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families, including Ophiopogonaceae Macrophytography of Cultivated Liriopogons Endl., Juss., Convallariaceae and Genera Delineation Horan., and currently (Stevens, 2006), Ruscaceae Spreng. Members of liriopogons are dif- Paul R. Fantz1,2 ficult to segregate and identify by many professionals in the nursery and landscape industries. They typi- ADDITIONAL INDEX WORDS. Liriope, , Convallariaceae, Haemodoraceae, Liliaceae, Ophiopogonaceae, Ruscaceae, morphology, ground covers, aztec grass, cally use only a few characters for lilyturf, mondo grass, monkey grass, snakesbeard segregation of species: growth form (‘‘clumper’’ vs. ‘‘runner’’), height, SUMMARY. Liriopogons (Liriope Lour. spp. and Ophiopogon Ker-Gawl. spp.) are length and width, and flower color. versatile landscape with a complexity of taxonomic problems, including These traits are variable when one the question of whether they are segregate genera or only one . examines named plants. Hence, com- Macrophytography (descriptive terminology of morphology) of the liriopogons is described with commentary on patterns of variation and reliable characters for mon or vernacular names used for segregation. Liriopogons were found to include two valid genera, delineated and these plants typically are associated described, and two imposters marketed as liriopogons. Liriope species bear across generic lines. One needs to spreading to upright rotate flowers with zygomorphic , of which the clearly define and understand filaments are sigmoid, the anthers oblong and poricidal dehiscent, and the style is characteristics exhibited and their incurved-falcate. Ophiopogon species bear nodding campanulate flowers with patterns of variation before one can actinomorphic stamens, of which the filaments are subsessile and straight, the use those characters that are distinct anthers sagittate and longitudinally dehiscent, and the style is straight. The and reliable for distinguishing genera imposters are nonvalid liriopogons, and include species of sedges and grasses segregation, delineation, and accurate misidentified as liriopogons. Included are a key to delineation of taxa and a table identification of plants used in molec- of taxonomic terminology used in this study for describing liriopogon taxa. ular research projects. Phytography is the descriptive iriopogons are versatile land- Liriope and Ophiopogon were terminology (morphology) of plants scape plants that are becoming united under the genus Ophiopogon and their component parts for the Lincreasingly important in the (Maximowicz, 1781), as distinguish- purpose of providing an accurate nursery and landscape industries ing features were limited. L.H. Bailey and complete vocabulary for descrip- (Adams, 1989). Liriopogons are discussed the complex nomenclatural tions, identification, and classification commonly known as ‘aztec grass’, history and was unsure if there were (Radford et al., 1974). Macrophytog- ‘lilyturfs’, ‘mondo grass’, ‘monkey two distinct genera or one genus as raphy includes structures one can grass’, or infrequently as ‘snake- treated by botanists in the 1800s observe with the naked eye, hand beards’ in the green industry trade (Bailey, 1929). However, he did not lens, or a low-powered microscope (Fantz, 1993). A complexity of taxo- merge them, but recognized two gen- (·10 to ·30). nomic problems were reported that era of cultivated liriopogons as Liriope A taxonomic program was initi- needed to be resolved in cultivated and Mondo (Kaempf.) Adanson (Bailey, ated at North Carolina State Univer- liriopogons (Fantz, 1993). How can 1929). Currently, Ophiopogon is a sity with the objective of a taxonomic one segregate species and ? conserved name recognized interna- revision to include an inventory of Are liriopogons members of one tionally over the name Mondo. Mod- cultivated germplasm, quantitative genus or two genera (Ophiopogon ern authors have followed Bailey’s descriptions of taxa, observational and Liriope)? The latter question treatment of two genera, including notes, nomenclatural comment, needs to be resolved first to begin the official reference of the American documented vouchers, and identifi- addressing the previous question. Society for Horticultural Science for cation aids (e.g., keys). In the green correct scientific names (Griffiths, industry today, there are four distinct Salary and research support provided in part by the 1994). However, recent molecular genera sold as liriopogons! The North Carolina Agricultural