False aloe

The name 'Manfreda' isn't in my Stearn’s Dictionary of Plant Names for Gardeners. Wikipedia states the name honors the 14th-century Italian, Manfredus de Monte Imperiale. He was an important scholar of medical botany. You can read more about him and other European minds who influenced botanical history in The Naming of Names: The Search for Order in the World of Plants.

A previous botanical name for Manfreda virginica was Agave virginica.

The most frequently used common name is False aloe, but it's also known as Virginia agave and Rattlesnake master. The common name of Rattlesnake master is problematic as it is typically used for a different but somewhat similar plant- Eryngium yuccifolium.

The photo below shows the flowers of Eryngium yuccifolium (the native wildflower more commonly associated with the name of Rattlesnake Master).

The tall spike bears up to 30 fascinating and fragrant flowers. These flowers are arranged on the top third of the spike, with the lower flowers opening first and gradually progressing towards the top. Each flower may have a short pedicel, which is the stalk that connects the flower to the spike. The swollen portion at the base of the flower is the ovary, while the showiest part is the anthers, which crisscross across the top and are beige to white with purple markings. These unique and interesting anthers are a sight to behold. The style of the flower is elongated, and the stigma, which is white and has three lobes, resembles a tiny flower.

Manfreda virginica is an agave plant arising from a bulb each spring. The thick, green leaves appear in late March to April and have a leathery feel. The lovely leaves may be completely green or decorated with purple splotches.

A tall stem or scape arises from the basal rosette in early summer. At maturity, the stem reaches a height between 3- 6 feet.

The delightful, clove-like fragrance of the flowers intensifies as dusk approaches and lingers until dawn. The sexual parts of the plant, both male and female, mature at different times, a phenomenon known as dichogamy. This strategy serves as a protective mechanism against self-pollination, thereby enhancing the plant’s diversity. Each tiny flower opens its petals in the early hours of the day. Later that same day, around dusk, the anthers, which produce pollen, dehisce and release the pollen. The next evening, the stigma, which is receptive to pollen, becomes receptive again and remains so until the following day. Nectar is found at the bottom of the calyx tube.

After blooming, fertilized flowers develop enlarged, green 3-celled capsules (fruits) that contain the developing seeds. Once the seeds ripen, the fruits become brittle, turning from green to a brownish tone and split open to spill their seeds. If opened before the seeds are spilled, rows of small, shiny black seeds will be seen inside each cell of the capsule. Seed dispersal can occur when the seeds fall from the opened capsules or when the scape falls to the ground at the end of the season.

Manfreda virginica has many pollinators, but much remains to be learned about them. The primary pollinators are likely night-flying hawk moths and other night-flying moths. Daytime visitors include snowberry clearwing moths (Hemaris diffinis), American bumblebees (Bombus pensylvanicus), common eastern bumblebees (Bombus impatiens), halictid bees, hummingbirds, and syrphid flies. However, it’s unclear which of these pollinators are most effective.

An interesting study by Groman et al. compared night and day insect visitors and their impact on seed set. They found that night-flying insects contributed to a higher seed set of Manfreda virginica compared to day-flying insects, even though more insects visited the flowers during the day. Interestingly, some day-visiting insects only sought pollen and didn’t come into contact with the female parts of the flowers.

Bumble bees are daytime visitors to Manfreda virginica. This video demonstrates a Common Eastern Bumblebee (Bombus impatiens) flying from one set of anthers to another, collecting pollen. Several Halictid bees are also seeking pollen from the anthers. The Bumblebee is significantly larger than the Halictid bees, and although they fly away when it lands, they are remarkably quick to return.

Another day time visitor is the Ruby throated Hummingbird. These speedy flyers are amazing to watch as they dart from flower to flower.

Lastly, here’s a beautiful Syrphid fly that has landed on a filament.

It’s intriguing that related species of Manfreda virginica found in Mexico are primarily pollinated by nectarivorous bats, yet this hasn’t been documented for Manfreda virginica.

Manfreda virginica is found in rocky, limestone glades as well as open woods and woodland edges. It grows in alkaline, shallow, rocky soils over limestone and dolomite bedrock — conditions that most plants find far too challenging to tolerate. What strikes me every time I encounter it in the wild is how it seems to thrive precisely where other plants give up. Glades tend to be fully exposed to the sun, while woodland edges offer dappled light, and Manfreda virginica handles both beautifully, growing happily in full sun to part shade.

Once established, it is extremely drought tolerant — well adapted to the hot, dry summers of the Ozarks. This is a plant that has made peace with adversity. It is particularly well suited to the Ozark region of Arkansas and Missouri, where limestone and dolomite glades are a defining feature of the landscape, and where I have had the pleasure of watching it grow season after season. In favorable glade habitat it can form large colonies, as the photo below shows — a breathtaking sight with dozens of tall scapes rising together in early summer.

Manfreda virginica is native to most of the eastern half of the United States as well as Texas and Oklahoma. Natureserve doesn't have a ranking available for all states in which Manfreda virginica is native. Where data is available, it is documented as Critically Imperiled in West Virginia, Imperiled in Virginia and Illinois, Vulnerable in Florida, Indiana and Ohio. There is no ranking for other states in which it is found (Alabama, Arkansas, Georgia, Louisiana, Mississippi, Missouri, Oklahoma, South Carolina, Tennessee and Texas.) If you are fortunate enough to encounter this remarkable plant in the wild, take a moment to appreciate its quiet resilience — and consider sharing your sighting to help build the knowledge that supports its protection.

In Arkansas, Manfreda virginica has a Conservation Value of 7 in the group of 4-7, meaning ‘Typically matrix taxa in intact stable habitats, with some limited ability to respond to destabilizing forces and repopulate areas from which they have been extirpated.’

While I've read that Manfreda virginica is a fairly deer and rabbit resistant plant, this is not my experience. I find deer particularly love consuming the basal leaves in early spring. They must taste delicious at this time! But they will also bite off the growing stems. Obviously there will be no flowers and no seeds set with either event. I'm not sure if the deer really like them or if they are just curious and decide to have a taste.

Although, they aren't pollinators, dragonflies enjoy using the tall stems of Manfreda virginica as posts to rest and spot their prey. This dragonfly is a Blue dasher (Pachydiplax longipennis).