Book Review: The World of Clovers

By John M. Gillett and Norman L. Taylor, Michael Collins (Editor)

Reviewed by Jonathan O.C. Kubesch, University of Tennessee—Knoxville

Author’s Note: True clovers (Trifolium spp.) are the focus of this article. All scientific names abbreviate Trifolium to T.

The World of Clovers, by John M. Gillett and Norman L. Taylor (2001), is a fantastic primer on the global diversity of the genus Trifolium. Conceived in concert with a world seed collecting effort, Gillett and Taylor work to describe the many known species of this familiar genus. The global distribution of the genus is discussed and the book highlights origins for these species. Native clover species form intriguing distributions. This book covers details in morphological diversity beyond the traditional field guide using photographs. Notes cover the trivial and surprisingly nuanced characteristics of each species. In the 20 years following publication, some new information has developed about these species in the genus Trifolium. However, the book is a strong introduction for the botanist to explore a wider world of clovers.

This book is especially relevant to Kentucky botanists. Norman L. Taylor sought to collect every known species of clover and seed bank them in Lexington, KY. This work led to a framing of the genus (~230 species) with ever-expanding global coverage. Clovers are native to North and South America, Africa, Europe, and the Near East. Surprisingly, clovers are not native to Australia! The Great Plains and Coastal Plain have few native clovers, but the woodland-grassland mosaic of the Southeastern United States supports a handful of native species, such as the running buffalo (T. stoloniferum), Carolina (T. carolinianum), and running glade clovers (T. calcaricum) in addition to the introduced Eurasian species, such as red (T. pratense) and white clovers (T. repens).

The World of Clovers appeals across disciplines and levels. Gillett and Taylor seek to make the diagnostic information as accessible as possible, using common language to avoid a technical glossary. The description and photograph accompanying each species’ seed suits the conservation mission. The black-and-white images on the pages are complemented by an enclosed CD. Moving beyond the traditional field guide or agronomic factsheet, the book gives reproductive biology information. This reproduction section of each species entry suits efforts to propagate plants in cultivation or to encourage success in the wild. The number of cross-pollinated species draws additional attention to the plight of pollinators.

Clovers have served primarily as forages for wildlife and livestock. However, the horticultural benefits of these species also come to mind. The authors mention Kura clover and buffalo clover as two prominent candidates for their ornamental beauty. Of buffalo clover, as an extension of Norman Taylor’s personal fondness, Clovers says, “Many consider this species the most beautiful of the clovers….” In addition to the technical details, these small comments offer some humanity to the often impersonal business of plant sciences. New finds in the taxonomy of the clovers have led to the identification of a new species, Kentucky clover (T. kentuckiense), which is closely related to buffalo clover (T. reflexum)(Chapel and Vincent, 2013).

In 20 years of scientific and economic advancement the world of clovers has changed. Taylor passed in 2010, and his collection was split between Washington State and Georgia USDA seedbanks. Similarly, the use of clovers in agricultural settings has expanded to develop living mulch and perennial ground cover systems. Clovers will hopefully reduce the use of synthetic inputs in agricultural to the benefit of adjacent natural ecosystems.

Dr. Michael Vincent’s 2001 summary of Kentucky’s Trifolium, complements the World of Clovers in further detail on the 11 (now 12 due to the subsequent discovery of T. kentuckiense) species seen in Kentucky (Vincent, 2001). Clovers are part of the historical herbivory and current cropping of the state. This book is a limited description at the species level which the ecologist may apply in conjunction with similar guides on the KY flora.

The World of Clovers is useful to professional and citizen scientists because it encompasses the diversity of the genus. This book goes beyond the traditional field guide, but also comes in an accessible form for the everyday user. Clovers exist under cultivation as well as in Kentucky’s natural areas. The genus Trifolium has grown in a small degree in the time since publication, but the book offers wider coverage that serves both the hiker and horticulturalist.