Research Service research is leading to conclusions that objectives herein were to define the (NCARS), Raleigh, NC 27695-7643. Additional funds in support of research provided by Taylor’s support only one genus, not two phytography, to discuss the morphol- Nursery, Inc. (Raleigh, NC) and publication funds (Cutler, 1992; Mcharo et al., 2003; ogy of liriopogons and patterns of provided by the North Carolina Association of Nurs- Rudall et al., 2000). erymen, Inc. (Raleigh, NC). variation observed, to determine the Ophiopogon was placed originally number of liriopogon genera, and to Thanks go to Paul Lineberger, retired Superintend- ent, Horticultural Field Laboratory, Raleigh, and his in the Haemodoraceae Arnott note those characters that are being staff for cultural assistance with germplasm collection (Bentham and Hooker, 1880). Later, used in developing quantitative used in this study, and to those individuals, nurseries, the genus was transferred to several and botanical gardens listed in Table 1 that donated descriptions of the taxa. plants for this research. The use of nursery and trade names in this publication does not imply endorsement by the NCARS of the nurseries or products named nor criticism of similar ones not mentioned. Units 1Department of Horticultural Science, North Caro- To convert U.S. to SI, To convert SI to U.S., lina State University, Raleigh, NC 27695-7609 multiply by U.S. unit SI unit multiply by 2Corresponding author. E-mail: paul_fantz@ 2.54 inch(es) cm 0.3937 ncsu.edu. 25.4 inch(es) mm 0.0394

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Materials and methods plants have elongate , leav- Table 1. Sources of liriopogon Germplasm of liriopogons culti- ing open patches between plantlets. germplasm, including the original origin as cited by the source. vated in the United States were accu- These members are typically vigorous mulated, grown together from 1990 growers, becoming aggressive in Botanic gardens/arboreta to 2005 for morphological compar- landscapes, and appearing weedy. Brookside Gardens, Wheaton, MD ison and observation, and vouchered Weakly rhizatomous plants have short Busse Gardens, Cokato, MN as described by Fantz (1994). Table 1 runners, with daughter plants borne Carroll Gardens, Westminster, MD summarizes the sources of germplasm close to the mother plant and their Duke Botanic Gardens, Durham, NC collections reported (Fantz, 1994), intertwining. This growth pat- Hangzhou Botanical Garden, Hangzhou, China and includes the known original tern will form a dense carpet or mound over the ground with age, JC Raulston Arboretum, North Carolina source of origin of some taxa being State University, Raleigh, NC introduced into the U.S. from China, with original planting sites merging together, providing an attractive Millpond Plantation, Thomasville, GA England, Germany, and Japan. Table Royal Botanic Garden, Kew, UK ornamental appearance. These plants 2 summarizes the morphological U.S. National Arboretum, characters from which data were commonly are cited as stoloniferous Washington, DC obtained for each taxon examined. in the literature, but stolons are Nurseries/garden centers Table 3 provides the phytographic defined historically as specialized hor- Bentley Nursery, Monticello, FL descriptive terminology used by this izontal stems that creep along the Kurt Blumel, Inc., Baldwin, MD author and others (Bagust, 1992; ground on the soil surface, not Classic Groundcovers, Athens, GA Dahlgren and Clifford, 1982; Dahlg- beneath it (Harris and Harris, 1994; Coastal Gardens and Nursery, Myrtle ren et al., 1985; Harris and Harris, Radford et al., 1974). Beach, SC 1994) that follows standard taxo- Caespitose plants expand out- Fowler’s Nursery, Raleigh, NC Evergreen Nursery, Athens, GA nomic references. ward radially from the caudex crown of the original plant in dense tufts Garden Place, Mentor, OH Results and discussion (‘‘clumper’’), forming a mound or Ga¨rtnerischer Pfanzenbau, cushion on the ground with age. Marktheidenfeld, Germany Results obtained and the follow- Greenbrier Farms, Chesapeake, VA ing discussion will be presented in five The mound includes the original Hines Nursery, Fulchear, TX parts. First, phytography of liriopo- ‘‘mother’’ plant from which lateral Ishiguro Momiji-en, Santa Rosa, CA gon morphology and patterns of var- secondary plantlets (‘‘daughter plants’’) Juroku-en, Kasugahara, Japan iation are discussed, organ by organ. produce new clumps of and Kairyo-en, Kawagochi, Japan Second, characters reliable for genera