Sawtooth Oak:  A Good, Not Perfect Tree for Wildlife Enthusiasts

Sawtooth Oak:  A Good, Not Perfect Tree for Wildlife Enthusiasts

Since entering the U.S. from Eastern Asia in the 1920s and especially since its promotion as the ultimate wildlife tree in the last few decades, I doubt there has been a more widely planted tree by outdoor enthusiasts than Sawtooth Oak (Quercus acutissima).  It is easy to see the tree’s appeal.  Sawtooth Oak grows quickly relative to other oaks, rates of 3-4’ per year in youth are not uncommon.  It bears fruit at a very young age, as soon as five-seven years from seed, and produces a heavy crop almost every year, unlike many native oak species.  Mature specimens are also mostly pest/disease free and very attractive, reaching 40-60’ in height with sweeping, wide-spreading branches, and deep, furrowed bark. 

While it seems that I just described the ideal wildlife tree, and Sawtooth Oak can indeed be a worthy inclusion to your property, it is not perfect.  All too often I see landowners and hunting lease holders plant solely Sawtooths as a part of their mast-producing tree strategy.  As in other areas of life, avoiding monocultures and adding a little diversity to your wildlife tree portfolio is beneficial.  Keep that, and the following lessons I’ve learned the hard way, in mind when you consider adding these wildlife attracting trees to your property.

  1. Acorns Drop Early – Sawtooth Oaks produce all their acorns very early in the season, beginning in September.  Conversely, most of our native oaks drop their mast (a fancy word for tree fruit) during the winter months that comprise our main hunting season, November-January.  So, while Sawtooth Oak is an excellent wildlife attractor and most any creature will readily gobble up their acorns, if you plant them to hunt around or provide a critical winter food source, you’ll likely be disappointed. 
  2. Invasive Potential – As Sawtooth Oak is non-native, very adapted to the Southeastern U.S. climate, and produces literal tons of acorns each year, the species has the potential to become a nuisance invasive.  I’ve visited several sites over the last few years that had a couple of large Sawtooth Oaks planted in areas mostly excluded from wildlife pressure.  I was surprised to see small Sawtooth saplings popping up everywhere.  It was eerily reminiscent of other nuisance trees like Chinaberry and Camphor.  Though I don’t think Sawtooth Oak will ever be a problem on the level of Chinese Tallow or Cogon Grass, it’s wise to use caution with plants that have invasive potential.
  3. Less Nutritious Acorns – Sawtooth Oak acorns are heavily browsed, but it’s not necessarily because they’re extremely nutritious.  A study from the 1960s compared the nutritional quality of Sawtooth Oak acorns to 8 common native oak species and found Sawtooth lagged the natives by a significant margin in all macronutrients measured:  protein, fat, and carbohydrates.  This finding suggests that, while Sawtooth Oak is an excellent wildlife attractor, if your goal is growing higher quality game animals and providing valuable nutrients to get them through the winter when wildlife forages are scarce, Sawtooth Oak should be a minor component of your strategy, not the endgame.
  4. Longevity – The jury is still out on longevity.  However, anecdotal evidence from around the Southeast suggests that Sawtooth may not be as long-lived as some of our native oaks.  This could be due to several factors.  First, as a rule, extremely fast-growing trees tend to be shorter lived due to weaker branching structure, less dense wood, and other factors.  Think of the tortoise and the hare analogy.  The quickest do not always win the race.  Second, Sawtooth Oak did not hold up particularly well during Hurricane Michael and other strong storms.  Their growth habit (heavy, wide spreading branches low to the ground) is not conducive to major wind resistance.  This is to be expected as Sawtooth Oak is native to areas that do not experience tropical wind events and likely evolved accordingly.

I am by no means suggesting that you shouldn’t add Sawtooth Oak to your property in the hopes of encouraging wildlife.  There are few trees available that do a better job of that.  I am suggesting that Sawtooth Oak should be a small part of your larger overall planting strategy and you should keep in mind the potential drawbacks to the species.  Plant mostly native oaks, allow Sawtooth Oak to be merely a supplement to them, and I think you’ll be pleased with the results!  Putting all your acorns in one basket is rarely a good strategy.

For more information on Sawtooth Oak, other wildlife forage and attractant strategies, or any other natural resource, agronomic or horticultural topic, please reach out to your local UF/IFAS Extension Office!

Mistflower (Conoclinium coelestinum)

Mistflower (Conoclinium coelestinum)

October is the premier wildflower month in the Panhandle.  Nighttime temperatures drop, days shorten, pollinators emerge, and many native plants explode into flower.  Of all the native fall-flowering Panhandle wildflowers, maybe the most striking is currently in full bloom, the Mistflower (Conoclinium coelestinum)! 

Blue Mistflower. Photo courtesy of Bill Booth / Natural Encounters.