Acknowledgements

Norman Taylor deserves special mention to his dedication in preserving the native clovers of Kentucky. This article is part of the ongoing efforts of the Kentucky Clover Recovery Team. Will Overbeck provided helpful suggestions and strong editorial contributions. Special thanks to David Barker, Daniel Boone, and Ken Quesenberry for recommending this book. Thanks to Sarah Grace Holland, for her supporting my native clover research.

References

Chapel, K. J., & Vincent, M. A. (2013). Trifolium kentuckiense (Fabaceae, Papilionoideae), a new species from Franklin and Woodford counties, Kentucky. Phytoneuron 2013-63: 1–6.Chapel and Vincent 2013.

Gillett, J. M., & Taylor, N. L. (2001). The World of Clovers. Ames, IA: Iowa State University Press.

Vincent, M.A. (2001). The genus Trifolium (Fabaceae) in Kentucky. J. Ky. Acad. Sci. 62(1):1-17.


Jonathan Omar Cole Kubesch is a graduate student pursuing a master’s degree in crop science at the University of Tennessee. He studied evolution and ecology—as well as agronomy—at the Ohio State University. He works on forages, grasslands, and prairies with a particular passion for native clovers. 

Native spotlight: Hepatica

By Susan Harkins

Kentucky doesn’t have many winter-hardy wildflowers, so gardeners plant non-natives—daffodil, crocus, and hellebore mostly—to brighten up their early spring yards. By the end of February, I’m crabby and needing a respite and those early blooms sooth my soul and remind me that within a few weeks the world will be warm and full of color again. Daffodils bridge the gap between my “I’m going to die…” stage and “Ah! Spring!” You don’t have to rely on non-natives though, thanks to Hepatica.

Shenandoah National Park

Hepatica isn’t Kentucky’s earliest native bloomer. That distinction probably goes to Symplocarpus foetidus, commonly known as skunk cabbage or polecat weed. Unless you have a shady bog to fill, you probably can’t rely on skunk cabbage to scout out spring. The next earliest native bloomer is Hepatica. By mid-April, they’re everywhere, but I’ve spied them earlier.

If they bloomed any later, these small delicate flowers would be totally overwhelmed by the riotous outbreak of warmer spring colors. Somehow, they arrive at just the right time.

Kentucky claims two varieties: Hepatica americana and Hepatic acutiloba. You might once have known this native as Hepatica nobilis, but that is the European species and it no longer applies to our Kentucky species.

Botany

Tiny hairs protect the tender buds that often push through late snow. If you examine them closely, they look fuzzy, as if they’re wearing fur caps for protection. Hairs also protect the stems and leaves, and it’s possible the hairs help retain heat. They are “evergreen,” living a full year.

Blooms appear in a variety of colors: white, pink, lavender, purple, and blue. Their “petals” are actually sepals held in place by three bracts. The number of sepals varies, and they last for weeks. Heart-shaped leaves grow at the stem’s base. Hepatica means liver in Latin, and the name is derived from its liver-shaped winter leaves. That also explains its common names, liverwort and liverleaf.

Once the sepals die, a set of new leaves emerge to continue soaking in the sun’s ray, storing up energy for next spring’s early blooms. As winter moves in, the leaves darken until they seem to disappear, but they’re ready to start photosensitizing with spring’s first hint of sun. That “evergreen” leaf is the reason Hepatica can bloom so early in the spring.

You might wonder how this flower pollinates considering how few insects are out and about in early spring. Cross-pollination by an insect, such as solitary bees, is preferred, but this plant is autogamous–it can fertilize itself!

In your garden

Besides keeping you sane until spring truly erupts, this little beauty makes a lovely garden plant. Once established, they spread quickly and form little clumps of flowers that are a sweet complement to crocus and other non-native spring bloomers.

Plant Hepatica in a moist rich soil that receives only a few hours of sun (not full shade). Because they can so easily be obscured, plant them in mass or among ornamental rocks. They need good air flow to prevent leaf spotting.