scapes. Individual mounds are quite K-Mart, Cary, NC and species segregation are presented. distinguishable after several years Louisiana Nursery, Opelousas, LA Third, the number of liriopogon of growth. Individual plants are Malloy Nursery, Monticello, FL genera are discussed. Fourth, discus- crowded together, thus it is difficult McDonald Garden Center, sion is presented on five common to observe soil patches between them Hampton, VA names used for liriopogons in the as with rhizatomous plants. Micro Macro International, Rarely, one will encounter a non- Windemere, FL green industry. And fifth, a key is Plant Delights Nursery Inc., presented to the cultivated genera acaulescent growth form. One species was stoloniferous, bearing several Raleigh, NC that are sold as liriopogons along Powell Gardens, Princeton, NC with generic descriptions of the true short decumbent stems creeping on Riegel Plant Company, liriopogons. the ground with ascending branches. Experiment, GA Another species was aboreal with Shady Oaks Nursery, Waseca, MN Phytography. leaf-bearing erect and branching Southern States Nursery, Liriopogons are herbaceous per- aboveground. MacClenny, FL ennials. Those cultivated in the east- ROOTS. Roots typically were dif- Spring Hill Nursery, Peoria, IL ern United States are primarily ficult to voucher, because damage Swift Creek Nursery, Clayton, NC acaulescent, bearing a basal occurring as plantlets were excavated Taylor Nursery, Raleigh, NC of grass-like leaves from a subterra- from field plantings. However, Terra Nova Laboratories, Portland, OR nean stem. The leafless, flower-bear- vouchers of greenhouse-grown plants Thomasville Nurseries, ing scape is the only erect ‘‘stem-like’’ in containers provided data. Thomasville, AL structure. Caulescent members are Most liriopogons produce fibrous Tidwell Nursery, Atlanta, GA Andre Viette Perennials, Fisherville, VA rare, and typically are not available roots with threadlike segments of Wal-Mart, Clearwater, FL currently in the commercial green equal thickness (0.5–2 mm in diame- Willis Nursery Company, Ottawa, KS industry. ter). Primary segments are elongated Windmill Farms, Sebring, FL GROWTH FORM. Most plants are and stramineous (straw-colored, a Individuals rhizatomous (‘‘runner’’), sending out dull brownish-yellow), and produce Paul Aden, Long Island, NY specialized stems (rhizomes) from scarce secondary rootlets. A few pro- Leo Ammon, Bosman, MD the caudex of the mother plant just duce secondary and tertiary rootlets. Tony Avent, Raleigh, NC beneath the soil. Rhizomes end in a Some primary segments bear occa- Edith Eddleman, Durham, NC daughter plant growing upright sional tuberoids (nodules), a swollen Richard Hartledge, Raleigh, NC through the soil and this stem deteri- area that resembles a tuber. Paul Jones, Durham, NC orates with age, breaking off from the Mularoni and Anderson (1987) Clarence Landis, Spanish Fort, AL mother plant. Strongly rhizatomous reported these nodules as repositories Alex Summers, Bridgeville, DE

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Table 2. Morphological characters examined for determining the diagnostic features of liriopogons and segregating taxa. Measurements were obtained in metric units (1 cm = 0.3937 inch, 1 mm = 0.0394 inch). Scapes Growth form Number Color Plant height (centimeters) Length (centimeters) Type Spread diameter (centimeters) Location Number per fascicle Runner length (centimeters) (millimeters) Internode length (centimeters) Length (centimeters) Stems Diameter (millimeters) Length (millimeters) Type Color Width (millimeters) Length (centimeters) Shape Tube (millimeters) Diameter (millimeters) Perigone (millimeters) Rachis Roots Length (centimeters) Stamens Type Diameter (millimeters) Type Length (centimeters) Color Filament (millimeters) Diameter (millimeters) Shape Filament color 2 length (millimeters) Number of fascicles Anther length (millimeters) Internodes (millimeters) Anther color Nodules Cockscomb Dehiscence Shape Fasciation Number Branching Pistil Length (millimeters) Style length (millimeters) Diameter (millimeters) insertion Length (millimeters) Ovary height (millimeters) Leaves Width (millimeters) Length (centimeters) Shape Width (millimeters) Color Margin Foliar bracts Shape Midrib elev. Length (millimeters) Diameter. (millimeters) Number of. veins Width (millimeters) Number per Apex Shape Texture Color Color Curvature Pedicels Diameter (millimeters) length (millimeters) Variegation Fruit length (centimeters) Color Shape Location Color Band type Band width (millimeters)

