common to our area and is an invasive species from South America. UF IFAS has had a specific research program related to mole cricket management since the late 1970’s. One successful outcome of this program has been the introduction of a biological control species, the larra wasp (Larra bicolor). The wasp manages mole cricket populations by stinging and temporarily paralyzing crickets. A female will then deposit an egg into the mole cricket’s body. The cricket recovers and goes about its daily routine until the egg hatches, at which point the larval wasp feeds on and eventually kills the mole cricket. Along with the wasp and release of flies and a nematode that also manage mole crickets, the biocontrol methods introduced between the 1980’s and 2004 have resulted in a 95% reduction in mole cricket populations in north Florida.

If you are seeing mole crickets, you can attract larra wasps to your property by planting shrubby false buttonweed or partridge pea plants, which the wasps feed on. If you have serious damage from mole crickets, check out this thorough Mole Cricket Integrated Pest Management Guide, or contact the horticulture agent at your local county extension office to get a site-specific recommendation for management.

Selecting Wind-Resistant Trees for Hurricane Season

Selecting Wind-Resistant Trees for Hurricane Season

The Pensacola area has had its fair share of rough weather lately. While the recent storms were not hurricanes, the rainfall totals rivaled many tropical storms, and the lighting and wind were disastrous. A tornado caused significant damage, including a tragic death, with more tumultuous weather in the forecast. Our rainy hurricane season has just begun, so it is worth talking about tree selection, management, and preparing for storms.

After the busy 1992, 1995, 1998, and 2004-05 hurricane seasons, several University of Florida researchers undertook an exhaustive on-the-ground project to look at tree damage statewide. Their goal was to determine which species survived high winds, and which trees were the most vulnerable during storms. Their findings were consistent, and have held up over the past few decades. A full description of the project can be found online, along with several publications that go over proper pruning and maintenance of trees, both before a storm and after recovery.

Live oaks have dense wood and are extremely wind-resistant species. Photo credit: Carrie Stevenson, UF IFAS Extension

For the “coastal plain” of north Florida, the most wind-resistant species are: live and sand live oaks (Quercus virginiana/Q. geminata), American holly (Ilex opaca), Sabal palm (Sabal palmetto), Southern magnolia (Magnolia grandiflora), bald cypress (Taxodium distichum), Florida scrub hickory (Carya floridana), dogwood (Cornus florida), sweet gum (Liquidambar styraciflua), and crape myrtle (Lagerstroemia indica). The live oaks and sweet gums do have a tendency to lose branches, so it is important to undertake proper pruning in the off season to trim up potential problem limbs.

This chart developed by UF researchers denotes the percentage of trees surviving Hurricane Ivan, by species.
Courtesy M. Duryea and E. Kampf

Live oaks, and sand live oaks (which live on coastal sand dunes) are slow-growing trees with extraordinarily dense wood. This protects them in hurricane-force winds. Part of the working theory on why bald cypress, holly, and magnolia do well in storms is their pyramidal shape, which seems to allow wind to whip circularly around the trees and avoid damage. Sabal palms are botanically considered part of the grass category and not trees, so their single, flexible trunk allows them to handle the onslaught of wind. Sweetgums are particularly hardy in tornadoes, due to their sturdy root system and shorter, “stout” branches. Smaller understory trees like crape myrtle and dogwood are likely dodging the strongest winds, but also have strong branch structures and dense wood. These two species, along with sand live oak, also lost an average of more than 80% of their leaves. This defoliation is an adaptation to heavy winds, with trees that lost leaves performing better overall than species that held onto their leaves but toppled at the trunk.

The least wind resistant species, according to the studies, included: sand pine (Pinus clausa), loblolly pine (Pinus taeda), and spruce pines (Pinus glabra)laurel and water oaks (Quercus laurifolia/Q. nigra), Southern red oak (Quercus falcata), Southern red cedar  (Juniperus silicicola), Carolina laurelcherry (Prunus caroliniana), black cherry (Prunus serotina), Loquat (Eriobotrya japonica), pecan (Carya illinoensis), sycamore (Platanus occidentalis), tulip poplar (Liriodendron tulipifera), Bradford pear (Pyrus calleryana), and red maple (Acer rubrum). A couple of pine species—slash and longleaf—performed in the medium range. In my experience post-hurricane, many of these trees that survived were stressed and ended up with pine bark beetle infestations. Water and laurel oak are common trees in Florida home landscapes, but typically have much shorter lifespans than live oaks. They are faster growing but have weaker wood, and are vulnerable to storms.