Fortunately for gardeners, Heptica grows easily from seed. The small seeds are ready to collect in late spring; if the seeds aren’t easy to remove, they’re not ripe. It’s easier to cut the entire star-shaped seed cluster into a bag than to collect only the seeds because of their small size. The seeds are still green when ripe and need a period of warm stratification, followed by cold stratification before they will geminate. For that reason, I recommend that you sow them immediately.

Seeds germinate and produce seed leaves the next spring. They’ll produce flowers their second year, so plan ahead. If you’re germinating in flats, prepare to keep them for two years before transplanting.

Whether you’re a native purist or simply looking for a bridge into spring, consider Hepatica. It’s so delicate that it hardly seems possible that it has survived the harsh winter, but year after year, it not only returns, it celebrates, and we celebrate in kind.

Huron-Manistee National Forests

Native Spotlight: Sporobolis heterolepis

By Susan Harkins

A few summers back, I stopped outside a local nursery to admire a huge pot of Sporobolis heterolepis, commonly known as prairie dropseed. I gently caressed the long thin green leaves and tiny brown seeds. Not only was the tactile sensation comforting, the released fragrance, similar to cilantro, was mesmerizing. It grows in my yard, but I thought to myself then that the next year I would have a pot of dropseed on my porch. Someone knew what they were doing when they positioned that pot of dropseed at the entrance to the store.

This native grass is aptly described as an elegant fountain. Its fine-textured arching leaves grow up and curve down toward the earth. Loose branching clusters of airy florets produce tiny fragrant brown seeds. This time of year, when our fields and yards are a blaze of yellow and purple, dropseed offers lovely spots of gold, orange, and pink.

Botany

Sporobolis heterolepis is a warm-season deciduous bunchgrass, which simply means it grows in clumps. The 3 to 8 inch panicle comprises multiple branches that terminate in small spikelets. A single floret has three reddish anthers and a short feathery stigma when in bloom. Once pollinated (by wind), the floret produces a mostly round small seed in a hard hull. It’s a dense turf with alternate basal leaves.

Culture

This drought-tolerant native prairie grass is often used to fight erosion and control water runoff because of its deep fibrous root system. As you might expect, it grows well in dry soil and full sun. Because it tolerates heavy clay, it’s a good species for Kentucky gardens. It also grows in glades and open areas left by human development.

I’ve found that this perennial likes a bit of room. If too crowded, they don’t reach their normal 2 to 3 feet in height and spread.

Propagation

Seeds are best collected in October before they drop from their hulls. They germinate in cool weather so sow in the late fall or early spring; they require stratification if sown in the spring. (An easy stratification method is to sow in dry soil for at least ten weeks.) Although Sporobolis heterolepis grows easily from seed, it’s not a prolific self-seeder, so don’t expect it to fill in as ground cover. Division is possible, but difficult because of its dense root system. Many experts recommend divisions over seeds, but I’d rather seed heavily or buy mature plants than take a chain saw to the roots because that’s the only way I’d be successful!

In your garden

Due to its late blooming florets, this species is a fall beauty, and its arching leaves lend elegance almost year round. Snow doesn’t flatten the leaves and the graceful leaves and seeds poking through a new snow are lovely.

A mass planting of Sporobolis heterolepis.

Plant in mass or as a single focus point. However, I don’t recommend them as a formal border because this species is diverse in form from plant to plant. They’re not a cookie-cutter plant. Plant 18 to 24 inches apart and don’t crowd them. It can hold its own against Andropogon gerardii, big bluestem, and Sorghastrum nutans, Indian grass, but don’t allow nearby taller plants to block the sun; placement is important when combining Sporobolis heterolepis with taller prairie grasses.

Patience is a virtue, so they say, and you’ll need it with this species when growing from seed or plugs. It takes nearly five years to fully develop from seed, so I recommend buying large plants if you want a quick display from this plant. Once established, this grass requires little care, but keep it well watered the first year. Dethatch it once a year and remove weeds; that’s it!

If you garden for wildlife, the seeds persist into winter providing food for birds. Its clumping nature provides habitat and protection for birds and small mammals and nesting material and shelter for native bees.