(or storage organs) of a major energy grow upward with leaves attached growing upward and fibrous roots source accumulated over a period of basally. The lower portion of the growing downward. Rhizomes grow time, and erroneously called a ‘‘tuber caudex produces roots that grow out- laterally, away from the mother plant root.’’ A few members did produce a ward and down. Vouchering of cau- just below the soil, often becoming thickened fleshy root (2–4 mm in dexes in older plants became difficult intertwined with other underground diameter). Primary segments were because of their thickness, which rhizomes in the colony as well as with elongated, dull whitish, and lacked required a spade, knife, or axe to their roots. Rhizomes often break smaller rootlets. slice through. Pulling up daughter apart when one digs up a plant, as STEMS. Liriopogons exhibit sev- plants often resulted in the younger they deteriorate with age. Rare stem eral stem types. The thickened, sub- breaking off from the mother types include decumbent stems laying terranean, woody-like caudex is much plant. along the ground surface and erect longer than wide, seemingly devoid Most members produce elon- stems that have sparse branching. of leaves, with inconspicuous nodes. gate, narrowly cylindrical rhizomes LEAVES. Liriopogon leaves are Caudexes are oriented vertically to with prominent nodes bearing sessile, evergreen, simple, sessile, distichate, oblique within the soil. New clasping, appressed, ascending, imbri- basically linear with a gradual tapering are produced from lateral buds in cated, oblong-deltoidal leaves. New toward the apex, and a less prominent the upper lateral portion (crown) of plantlets are produced at the rhi- taper toward the base. The margins the caudex that quickly bend and zome’s tip with grass-like leaves and some veins produce microscopic

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Table 3. Terminology used in describing the morphology of liriopogons. Measurements used are in metric units (1 mm = 0.0394 inches) and standard taxonomic format (x-y is common measurement range). Characteristics and definitions General terms Abaxial: lower surface, the side away from the axis. Acuminate: a prolonged pointed apex, tapering concave curved. Acute: a pointed apex, tapering straight. Adaxial: upper surface, the side toward the axis. Arboreal: stems above ground are erect. Auricle: small, -shaped basal appendage. Bib: a daughter plant with a few leaves; trade marketing term for sale of individual, daughter, liriopogon plants. Complicate: folded. Decumbent: prostrate stem creeping along the surface of the ground. Glabrous: lacking hairs; glabrate is nearly hairless. Liriopogon: general term applied to grass-like plants of the genera Liriope and Ophiopogon. Naviculate: surface bears a keel like a boat. Phytography: general term for descriptive terminology (morphology) of plants and their component parts. Pubescent: hairs present. Sessile: stalkless. Taxon: a recognizable taxonomic entity with rank not designated, such as a genus, species or Translucent: almost transparent structure. Growth forms Acaulescent: plants bear a basal rosette of leaves from a subterranean stem (stemless aboveground). Arboreal: plants bear erect stems above the ground. Caespitose: plants expand outward radially from crown of subterranean stem in dense tufts forming a mound or cushion on the ground. Decumbent: plants bear several short stems reclining on the ground with apex and lateral branches erect. Rhizomatous: plant bears a subterranean stem (caudex) with propagative shoots (rhizomes) sent out that culminate in a daughter plant; often cited as stoloniferous in literature. Stoloniferous: plant bears a decumbent creeping stem along the ground surface that produces a daughter plant at its tip. Roots Fibrous: numerous, filamentous (threadlike) roots, 0.5–2 mm diameter Fleshy: roots few, thickened, 2–4 mm diameter Tuberoids (nodules): swollen segment areas of roots that resemble a tuber. Stems Caudex: a short, thickened, vertical, perennial, subterranean stem with daughter plants produced laterally from the caudex. : thickened, subterranean, woody-like stem with inconspicuous nodes, leaves appressed, inconspicuous, deteriorating quickly leaving veins. Leaves Appressed: leaves lay flat against stems (on stolons). Broad leaf: leaves typically 7–13 mm wide. Clasping leaf: base of the blade wraps around the stem. Deltoid: leaves are triangular-shaped. Distichous: leaves are two-ranked along the