Significant damage to a home after a tornado struck Pensacola in 2016. Photo credit: Carrie Stevenson, UF IFAS Extension

Another list of tree survivability was developed for residents in tropical and subtropical regions of the state. If you have friends or family in south-central Florida, be sure to share this information with them.

Besides planting wind-resistant species, the research team shared other observations related to tree planting and arrangement, too. Single trees are more vulnerable than trees planted in clusters, as they protect each other from incoming winds. Older trees, and those with preexisting damage, are more likely to fall. Trees with plenty of space around their roots do better—if a tree is surrounded on two or more sides with buildings or other hard surfaces, they cannot spread adequately. Detailed information on identifying damaged or poorly structured trees, along with maintenance and pruning tips, can be found in the “Urban Forest Hurricane Recovery Program” series of articles written by the UF tree specialists involved in the studies. The publications include good diagrams and photos of specific examples.

Sandhill Milkweed – Attracting Butterflies in the Dunes

Sandhill Milkweed – Attracting Butterflies in the Dunes

Like finding buried treasure on a desert island, walking up on a mound of sandhill milkweed (Asclepias humistrata) may elicit cries of excitement from someone who understands what they’re seeing. And not unlike searching for pirate booty, there’s a bit of danger involved, too—milkweed is highly toxic.

The eye-catching pink coloration of the leaves, stems, and complex flowers make this variety of milkweed stand out among the dunes. Photo credit: Carrie Stevenson, UF IFAS Extension

Last month in the dunes of Perdido Key, our Master Naturalist class found robust clusters of eye-catching, pink-tinged leaves, blooms, and buds of sandhill milkweed. Also known as pinewoods milkweed, this variety thrives in dry, sandy soils. It is native to the southeast, found typically in the wilds of Alabama, Mississippi, Louisiana, Georgia, Florida, South Carolina, and North Carolina. Its genus name, “Asclepias” refers to the Greek god of healing—indigenous people have used the plant for medicinal purposes (dysentery treatment and wart removal, in particular) for centuries. The species name humistrata means “spreading,” which describes the growth habit of the plant. Milkweed is highly toxic, so we do not recommend trying any medicinal uses at home! The “milk” part of the common name refers to its sap, which is a thick, sticky, white substance containing that toxic chemical.

The seedpods of sandhill milkweed are large and full of seeds with wispy fibers that allow them to float through the air for dispersal. Photo credit: Gabriel Campbell, UF/IFAS

As the only food source for the monarch caterpillar, healthy milkweed plants are crucial for maintaining populations of the famous monarch butterfly.  The plant itself is rather complex and beautiful. Its five-petaled blooms grow in tight clusters, on stalks sticking several inches off the ground. The leaves are broad and a deep forest green, edged in the pale maroon/pink of the stems and flowers. The seedpods of milkweed are quite large (3-6” long), resembling pea pods and full of seeds. Each seed has a wispy white fiber attached, which helps it disperse in the wind like a dandelion. The fibers have been used for years as stuffing for pillows and mattresses, and were used for life jackets during World War 2.

Numerous monarch caterpillars feed on a sandhill milkweed plant. Photo credit: Carrie Stevenson, UF IFAS Extension

The first cluster of milkweed we found was host to multiple monarch caterpillars, recognizable by their greenish-yellow, white, and black stripes. By the time you see caterpillars, the milkweed is already working its magic, transferring its toxins to the insects but causing them no harm. Monarchs have evolved the capability to digest and metabolize this poison, which would induce heart attacks in nearly any vertebrate animal.  Adult monarchs use several nectar sources, including milkweed flowers, and females lay their eggs on the plant so that their young can begin eating once hatched.

In the animal kingdom, red and orange are signs of danger.  The bright orange coloration of an adult monarch butterfly serves as a warning to would-be predators to exhibit caution, as the toxins from their food sources stay within the butterfly’s body. The copycat viceroy, soldier, queen, and Gulf fritillary butterflies benefit from this trait by using mimicry in their own orange coloration to ward off predators.