Although it’s slow to establish, Sporobolis heterolepis is one of the showiest bunch grasses. It fits into almost any landscaping theme, from formal to rustic. It’s a great plant for restoration projects and is trouble free once established. But for me, the fragrance is its most endearing quality—put a pot on your porch and enjoy.

Pollinators of Native Plants: A Book Review

Written by Heather Holm; Published by Pollination Press, LLC

Reviewed by Susan Harkins

I’m fond of saying that my favorite flower is the one I’m looking at. Similarly, my favorite book is the one I’m currently reading. However, when I say that Heather Holm’s Pollinators of Native Plants is one of my favorite books, I mean it. I keep just a few reference books close at hand, and this book is one of them.

It’s the most comprehensive, photo-filled book I’ve found on identifying the native pollinators that depend on our native flora. Every plant has a two-page spread that contains what you need to know about that plant to determine if it’s a good fit for your property and a full page or more of all the native pollinators it will attract. You get a full picture.

Its use goes beyond identifying pollinators: it’s one of the first books I pull out when wanting information about a particular plant, with or without consideration of its pollinators. However, when I want to identify a pollinator, it’s my go-to book. Often, I’m looking for host plants. This book supplies that information plus clear pictures of the pollinator in larvae form, which is invaluable when determining if I have an invading force in the yard or I’m seeing normal wear and tear by native beneficials.

The largest part of the book comprises the two-page spreads of 65 native plants. A few chapters in the beginning offer general advice from anatomy to ecothreats. At the end of the book, you’ll find visual botany glossaries, charts, garden designs, and more.

Pollinators of Native Plants is an outstanding reference on native trees and flowers that support our native pollinators. The detailed yet friendly layout make it easy to apply the information to your own property.

Heather Holm currently lives in Minnesota where she assists with native been research projects, the most recent being a study on native pollinators and cultivated blueberries. As a community supporter, she helps restore city-owned property for pollinators and people. You can keep up with Heather’s speaking engagements here: https://www.pollinatorsnativeplants.com/.


Susan Harkins is the Managing Editor of The Lady Slipper.

The Life Cycles of Butterflies

Authors, Judy Burris and Wayne Richards; Publisher, Storey Publishing

Reviewed by Susan Harkins

When authors Judy Burris and Wayne Richards were kids, they spent most Saturdays in the woods with their mother. Those early adventures turned into a passion for bugs—lucky me! I say lucky me because Judy and Wayne channeled that passion into one of my favorite books, The Life Cycles of Butterflies.

This award-winning book, originally written for children, is a great resource for all ages. After an informative and creative introduction to butterfly anatomy and life cycle, the remaining book focuses on individual species. Four consecutive pages are packed with gorgeous photos and useful information on a single species. Within those four pages you’ll see pictures of the species’ egg, chrysalis, caterpillar, and adult. You’ll also see host and nectaring plants, and read interesting facts such as breeding range, average wingspan, and so on.

If you’re educating or entertaining children, you have all you need from the get-go. The book tells you what to plant to attract a specific species and then helps you identify what wanders into your yard and sets up a nursery. It’s easy to take this book out into the yard and quickly identify a species by egg, chrysalises, or caterpillar. But you don’t need to be a child to appreciate this book.

Perhaps the back cover is my favorite part; it’s covered with pictures of butterflies common to our region. Often, I don’t even open the book. Rather, a glance helps me identify an adult quickly with little effort, and before it flies away–that beats a traditional field guide in my book!

Even though this book is marketed as a children’s book, it is a tremendous resource in any adult library.

It’s important to note that not all plants mentioned in the book are natives, although an asterisk marks invasives. Be sure to do your homework before purchasing plants. The authors are available for public programming.

Native spotlight: Baptisia australis

By Susan Harkins

As the song goes, June is busting out all over! No month is kinder to Kentucky wildflowers than June. The delicate and often elusive ephemerals have given way to an abundance of rambunctious textures, colors, shapes, heights, and fragrances. If you love wildflowers, you have to love June. Maybe that’s why so many brides choose June—it’s all about the bouquet! A spectacular bouquet will include Baptisia australis. Regionally, you might know this species as wild blue indigo or false blue indigo.