stem. Imbricate leaves: leaves overlap each other. Medium leaf: leaves are typically 5–8 mm wide. Mini leaf: leaves typically 3–5 mm wide. Narrow leaf: leaves typically 1–3 mm wide. Petiolate: leaf blade bears a stalk. Pliable leaf: leaves easily bent or folded upon itself by man, exhibiting minimal damage. Rigid leaf: leaves thick-textured, resist bending or folding upon itself by man, and typically tear at folding point. Wide leaf: leaves are typically 12–23 mm wide. Transverse variegated leaf: leaves bear transverse yellowish zones deficient in . Tristichate: leaves three-ranked on stem. Variegated leaf: leaves bear longitudinal bands the length of the leaf deficient in chlorophyll and appearing yellow to greenish-yellow to cream to silvery. Inflorescence : modified leaf-like structure subtending a flower, borne at base of pedicel. Branched rachis: rachis branching above, appearing panicle-like; panicle of dichasia. Cockscomb: general term to a rachis expanding laterally and flattening near the apex. (Continued on next page)

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Table 3. (Continued) Terminology used in describing the morphology of liriopogons. Measurements used are in metric units (1 mm = 0.0394 inches) and standard taxonomic format (x-y is common measurement range). Characteristics and definitions Congested fascicles: fascicles borne close together with short rachis internodes. Cymose: reference to a determinate inflorescence that is a compound dichasia or cyme. Dichasium: type of determinate inflorescence that produces three flowers, the terminal flower opening first. Fasciation: general term referring to a cockscomb bearing two to several axes bearing flowers from the cockscomb apex. Fascicle: clusters of flowers or fruit borne laterally from the rachis. Foliar bract: elongated, leaf-like bract, borne early in season only at the lowest fascicles. Inflorescence: a flowering branch; also used herein for a fruiting branch. Loose fascicles: fascicles spaced apart with long rachis internodes, particularly at lower to middle rachis nodes. Pedicel: stalk of the flower or fruit, measured from the node to the flower base. Peduncle: stalk of the inflorescence, measured from the base to the node bearing the first buds, flower or fruit. Plano: peduncles that are flattened in cross-section. Raceme: an elongated axis bearing pedicillate or stalked flowers. Rachis: term for the portion of the inflorescence axis from which flowers and fruit are borne. Scape: general term for an inflorescence borne from an acaulescent plant; leafless inflorescence. Spike: an elongated axis bearing sessile flowers. Striae: fine raised lines (= veins) on the scape axis. Terete: peduncles that are nearly round in cross-section. Flowers Actinomorphic: radial symmetry. Androecium: collective term for the stamens. Anther: sac in a borne at the apex of the filament. : an undeveloped flower. Campanulate: bell-shaped flowers. Carpel: portion (chamber) of a compound pistil formed from one modified leaf; megasporophyll. Extrose: turned outward, away from the structure; applied to stamen orientation. Filament: stalk of the stamen. : collective term for the female reproductive organ (pistil). Hemiperigynous ovary: subinferior ovary, other floral parts fused basally with ovary and free parts forming whorls around the ovary. Hypogynous ovary: superior ovary, ovary borne above insertion of other floral parts. Ovary: expanded basal portion of pistil that bears the ; becomes fruit at maturity. Perianth: general term that includes and collectively, the floral envelope. Perigone: fused perianth tube that narrows abruptly into a prolonged basal projection. Petals: the inner of the perianth. Pistil: female reproductive organ of a flower, comprised of a basal ovary, a style, and the terminal . Rotate: flowers with a short tube, lobes abruptly spreading, appearing star-shaped. Sepals: the outer whorl of the perianth. Sigmoid: S-shaped; applied to shape of filament. Stamen: male reproductive organ in a flower, comprised of a filament and an anther. Stigma: terminal portion of pistil that is receptive to pollen. Style: narrow portion of pistil connecting stigma to the ovary. Suture: the line of dehiscence in the anther. Zygomorphic: bilateral symmetry. Fruit : feshy fruit developing from a single pistil and bearing several seeds. : a dry, dehiscent fruit comprised of more than one carpel. Drupe: a fleshy, indehiscent fruit developing from a single pistil with a stony endocarp surrounding a single . Testa: the seedcoat.