Mistflower is a low growing, spreading native (1-2’ in height) found in sunny, moist areas of meadows and near rivers, ponds, and creeks throughout much of the United States from New York to Florida and even west as far as Texas and Nebraska.  This common native wildflower is conspicuously one of the few native plants in our area that has blue flowers, making Mistflower easy to spot in a sea of yellow, orange, purple, pink, and white wildflowers.  The flowers appear as little puffs of purply-blue due to the lack of ray florets (think of the outer yellow “petals” of sunflowers), possessing only disk florets (think of the inner part of sunflower heads) with long blue, fuzzy-appearing stamens.   Mistflower is attractive to more than just wildflower watchers as well, it’s a magnet for nectar-seeking butterflies such as the Eastern Swallowtails, Great Purple and Juniper Hairstreaks, and others. 

Great Purple Hairstreak butterfly on Mistflower. Photo credit Bill Boothe / Natural Encounters.

As lovely as Mistflower is in the wild, it’s probably best left for folks enjoy there, especially those who prefer an orderly yard.  Mistflower will indeed grow great in moist areas of pollinator gardens and landscapes, requiring only ample sunlight and rainfall, but it is very aggressive.  Its spreading nature via its rhizomatous root system and prolific seed production often lead to it becoming a weedy nuisance in more manicured landscapes.  But, if chaos and fall bursts of blue erupting at random throughout your garden don’t bother you, by all means, seek out Mistflower for purchase through seed catalogs and local native nurseries.  For more information on Mistflower and other fall-blooming native wildflowers, contact us at the UF/IFAS Calhoun County Extension office!  Happy Gardening.

False Foxglove:  A Unique Fall Wildflower

False Foxglove: A Unique Fall Wildflower

Fall is the absolute best season for wildflower watching in the Panhandle!  When mid-September rolls around and the long dog days of summer finally shorten, giving way to drier air and cooler nights, northwest Florida experiences a wildflower color explosion.  From the brilliant yellow of Swamp Sunflower and Goldenrod, to the soothing blue of Mistflower, and the white-on-gold of Spanish Needles, there is no shortage of sights to see from now until frost.  But, in my opinion, the stars of the fall show are the currently flowering, beautiful pink blooms of False Foxglove (Agalinus spp.).

False Foxglove in a Calhoun County natural area. Photo courtesy of Daniel Leonard.

Named for the appearance of their flowers, which bear a resemblance to the northern favorite Foxglove (Digitalis spp.), “False Foxglove” is actually the common name of several closely related species of parasitic plants in the genus Agalinus that are difficult to distinguish by all but the keenest of botanists.  Regardless of which species you may see, False Foxglove is an unusual and important Florida native plant.  Emerging from seed each spring in the Panhandle, plants grow quickly through the summer to a mature height of 3-5’.  During this time, False Foxglove is about as inconspicuous a plant as grows.  Consisting of a wispy thin stem with very small, narrow leaves, plants remain hidden in the flatwoods and sand hill landscapes that they inhabit.  However, when those aforementioned shorter September days arrive, False Foxglove explodes into flower sporting sprays of dozens of light purple to pink tubular-shaped flowers that remain until frost ends the season.

False Foxglove flowering in a Calhoun County natural area. Photo courtesy of Daniel Leonard.

In addition to being unmatched in flower, False Foxglove also plays several important ecological roles in Florida’s natural areas.  First, False Foxglove’s relatively large, tubular-shaped flowers are the preferred nectar sources for the larger-sized native solitary and bumble bees present in the Panhandle, though all manner of generalist bees and butterflies will also visit for a quick sip.  Second, False Foxglove is the primary host plant for the unique Common Buckeye butterfly.  One of the most easily recognizable butterflies due to the large “eye” spots on their wings, Common Buckeye larvae (caterpillars), feed on False Foxglove foliage during the summer before emerging as adults and adding to the fall spectacle.  Finally, False Foxglove is an important indicator of a healthy native ecosystem.  As a parasitic plant, False Foxglove obtains nutrients and energy by photosynthesis AND by using specialized roots to tap into the roots of nearby suitable hosts (native grasses and other plants).  As both False Foxglove and its parasitic host plants prefer to grow in the sunny, fire-exposed areas pine flatwoods and sand ridges that characterized pre-settlement Florida, you can be fairly confident that if you see a natural area with an abundance of False Foxglove in flower, that spot is in good ecological shape!

The Florida Panhandle is nearly unmatched in its fall wildflower diversity and False Foxglove plays a critical part in the show.  From its stunning flowers to its important ecological roles, one would be hard-pressed to find a more unique native wildflower!  For more information about False Foxglove and other Florida native wildflowers, contact us at the UF/IFAS Calhoun County Extension office.

 

Overcup Oak – The Best Native Landscape Tree You’ve Never Seen

Overcup Oak – The Best Native Landscape Tree You’ve Never Seen

Overcup on the edge of a wet weather pond in Calhoun County. Photo courtesy of Daniel Leonard.