There’s something magical and exotic about this flower—its structure is so different from what we usually see in our gardens. I expect to see fairies flitting about as the sun sets and the moon begins its climb into the night sky. I tell my grandchildren if they want to see fairies, that’s the flower to watch.

Baptisia australis
Tim Waters

Botany and wildlife

Baptisia is in the legume (Fabaceae) or pea family, which explains the bloom’s departure from the more familiar trumpet and ray flowers. In addition, Baptisia has both male and female flowers. The blooms mature from the bottom up, and the older female flowers produce lots of nectar. Blooms toward the top of the stalk are pollen-rich males.

Donna Long

A bumble bee travels to the preferred lower flowers, seeking their nectar prize. The bee grasps the female’s pistils and thrusts itself inside the bloom. Eventually, the bee makes its way up the stalk, reaching the male flowers. This same propelling action brushes the pollen-covered anthers across the bee’s abdomen. After reaching the top, the bee flies to the female flowers at the bottom of the next stalk, depositing its pollen onto the female pistils.

The blooms also attract butterflies and hummingbirds, and Baptisia is the only known host of the Wild Indigo Duskywing (Erynnis baptisiae) butterfly.

Another native Baptisia is Baptisia alba. It’s similar in every way to australis but its blooms are white. There’s a yellow variety, Baptisia sphaerocarpa, but it isn’t native to Kentucky.

Culture

When Mary Carol Cooper gave me my first Baptisia, she advised me to find a sunny spot and leave it there. They grow a long taproot and don’t like to have their roots disturbed. Besides, you might not be able to move it even if you decide to. Established plants resemble asparagus when they break ground in early spring but underneath, the roots are woody. I’d describe the roots as a steel octopus. Established Baptisia is almost impossible to dig up without superpowers.

They prefer fun sun but will tolerate a bit of shade. They’re very forgiving in their water needs, so go for sun first, then water. However, they need well-drained soil. Steer clear of high pH soils or amend the soil regularly if necessary. Baptisia blooms from April to July. If they stay small and the leaves are a bit yellow, pH might be your problem. They take a few years to produce volumes of blooms, but they are worth the wait.

Propagation

Given Baptisia’s rooting disposition, division isn’t a great method of propagation. Cuttings will root but few will sprout the next spring.

Leonardo Dasilva

Seeds are the way to go. To collect, wait for the pod to turn brown or black. Blooms persist toward the top while pods ripen along the bottom. Fortunately, they hang on to the plant for weeks so they’re easy to find. Store dry seeds in the refrigerator. They’re easy to germinate and require only 10 days of cold moist stratification and then scarification in hot water. Plant about ½ inch deep.

Because Baptisia is a legume, it requires microorganisms that inhabit nodules on the plant’s root system. If you’re purchasing a healthy plant, don’t worry about it. You might never need to know this, but it can’t hurt to tuck away this bit of botanical trivia in your brain’s gardening section.

In your garden

In nature, you’ll find Baptisia along moist woodland edges and prairies. In your garden, give special care not to crowd them. They grow large and bushy so give them lots of room. The blooms are small, but the volume creates a showy vertical display. You might want to surround them with a bit of ground cover but don’t ask them to compete with another showy plant.

This bushy perennial grows from two to four feet from its woody base. While not a shrub, one plant can spread to three feet. One Baptisia is beautiful and three make a breathtaking display. However, in my opinion, a mass planting loses its visual impact because you see only the color and not the individual, and spectacular, plant.

Baptisia of any color provides both height and depth to any sunny garden spot. It’s spectacular as a focus spot or in a perennial border with other natives. After blooming, its blue-green foliage makes a nice backdrop for later bloomers and persists into cooler weather as do the dark seed pods.