hyaline teeth that are discernable to Liriopogons leaves are glabrous. Tristichate leaves belong to sedges the touch as one moves their fingers One can purchase plants labeled as a that seeded in and outgrew the lirio- downward toward the base. Leaves liriopogon that has leaves distichate pogon, or a sedge misidentified and superficially resemble leaves of grasses and pubescent intermingled with gla- marketed as a new liriopogon. and sedges, hence are referred to in brous leaves. These pubescent leaves All liriopogons produce a trans- the literature as ‘‘grass-like’’ leaves. belong to grasses that germinated lucent, thin-texture lateral sheath on One species is unique with a rapid from seeds, and grew as weeds in each side of the leaf at its base. This basal reduction in leaf width to amongst the liriopogons. Rarely, sheath is wrapped around other leaves exhibit a ‘‘,’’ a rare trait in one can purchase plants labeled as a and quickly deteriorates and shreds liriopogons. liriopogon with tristichate leaves. as leaves mature. Commonly, the leaf

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base between the lateral sheaths is their widths are variable in some later in the flowering season. The scarcely pigmented with chlorophyll, selections, more constant in others. rachis is erect on the peduncle in some but becomes prominently yellowish- Juvenile variegated leaves are yellow members and slightly to prominently orange in a few members. (‘‘golden’’) to greenish-yellow, fad- oblique in other members. The rachis Leaf veins are parallel, longitudi- ing to cream to off-white (‘‘silvery’’) decreases in diameter from the base to nal, darker green, and thickened, and with age. The brightness/dullness of the apex, green in the juvenile state, are asymmetrical in number on either the colors can very between cultivars, and pigmented from the base upward side of the midrib. The midrib is as well as within a cultivar, depending as flowering progresses. Often, the raised minutely on the adaxial surface upon the plant’s age and environ- apex is whitish to light pigmented, in some members, impressed in mental parameters. Horizontal varie- leading individuals to interpret the others. The abaxial surface varies in gated bands are rare, but do occur, darker pigmented flowers (violet) as degrees of glaucousness between and they vary in width and often are lighter in hue (bluish-violet or veins. Species appear to be consistent irregular in outline (jagged and light- lavender). Typically, the rachis is in the amount of glaucousness, but ning bolt-like in appearance). unbranched, but occasionally, the interpretation is subjective. Leaf width can be divided into lower portion will exhibit a lateral Leaf texture is very subjective in five artificial categories that can be branch, a random character occurring interpretation. Most liriopogons have useful in cultivar descriptions. These within cultivar selections. A com- pliable, very thin leaves that grow are designated as narrow (1–3 mm), pound rachis exhibits a panicle of upward and arch outward, often exhi- mini (3–5 mm), medium (5–8 mm), dichasia, the rachis branching consis- biting a broad inverted U-shape such broad (7–13 mm), and wide (12–23 tently along most its length, lateral that the leaf apex is oriented down- mm) widths. Leaves produced later in lengths shortening upwards, and ward. Arching occurs somewhere the season are stunted in growth, up appearing pyramidal to cone-shaped between one-third and three-fourth’s to 80% shorter than the length of (e.g., ‘Christmas ’). Some culti- of the leaf’s length. Thicker-textured other leaves. Liriopogons grow larger vars exhibit cockscombs, the rachis leaves are erect with little arching near over several years and length meas- becoming flattened and broad, which their tips, often exhibiting an inverted urements will increase slightly for increases the number of fascicles and J-shape such that the apex is oriented several seasons. flower production. This trait is laterally. These leaves are rigid, resist . Commonly, regarded as unique and more orna- bending, and are difficult to fold, the scape is described as a raceme or mental. Fasciation is associated with tearing at the point of the fold. spike, which is an oversimplification. some cockscombs, the apex produc- Liriopogon leaves are typically Liriopogons produce a compound ing two to several erect axes bearing medium to dark green on the upper inflorescence consisting of a raceme flowers. Both of these branching surface, and lighter beneath. Atypical with the rachis bearing fascicles of traits are variable each season in the colors are valued ornamentals. Black dichasia to compound dichasia (cym- degree of production in a taxon. mondo grass is a liriopogon noted for ose). Scapes produced later in the Fascicles are arranged spirally on its very dark reddish-purple to black- flowering season have shorter the rachis and vary in number pro- ish leaves. Some cultivar selections peduncles, some remarkably so, duced. The fascicles are clusters of hold the darker color well. Others because of a shorter time for optimal dichasia along the rachis, producing will produce green foliage on daugh- growth. Some bibs (a trade term for a three flowers per fascicle, the central ter plants after several years of age, young, individual daughter