Franklin Tree

By Kathy Jentz

The Franklin Tree (Franklinia alatamaha) is a small ornamental tree or large shrub. It is native to the southeastern United States and is hardy to USDA Zones 5 to 8. It is also known as Gordonia alatamaha or Gordonia pubescens.

It was named after founding father Ben Franklin. John Bartram and his son William discovered Franklinia growing along the banks of the Altamaha River in Georgia. The tree is no longer found in the wild, but is available in cultivation thanks to the original seeds gathered by the Bartrams.

Franklinia has a reputation for being difficult to grow, so it deserves a place of pride in a collector’s garden. It can be propagated from seeds or cuttings taken in early fall or by layering the lower branches.

The fragrant flowers bloom in mid- to late-summer and are an open Camellia-like blossom with bright-yellow stamens at the center of a ring of creamy-white, curved petals. It is in the tea family and is also related to Stewartia. The fall foliage color is attractive as well.

It prefers to be planted in part sun to part shade in rich but well-draining soils. It is susceptible to wilt and root rot. This tree resents being moved, so do not disturb the roots after planting it. o

Do I Need to Worry About Hammerhead Worms?

By Carol Allen

Should you worry about hammerhead worms? The immediate answer is, probably not. However, as our climate warms up, they might become more of an issue in the Washington, DC, metropolitan area.

Hammerhead worms enjoyed a bit of sensationalistic press earlier this summer after a reporter from the Washington Post encountered one at his home in Virginia. They are by no means common, but iNaturalist records 56 observations in Virginia over the last seven years, Maryland only has three since 2019, and there were none in the District.

Just what is this beast and what do we need to know?

Hammerhead worms are members of the phylum, Platyhelminthes, better known as flatworms. Most members of that phylum are aquatic, but the hammerhead worm of our concern can be referred to as a land planarian because it is fully terrestrial. It can be about a foot in length and is brown with stripes. It has a very distinctive hammershaped head.

The land planarian that has been identified in our region is Bipalium kewense. This invertebrate was probably native to southeast Asia, but is now found all over the world. Its preferred environment is warm and moist, and it is found more commonly in the tropics and subtropics. It was first discovered in American greenhouses in 1901 and is now found in greenhouses in many northern and central states. It seems to be spreading up the Atlantic Coast and has been observed overwintering in the northeast in sheltered sites. This invasive species moves throughout the world in potted plant material.

Hammerhead worms feed on earthworms, land snails, slugs, and insect larvae, and are cannibalistic. Some experts are concerned that if their population numbers increase, they can greatly reduce earthworm populations. They have been known to devastate earthworm farms. Maryland has a diminishing native earthworm population that is already feeling the pressure from imported nightcrawlers and Asiatic jumping worms (see “Where have all the Native Earthworms Gone?” in the August 2016 issue of Washington Gardener). Native earthworms co-evolved with the plants in this region. They break down leaf litter so that the system regenerates rather than degrades.

Perhaps more importantly, do hammerhead worms pose a threat to the health and well-being of humans and their pets?

Hammerhead worms subdue their prey by secreting an abundant amount of mucus that contains a neurotoxin, tetrodotoxin. Getting that neurotoxin containing mucus into your eyes or mucus membranes could cause a localized reaction. A physician should be consulted if the reaction is severe. Likewise, if a pet should encounter a hammerhead worm, they might react to the mucus. Contact your veterinarian in that case.

If you encounter one of these distinctive hammer-headed worms, wear gloves to avoid getting the mucus on your hands and slip them into a sealable plastic bag. They can be killed with the application of salt or alcohol, or being placed in either the sun or the freezer for a period of time. Do not cut them into pieces because that form of asexual reproduction is the one most often use by hammerhead worms.

Your chances of encountering these strange and creepy flatworms are unlikely. The worms are most active at night, though they might be spotted escaping the water-logged soil after a heavy rain. They cannot tolerate dry conditions and high humidity is essential to their survival. They are usually found under rocks, logs, or similar debris. They are reported to be more abundant in the spring and fall.

Currently, they are not being reported to any agency. A photo logged into iNaturalist will add to the growing population data. They are an invasive species, so it is recommended that they be dispatched by one of the methods described above o

Carol Allen describes herself as a committable plant-a-holic. She has more than 25 years’ experience in the horticulture industry, with a special interest in plant pests and diseases; is a Licensed Pesticide Applicator in the state of Maryland; and is an ISACertified Arborist. She can be contacted at carolallen@erols.com.