The telltale intense growth of a witches’ broom in a pine tree. Photo credit: Keith LeFevre
Our topic today might seem better suited to late October, but it can be observed in the woods year-round. During a recent Master Naturalist class, we discussed the various species of pines that grow in northwest Florida. All seven Florida native species—longleaf, loblolly, pond, slash, shortleaf, sand, and spruce—grow in our area of the state. While they can be differentiated based on growing location, needle length, and growth pattern, one of our class members had seen something really bizarre in the local pines.
A witches’ broom in this spruce tree has resulted in a miniature version growing along its primary trunk. Photo credit: American Conifer Society
What he described was essentially an intense burst of pine needle growth at the tip of a branch. It stands out as deep green, dense, and unusual among the regular growth pattern of needles. The end result is essentially the production of a “mini-me,” a miniature copy of the normally growing tree, hanging off one of the branches. That afternoon while touring Blackwater River State Forest with a professional forester, we asked him about the strange phenomenon. He’d seen it many times and referred to it as a “witches’ broom.”
Mistletoe growing in a tree results from the same type of auxin disturbance as witches’ brooms. Photo credit: Carrie Stevenson, UF IFAS Extension
In normal tree growth, the trunk produces hormones called auxins, which control the division, expansion, and differentiation of cells. The hormones are concentrated in the growing tips of roots and shoots, and auxins maintain normal growth and keep smaller branches from overtaking the “leader.” Unusual growth occurs when the presence and concentration level of auxin is interfered with by an outside factor. The intense growth seen in these affected trees may be triggered in several ways, including pest, fungus, or mistletoe infestation, or death of terminal buds by environmental conditions. Phytoplasmas—bacteria that infect the phloem tissues—transferred by insect vectors (usually leafhoppers) are also blamed for the odd growth in some plants. Pines aren’t the only species affected; witches’ brooms can be found in other conifers like firs and junipers, nut species like hickory, pecan, and walnut, or in ashes, peaches, and elms.
The prolific growth of witches’ brooms is of great interest to horticulturists hoping to propagate dwarf varieties of the trees. This post by the American Conifer Society goes into great detail on how to “hunt”, cultivate, and encourage the growth of witches’ brooms into dwarf plants for the home landscape. Ecologically, witches’ brooms are not a huge problem for their host trees. Unless vulnerable to a massive outbreak of parasitic mistletoe, trees usually continue growing around them and live normal lifespans. The dense brush can even benefit wildlife, becoming a ready-made nest for birds or tree-dwelling mammals.
Kitchen and yard waste can be recycled into excellent soil amendments, reducing waste and saving money. Photo credit: UF IFAS Extension
When we turn the page into a new year, the motto is often “out with the old, in with the new.” But what if we actually kept the old and transformed it into something really useful? That’s exactly what happens with composting. Instead of raking up leaves, bagging them, and throwing them away, you can recycle them in a compost bin. The same goes for food waste—instead of throwing it in the trash, a significant percentage of our groceries can be repurposed. These in-house materials can produce your own high-quality potting soil and mulch, for free.
Compost bins should be located in an unobtrusive but convenient location. Photo credit: Carrie Stevenson, UF IFAS Extension
So, where to start? Logistics are important. If a compost bin is inconvenient, you won’t use it. Locate bins in a regularly traversed part of your yard, so it’s easier to make dropping the kitchen waste into a bin part of your routine. If you’ve got space, you can use a counter-top compost container or just a second trash can to hold material until it goes outside. Compost bins should be fairly close to a water source in case you need to moisten the material.
The composting demonstration area at our Extension office includes several types of bins. Photo credit: Carrie Stevenson, UF IFAS Extension
There are numerous types of bins, ranging from open-topped 3-sided wooden or concrete block piles, to hand-built bins with adjustable slats, or prefabricated plastic and metal bins and turners. If you have a lot of space, the open holding areas might work fine. But, in a neighborhood you may want a neater, more contained and covered bin.