plant) one opening first, the lateral pair then resemble creeping lilyturfs in take 1 to 4 years to bloom. Some taxa opening later. Compound dichasia appearance. Liriope ‘Silver Dragon’ will bloom infrequently, only once or produce clusters of three to seven is noted for its leaves that are nearly twice in a decade. Generally, older flowers per fascicle. Congested fas- all silvery-white, some which bear plants will produce more scapes in cicles are crowded close together with longitudinal bands of green. Some successive years than younger plants. short internodes, whereas loose fas- older selections produce daughter Peduncles elongate rapidly and cicles are separated by longer intern- plantlets with all green foliage. Liriope exhibit two types. Terete peduncles odes, particularly in the lower portion ‘Peedee Ingot’ is one member pri- are nearly round in cross-section, of the rachis. zed for its consistent golden-yellow often weakly compressed laterally, Pedicels are subquadrangular foliage. with a strong striate ridge on two and often pigmented. They may twist, Variegated members as orna- sides with several smaller striae be- causing flowers to appear nodding. mentals are valued, lumped together tween. Diameter is consistent nearly Pedicels are consistent in length with by growers and landscapers under throughout its length. Typically, flowers, but elongate to a new con- the generic term ‘Variegata’ or rec- these peduncles are green (sometimes sistent length with fruit. ognized more recently by a number of becoming purplish) as flowering Bracts are borne at the base of distinct names. Variegated areas in occurs, and become brownish as fruit the pedicels and are arranged in two the leaf commonly occur in longitu- develop. Plano peduncles are flatter in series. The outer bract is conspicuous, dinal bands. Some cultivars have cross-section, commonly narrow and larger, complicate to naviculate bands restricted to the leaf margin, unpigmented at the base, gradually around the pedicel, the apex acute whereas others exhibit longitudinal widening and becoming pigmented to acuminate, with margins some- bands internally within the leaf that toward the apex. times bearing translucent auricles as alternate with green chlorophyll The rachis develops a consistent observed in the leaves. The inner bands. The number of bands and length range within taxa, early and bract is small, inconspicuous, usually

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perpendicular to the outer bract and appearance of being poricidal. Other States indicates that genera and spe- pedicel. A foliar bract is very distinc- liriopogons bear actinomorphic sta- cies can be segregated accurately. tive, elongated, and leaf-like. It is mens, with subsessile anthers borne in Characters associated with reproduc- gigantic-sized for bracts, occurring a ring around the stigma. Anthers are tive structures were more reliable only in the earliest scape(s) of the yellow, sagittate, and dehisce longi- than those associated with vegetative season, and only from the lowest tudinally along nearly its entire structures for accurate identification. fascicle(s), reducing quickly in size up length. Characters of the inflorescence axis, the rachis to become a ‘‘typical’’ bract. GYNOECIUM. Liriopogon flowers bracts, flowers, stamens, pistil, fruit, FLOWERS. Flowers are of two contain one pistil with six lobes and and leaf venation appear reliable for types. Rotate flowers are erect, star- one central style that may be shorter segregation of genera. Species can be shaped, project outward or slightly than, subequal, or longer than the segregated by a combination of mul- upward in orientation, and exhibit stamens. tiple vegetative and floral characters, the stamens and pistil conspicuously. There are two distinct types. but will require plants to be in the Campanulate flowers nod from Some liriopogons have hypogynous floral state for accurate identification. twisted pedicels borne on an oblique ovaries with the style incurved-falcate, Leaf lengths must come from ma- rachis, hiding the stamens and pistil cylindrical, and bearing a diffused tured leaves late in the season. from view until one reorients the stigma of papillae. Other liriopogons Leaf widths can be quantified, a flower manually. Flowers are white have hemiperigynous ovaries with the useful trait for cultivars and some or bear hues of anthocyanin pig- style straight, tapering slightly from species. Foliar bract lengths must ments. Buds exhibit pigmented hues the base to apex, and bearing a trifid come from the earliest-produced before opening. Pigmentation, even (three-lobed) stigma. scapes. Peduncle lengths must come within cultivars, will vary in hues from FRUIT. Historically, descriptions from scapes produced in early to year to year and within a season, thus of fruit vary and are described as a midseason. Flower color varies in it is difficult to interpret or quantify berry (Bailey, 1929), a drupe (Hume, hues within and between seasons, by standardized color charts. This 1961), berry-like (Huxley et al., and thus are less reliable, even in trait presents problems in quantifying 1992), or as a leathery capsule ruptur- cultivars. Thus, standardized color flower colors in cultivars. ing early to expose the seed chart values loose their value in floral Liriopogons