Creating a wildlife haven one plant at a time

Wednesday, October 31, 2018

Discovering a Secret of the Franklinia alatamaha Tree

The Franklinia alatamaha tree was first discovered growing along a three mile tract on the banks of the Altamaha River in McIntosh County, Georgia, in 1765 by John and William Bartram. It has never been found growing anywhere else. William Bartram collected seed from this tree and brought it back to Bartram's garden in Philadelphia where it was successfully grown.

The Bartrams named the tree in honor of their friend Benjamin Franklin and the river beside which they found it. The species name 'alatamaha' reflects their variant spelling of Altamaha.

Extinct in nature since 1803, we are lucky that William Bartram had the foresight to grow this plant. All trees cultivated today come from the seed collected by Bartram. We purchased our tree from a local native plant nursery this spring. Already several years old, it bore beautiful camellia-like blooms during the summer much to the delight of several native bees.

Southern Meadows

It was later in the summer that I observed the leaves on the Franklin tree looking rather odd and it begged taking a closer look. I was astonished to find several fat caterpillars that I recognized as promethea moth larva.

Southern Meadows

They camouflage themselves well, their vibrant green bodies blending with the lighter hue of the underside of the leaves. The mature caterpillars have four bright red knobs called scoli behind their head and one yellow knob on their rear end.

Southern Meadows

I was not aware that Franklinia alatamaha was a host plant to this spectacular moth. Reference books list host plants as spicebush, sassafras, Chickasaw plum, ash, cherry, magnolia and tulip trees.

The caterpillars are pretty big eaters. They need to consume enough energy to sustain themselves in the pupal stage and into adulthood. As adults these moths do not eat so without proper nutrition at the larval stage they may not be able to complete their metamorphosis or produce eggs.

Southern Meadows

Already mature caterpillars when I discovered the seven on our tree, they were ready to begin forming cocoons. They do this by rolling up in one of the leaves and spinning brown silk around themselves. Anchored to the tree branch the pupa will remain in its cocoon over the winter months, emerging in spring.

Southern Meadows

The adults are gorgeous silk moths with eye spots and lightning bolt patterns. When they emerge they are ready to find a mate and continue the next generation.

Southern Meadows

The Franklin tree has a reputation of being difficult to grown. In the Piedmont region it is often susceptible to cotton root rot disease which contaminates much of the ground where this iconic crop was grown. If you are fortunate to grow one of these rare trees keep a watchful eye on its leaves. It just may reveal a special visitor to your habitat garden. 

Wednesday, October 24, 2018

Wildflower Wednesday: Aromatic Aster

Fall has finally arrived in Northeast Georgia. Persistently cooler temperatures set the tone this week for autumn, while the threat of frost on Sunday had us in a tizzy; hauling in the house plants that had enjoyed a summer hiatus in the garden, back indoors. Despite the recent lack of rain, the October garden has come alive with prolific autumn blooms. Our native asters are stealing the show.

In his book Bringing Nature Home Doug Tallamy describes asters as one of the top wildflowers that supports the most species of butterflies and moths. Not only do asters give color to our bright autumn days, but they are essential in supporting a variety of native bees, flies and butterflies that are active later in the year.

When we designed the wildlife hedgerow that sits above the retaining wall, which runs alongside the front driveway, we included several native asters as forage habitat for pollinators and songbirds. Several varieties of asters have been very productive over the past two growing seasons and filled in nicely.

The aromatic aster (Symphyotrichum oblongifolious) has been a standout. Thriving in the drier soil on this sloped terrain, it puts on quite a show for all those who drive by. This year it spilled over the retaining wall, creating a dramatic effect, but probably could have benefited from some mid-summer pruning.

Enjoying full sun, this aster is outfitted in blue blooms that dazzle the pollinators. The sound of buzzing bees is thunderous almost as if one where inside a hive. A closer look reveals a variety of bees from the more bodacious carpenter bees to the tiniest of sweat bees.

A wealth of butterflies flutter from one bloom to the next, dipping their long proboscis into the disk florets. Skippers are especially frequent visitors, but the aromatic aster also lures medium size butterflies with its sweet nectar. 

Syrphid flies that mimic bees also seek nectar and pollen. One could sit for hours being entertained by the diversity of pollinators this aster supports.

While all of these insects are foraging, they are providing important pollination services to the plant. Later in the season, game birds and song birds will feast on the seeds.

The Aromatic aster is an excellent landscape plant, prairie plant and habitat restoration species. It is extremely adaptable, growing happily in sandy, rocky and clay soils. It is drought tolerant, which is always a bonus in my book. Makes a great ground cover and is a host plant to several butterfly and moth species.

*Symphyotrichum oblongifolious is native to most Southeastern States (excluding Georgia and South Carolina).