Properly layered compost. Figure courtesy of Colorado State University Extension
The ingredients for compost are simple—you need “greens” and “browns”. “Greens” include fresh vegetables, fruit, eggshells, coffee grounds, lawn clippings, and other materials that contain nitrogen. These should be raw waste—if they’ve been cooked in oil or butter, they can go rancid in the pile, causing an odor and attracting unwanted wildlife. “Browns“ are carbon-rich materials that include dry leaves, straw, pine needles, and shredded uncolored paper. Besides oils, you’ll want to avoid meat and dairy products, dog/cat waste, and plants full of weedy seeds or recently treated with pesticides.
Finished compost can be used as a soil amendment or potting soil. Photo credit: IFAS Photography
This mix of green and brown materials provides a balance of carbon and nitrogen. You’ll layer the materials, green/brown/green/brown and add a bit of water. Once the compost starts “cooking,” microorganisms from the surrounding soil will start further breaking down the larger materials. These are the critters who put the decomposition in compost. Worms will often make their way in, adding their efforts to the material breakdown. There is a much more specific process of vermiculture (aka worm farming) if your primary interest is producing worms. Compost can take as long as you want it to—in the hot, humid Florida summers, with regular mixing you can produce compost from raw materials in as little as 2 months. In cooler weather or in passive composting, where you just dump it and leave it alone—it will take longer. Properly managed compost will not smell bad, so if there is an odor, add more “browns” or mix it. Ideas for troubleshooting compost bins can be found in Table 3 of the UF publication, “Compost Tips for the Home Gardener.”
For more information and great detail on both composting and vermiculture, check out the recorded webinar on YouTube our horticulture team hosted in October.
The Borneo camphor tree (Dryobalanops aromatica) exhibits a perfect example of crown shyness. Photo from Wikimedia commons at the Kuala Lumpur Research Forest
I spent a lot of time in my childhood lying in our backyard hammock, reading. Inevitably, I’d take a break and stare up at the tree canopy above me. We had sweetgum trees in that corner of our yard, and I’d watch squirrels chasing each other through the branches. One thing I noticed, but never really investigated, was how the highest branches spread out towards each other from the clump of trees, yet didn’t touch or overlap each other. You could nearly always see gaps of sunlight outlining the individual trees.
The canopy of mature oak trees exhibiting crown shyness. Photo credit: Carrie Stevenson, UF IFAS Extension
The term for this is “crown shyness.” As anthropomorphized as that seems, it’s an apt description for this seemingly polite growth pattern. The topmost branches of any given tree are in constant competition with each other for sunlight. Being photosynthesizers, sunlight is life. No growth can happen without the basic ingredients of sunlight, water, and carbon dioxide. So, from a tree’s perspective, there is an inherent disincentive to send growth beneath their own existing branches or those of an adjacent tree. The result of this is a botanical dance of sending branches out, neighboring trees doing the same, and multiple trees subtly angling for light. It’s like sharing an armrest on an airplane with a stranger. There’s a limited and highly desirable resource (the armrest), resulting in a (hopefully) gentle back and forth where someone either claims the space fully or you make an unspoken agreement to share it. If you do share it, it’s rare your arms touch; most of us want to keep some personal space!
Like Blue Angel jets in the diamond formation, trees will keep just a bit of sunlight between them and their neighbor. Photographed by Mass Communication Specialist 1st Class Ian Cotter. Official U.S. Navy Photograph.
While we may consciously shuffle for position in crowded public spaces, this happens for trees at a metabolic level. Evidence from an Argentinian study demonstrated that trees can “detect the presence of neighbors before being shaded by them,” using an internal sensor that detects light on the red:far red spectrum. This botanical spidey-sense comes from light-receptor proteins called phytochromes, which send out an alert that they’re close to another tree and may want to stop sending branches that direction. Growing into an adjacent tree quickly brings diminishing returns for absorbing sunlight, and it is in the tree’s best interest to keep a safe distance.