When purchasing plants, look for older plants that are blooming; from seed, this plant takes three years (and patience) to produce flowers. Give Baptisia what it needs, and not only will it take center stage, but it will also be hearty—to the extent of being almost indestructible.

America’s favorite, Lobelia cardinalis

By Susan Harkins


Roger Tory Peterson described this midsummer bloomer as America’s favorite flower, and with good reason. Its blooms are an intense scarlet, which makes it attractive to both us and hummingbirds. You’ll hear Kentucky gardeners refer to Lobelia cardinalis as cardinal flower and red lobelia. Supposedly the name comes from the vestments worn by Roman Catholic cardinals; still others say it’s named for our state bird, the cardinal. The color is spectacular, regardless, as the blooms reflect one of the deepest, truest reds to be found in nature.

With all this natural beauty comes an unfortunate reality: They can be difficult to grow in our own gardens. L. cardinalis isn’t as forgiving as other natives that seem to thrive on our neglect. Providing what it needs is the key to success. But first, let’s take a short botany lesson.

Botany and wildlife

Not only are the red flowers attractive to hummingbirds, but the bloom’s shape plays a part in its success. Each bloom is a long tube, and at the bottom is a few drops of nectar. This shape is perfectly suited to the hummingbird’s long beak and tongue. When a hummingbird visits, it touches its head to the pistil and stamen, (reproductive organs), which stretch beyond the tube’s outer edges.

Culture and propagation

I’m combining these two topics because this is where L. cardinalis is a bit unforgiving. You can plant dozens and they might be gorgeous that first summer, but they might not return the next year—they might never return. Some gardeners love them so much that they treat them as an annual, replanting every year. This species needs good sunlight, but more importantly, moist soil, if you want them to return every year.

Lobelias aren’t true perennials; after setting seed, the stem and root system dies. New plants grow from the plant’s axil (the angle between the upper surface of a leaf and the stem it’s attached to). Although they grow quickly, they remain close to the ground and are obscured by the foliage above. Instead of seeds lying dormant in the soil all winter, you have evergreen seedlings that need tender loving care that first winter.

Keeping the new growth free of debris is vital, otherwise, the small rosettes don’t get the sunlight they require. Unfortunately, many of us add mulch in the fall and winter and unknowingly cover the new rosettes and they starve. Don’t add new mulch to L. cardinalis at this time of year. Instead, look for the new rosettes and remove mulch and debris that cover them. You don’t have to remove mulch from around them, just make sure the new leaves can get sunlight.

Debris is only the first hurdle to jump when trying to cultivate this native in your own gardens. This species self-sows only in moist soil. In Kentucky, that can spell a bit of trouble for gardeners because about the time this flower goes to seed, our climate often dries up. Keep the area moist if you want your flowers to reseed.

Never let them dry out for long. They are one of the few natives that will require additional water during hot spells and droughts. In nature, they grow along streams and ponds, and in swamps and wetlands. They prefer lots of sun but will tolerate and even thrive in shade as long as the soil is moist.

Propagation from both seeds and cuttings is easy. Collect seeds after the pods ripen and split, usually three to four weeks after blooming. It’s common for open blooms to persist toward the top of the stalk while pods near the bottom are ready to drop seeds. Take cuttings of two nodes early in the season so they’ll have time to produce a rosette.

Seeds require 60 days of cold moist stratification. Like many species with small seeds, they need light to germinate, so sow right on top of loose dirt. The seeds are tiny so it’s difficult to control them while sowing. If a new plant tries to bloom its first fall, clip the stalk to encourage more rosette growth.

To increase the chances that your L. cardinalis returns year after year, plant it in good sunlight, keep the area moist, and keep the bed free of debris once you spot new growth. They will thrive in some shade, as long as the soil is moist. It’s not difficult; knowing what to provide is the key. If you’d like a more reliable lobelia, consider Lobelia siphilitica. Its blue blooms are a true blue, the plant adapts well to most gardens, and hummingbirds like it.

Photo credits: Common license via Biodiversity Heritage Library