Haunting alluvial river bottoms and creek beds across the Deep South, is a highly unusual oak species, Overcup Oak (Quercus lyrata).  Unlike nearly any other oak, and most sane people, Overcups occur deep in alluvial swamps and spend most of their lives with their feet wet.   Though the species hides out along water’s edge in secluded swamps, it has nevertheless been discovered by the horticultural industry and is becoming one of the favorite species of landscape designers and nurserymen around the South.  The reasons for Overcup’s rise are numerous, let’s dive into them.

The same Overcup Oak thriving under inundation conditions 2 weeks after a heavy rain. Photo courtesy Daniel Leonard.

First, much of the deep South, especially in the Coastal Plain, is dominated by poorly drained flatwoods soils cut through by river systems and dotted with cypress and blackgum ponds.  These conditions call for landscape plants that can handle hot, humid air, excess rainfall, and even periodic inundation (standing water).  It stands to reason our best tree options for these areas, Sycamore, Bald Cypress, Red Maple, and others, occur naturally in swamps that mimic these conditions.  Overcup Oak is one of these hardy species.  It goes above and beyond being able to handle a squishy lawn, and is often found inundated for weeks at a time by more than 20’ of water during the spring floods our river systems experience.  The species has even developed an interested adaptation to allow populations to thrive in flooded seasons.  Their acorns, preferred food of many waterfowl, are almost totally covered by a buoyant acorn cap, allowing seeds to float downstream until they hit dry land, thus ensuring the species survives and spreads.  While it will not survive perpetual inundation like Cypress and Blackgum, if you have a periodically damp area in your lawn where other species struggle, Overcup will shine.

Overcup Oak leaves in August. Note the characteristic “lyre” shape. Photo courtesy Daniel Leonard.

Overcup Oak is also an exceedingly attractive tree.  In youth, the species is extremely uniform, with a straight, stout trunk and rounded “lollipop” canopy.  This regular habit is maintained into adulthood, where it becomes a stately tree with a distinctly upturned branching habit, lending itself well to mowers and other traffic underneath without having to worry about hitting low-hanging branches.  The large, lustrous green leaves are lyre-shaped if you use your imagination (hence the name, Quercus lyrata) and turn a not-unattractive yellowish brown in fall.  Overcups especially shine in the winter when the whitish gray shaggy bark takes center stage.  The bark is very reminiscent of White Oak or Shagbark Hickory and is exceedingly pretty relative to other landscape trees that can be successfully grown here.

Finally, Overcup Oak is among the easiest to grow landscape trees.  We have already discussed its ability to tolerate wet soils and our blazing heat and humidity, but Overcups can also tolerate periodic drought, partial shade, and nearly any soil pH.  They are long-lived trees and have no known serious pest or disease problems.  They transplant easily from standard nursery containers or dug from a field (if it’s a larger specimen), making establishment in the landscape an easy task.  In the establishment phase, defined as the first year or two after transplanting, young transplanted Overcups require only a weekly rain or irrigation event of around 1” (wetter areas may not require any supplemental irrigation) and bi-annual applications of a general purpose fertilizer, 10-10-10 or similar.  After that, they are generally on their own without any help!

Typical shaggy bark on 7 year old Overcup Oak. Photo courtesy Daniel Leonard.

If you’ve been looking for an attractive, low-maintenance tree for a pond bank or just generally wet area in your lawn or property, Overcup Oak might be your answer.  For more information on Overcup Oak, other landscape trees and native plants, give your local UF/IFAS County Extension office a call!

The Spiderwort

The Spiderwort

The brilliant purple, edible spiderwort flowers are only around for a day! Photo credit: Mary Anne Tomlinson

The spiderwort is a pretty little plant that most people have encountered in their yards or on roadsides. In cattle or hay pastures, it is considered a weed because cows won’t eat it, and its high moisture content can ruin hay harvests. In a home landscape, though, it can be a nice addition to the yard. I know many homeowners who refuse to let them be mowed down with the lawn simply because of their brilliant color. The native spiderwort (genus Tradescantia) is a perennial flower that grows in clusters, often in moist soils. It is a member of the dayflower family, which means each flower is only open for a single day.  The plant, a favorite of bumblebees, can be identified quickly by its triad of violet petals and bright green, strap-like leaves.

Spiderworts bloom in spring and grow in clumps of bright green, strappy leaves. Photo credit: Mary Anne Tomlinson

Known by common names as varied as “Bluejacket,” “Snotweed,” and “Cow Slobber” (due to the mucilaginous—mucus-like–consistency of its sap), the plant is widespread throughout the eastern and central United States. An interesting aspect of this sap is that it can be used as a salve for insect bites, similarly to aloe. Even more useful for those interested in native edible plants is that the flowers, stems, and leaves can be eaten raw in a salad or cooked and used as a culinary herb. The flowers can be candied with sugar as a dessert or used atop cakes.

Interestingly, the spiderwort can also indicate the presence of radiation. The bluish hairs on spiderwort flower stamens will turn pink in the presence of low levels of radiation, often more reliably than mechanical dosimeters.