Single-species stands of pine trees exhibit crown shyness. Photo credit: Tyler Jones, UF IFAS
Crown shyness appears to be more pronounced in groves of same-species trees. Monocultures like pine plantations, or even large stands of black mangrove, exhibit the same growth patterns and timing, adapting to environmental factors the same way—particularly if they were planted or germinated at the same time. Foresters or ecologists trying to maximize the space for timber, fruit, or ecosystem restoration may want to deliberately encourage a diverse array of species, which fill in the gaps beneath the canopy and survive on less direct sunlight.
Maybe we could call it “crowd” shyness when people step back to give folks room to dance, avoiding “mechanical abrasion”! Photo credit: Cole Stevenson, University of the South
Another contributing factor to crown shyness, and perhaps one of the more crucial ones, is “mechanical abrasion.” University of Florida botanist Francis “Jack” Putz conducted research on this in Costa Rica back in the 80’s, which is still frequently cited in more recent publications. His team’s findings showed that crown shyness was “positively correlated with the distance pairs of trees adjacent to the gap swayed in the wind.” When tree branches physically bumped into one another on a regular basis, they kept their distance to prevent bud, bloom, and branch tip damage. For this scenario, imagine someone dancing enthusiastically in the middle of a big music festival—if there’s room, people will often spread out. The more the person flails, the more space you give them. If they’re just minimally swaying back and forth, you might stand closer. Putz, et. al observed this same principle in the coastal mangrove forests—more flexible branches adjacent to one another gave each other more space, while those with “stiff crowns” that couldn’t move much grew closer together.
When space opens up due to the loss of a neighboring tree or branch, the infusion of sunlight/fuel spurs a tree to send energy quickly to gain the advantage over adjacent trees. Tree species vary in their capability and success in doing this. An earlier article on pioneer species (the first to occupy a newly open space) and the process of succession sheds more light on this natural phenomenon. In a mature forest, the end result is a balanced mosaic of tree branches reaching out and nearly touching one another, but leaving each other space to grow.
A large Carolina wolfberry shrub thrives near St. Marks’ lighthouse at the wildlife refuge. Photo credit: Carrie Stevenson, UF IFAS Extension
I was lucky enough to spend a weekend in November exploring a lovely, low-key stretch of northwest Florida. We hiked trails and took the boat tour at Wakulla Springs State Park, marveling at the numerous alligators and admiring birds and a slow-moving manatee. We also hiked through St. Marks National Wildlife Refuge, which is home to a nearly 200-year-old lighthouse and keeper’s house, which have a fascinating history of their own.
The brilliant red, and edible, berry of the Carolina wolfberry is ripe in late fall/early December. Photo credit: Carrie Stevenson, UF IFAS Extension
Exploring the shoreline of Apalachee Bay behind the lighthouse, we watched fiddler crabs run the salt flats and herons quietly stalk their prey. Always on the lookout for something new, I noticed a large shrub growing several yards back from the beach. It looked like a cross between a rosemary and a holly, with delicate lavender/purple flowers and brilliant red teardrop-shaped fruit. I’d never seen it before.
Map of the natural range of Carolina wolfberry in Florida. Figure courtesy of the Florida Native Plant Society.
After a quick investigation, I learned it was a Carolina wolfberry, aka Carolina deserthorn, aka Christmas berry (Lycium carolinianum). The invasive species coral ardisia (Ardisia crenata) is also known in some areas as Christmas berry—this is why scientific names are so useful—but that is not the plant we saw at St. Marks. The native Carolina wolfberry was located right where you might expect it, on dry coastal scrub, in view of the saltwater it easily tolerates. Its native range in Florida starts along the coastline east of here, particularly Bay and Wakulla counties and all the way down around the state.
The delicate lavender flower of the Carolina wolfberry is a popular nectar source for native butterflies. Photo credit: Peggy Romfh
The tall shrub is evergreen, with leaves adapted into a long, thin, slightly succulent near-needle shape. This leaf form helps hold water in a dry, salty environment and prevents evaporation. The tips of the shrub’s branches have thorns, hence the common name “desert-thorn.” Carolina wolfberry produces those attractive little purple blooms in the fall, providing nectar for several species of native butterflies. In late fall/early winter, the brilliant red fruits show up. They are less than an inch long and reminiscent of peppers. When ripe, the fruit are edible and are described as sweet and tomato-like. The fruit are not only popular for human consumption, but also for birds, deer, and raccoons. Just before we walked down the beach, another visitor saw a bobcat disappear into the shrub, which provides cover for many additional species besides those who eat it directly.
Illustration from a 15th century plant medicine book showing the mandrake, a member of the Solanaceae family.
Carolina wolfberry is a member of the Solanaceae family, aka nightshade (sometimes referred to as “deadly nightshade”). Other relatives include edible tomatoes, peppers, potatoes, eggplant, and groundcherry. The “deadly” part refers to related species like belladonna and mandrake, from which toxic poisons can be extracted. If you’re looking for a fascinating historical deep dive into these plants’ connection to witches, Shakespeare, and the death of multiple Roman emperors, look no further than the US Forest Service’s web page on the “Powerful Solanaceae” family!
Doodlebugs create pitfall traps in dry, sandy areas to lure unsuspecting ants. Their “doodles” in the sand are visible as well. Photo credit: Carrie Stevenson, UF IFAS Extension
It’s been years since I ran across doodlebugs. But when I saw a stretch of their pitfall traps at a campsite near Coldwater Creek in MIlton, I knew it was time to write about them. Lore says their silly name came from Southern kids like me, who watched the larvae drag their bodies around in the sand, leaving patterns (or doodles) etched behind them. These insects have long fascinated children and creative writers, with some of my favorite authors–Twain, Steinbeck, Thoreau–referencing doodlebugs in their books.
Doodlebug larvae are pretty terrifying, with those giant killer mandibles. Photo credit: UF IFAS
Doodlebugs, aka ant lions (Myrmeleon immaculatus—although we have 22 species in Florida!), are fascinating little insects that prey upon ants by creating slippery funnels in the sand. They wait underground below the funnel opening as unsuspecting ants march along the surface and slide down in the ensuing “mini avalanche.” If an ant or other prey item manages to get away, the ant lion can sling sand at it to try and knock it back down into the pit. Doodlebug larvae are the stuff of cartoon nightmares. They possess a pair of giant clawed mandibles, capable of grabbing and injecting prey with a toxin. The poison paralyzes the victim and contains digestive fluids which liquify its insides. At this point, the ant lion goes in for the kill by sucking out the prey’s juices through its deadly mandibles.
An adult doodlebug/ant lion bears no resemblance to its larval stage! Photo credit: Campbell Vaughn, UGA
Ant lions may stay in this frightening larval stage for up to 3 years. After this they undergo metamorphosis, spending 3 weeks in a cocoon. As adults, their transformation is dramatic; they are closely related to lacewings and dobsonflies, with long, thin bodies and large translucent wings.
A doodlebug captures its prey. Photo credit: UF IFAS
As kids, we always found doodlebugs under my best friend’s treehouse. In Milton, they were in a sandy area beneath a cabin roof overhang. These dry, protected sand areas are their preferred habitat and the best place to find them. We used to stick pine needles down into the openings, and watch as a flutter of insect mouthparts tried to grab it from us. Because of their fascinating life cycle and dramatic hunting technique, doodlebugs can be a captivating addition to a science classroom. In fact, there’s a reference to doodlebugs on the NASA website, due to an Apollo 16 astronaut’s mention of them. When landing on the moon, the craters reminded Charlie Duke of doodlebug pits, prompting him to recite an old children’s rhyme, “Doodlebug, doodlebug, are you at home?”