produce a perianth (Cutler,(1992). Anatomical studies descriptions. Fruit production varied of petals and petaloid sepals fused indicate that the pistil of liriopogons somewhat between seasons, lacking basally, with conspicuous free lobes splits irregularly, but more or less in some years. Several named species above. Some plants exhibit little transversely in the postfloral stage to survived vegetatively for more than fusion, and the perianth appears free expose developing seeds (Dahlgren one season, but never produced nearly to the base. Others exhibit a and Clifford, 1982). The exposed scapes. Thus, these taxa were more perianth with a distinct broadened, seed with the testa (seedcoat) would difficult to segregate. campanulate tube that occasionally then provide the color. narrows abruptly into a prolonged One species was emphasized as Number of liriopogon genera. basal ‘‘perigone’’ that mimics the unique in bearing up to six fruit per There are four genera sold as pedicel in appearance. Flowers will pedicel, whereas other species typi- liriopogons in the trade. Two genera dehisce at the joint between the ped- cally produced one (Hume, 1961). are imposters—misidentified sedges icel and perigone. Perianth lobes are Hume’s conclusion was based on a ( L., Kyllinga Rottb., Cyper- similar in length with the free small sample size studied. Plants in aceae Juss.). I had been informed over lobes typically about 0.5 mm nar- this study regularly produced one to the years from liriopogon growers rower than lobes. Some mem- four fruit per pedicel, or occasionally that some nurserymen in the eastern bers exhibit a narrow rim (0.1–0.5 six fruit per pedicel. Many cultivars United States were unable to distin- mm) along the edge of the perianth lacked fruit or were sparsely fruited. guish liriopogons from grass-like inner lobe’s surface that lacks pig- The fruit was berry-like, subglobular weeds, marketing the weeds as lirio- mentation, making the flower’s pig- to ovoid fruit with a leathery wall that pogons. Twice, I was able to docu- ment appear lighter in color. The remained intact, not rupturing early ment this rumor. In June 1995, a perianth is persistent during early to expose the seed. Occasionally, the discount chain in Raleigh, North stages of fruit development, then los- fruit split irregularly to expose one Carolina, was selling Liriope exiliflora ing pigmentation upon drying and seed within that occupied nearly all (L.H. Bailey) H.H. Hume as ‘‘an finally dropping. the space. Fruit of some liriopogons unknown landscape species that ANDROECIUM. Liriopogon an- was purplish-black to black, exposing forms dense mounds of yellowish droecia have six stamens that are free brownish seeds, or greenish-blue to flowers.’’ This imposter was Cyperus, and extrose, but exhibit two distinct blue to bluish-black exposing brown- bought and assigned research num- types. Some liriopogons bear zygo- ish or white seeds. ber 95-242, and vouchered (Fantz morphic stamens, with a conspicu- 5930) for deposit in a . In ous, sigmoid filament that orients Reliable characters for July 1996, a different discount chain the stamens to the lowest side of the segregation. in Clearwater, Florida, was marketing flower. Filaments are pigmented like Examination of a multitude of a liriopogon plant as ‘‘Liriope minor. the perianth. Anthers are yellow, macromorphological characters from New. Fine textured plant. Colonizes oblong, and dehisce only in the upper a wide range of liriopogon germplasm an area readily. Desired for its reduced quarter of the suture, giving them the in cultivation in the eastern United size and miniature .’’ This

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imposter was Kyllinga, bought and Table 4. A comparison of liriopogon genera. assigned research number 96-246, Character Liriope Ophiopogon and vouchered (Fantz 6117). These imposters were rare, but Peduncle type Terete Plano were documented as available in gar- Peduncle diameter Cylindrical, consistent Tapered apex to base den centers and marketed as new and width liriopogon taxa. They bear grass-like Peduncle cross-section Terete Flat leaves and root tuberoids or storage Flower type Rotate Campanulate organs, as do liriopogons. Sedges are Flower orientation Spreading to upward Nodding distinguished by their tristichate Pedicels Straight Twisting (three-ranked) leaves, peduncles tri- Stamens symmetry Zygomorphic Actinomorphic angular in cross-section, branched Filament length Prominent, Inconspicuous, inflorescence rachises, and straw- anthers stalked anther subsessile colored flowers with reproductive Filament shape Sigmoid Straight organs hidden inside bracts. Anther shape Oblong Sagittate Occasionally, one can find a Anther dehiscence Poricidal Longitudinal pot(s) of liriopogon that bears bibs Ovary position Hypogynous Hemiperigynous with distichous (two-ranked) leaves Style length Incurved-falcate Straight and lacking scapes. Leaves are pubes- Style diameter Cylindrical, consistent Tapered base to apex cent and bear a distinct junction (the Stigma Unlobed, diffused Three-lobed ligule) in the leaf between the sheath papillae and the flat blade. These are grasses Fruit Purplish-black to black Blue to bluish-black ( Barnh.), outcompeting the Seeds Brownish Brownish to white liriopogon bibs (individual daughter plants) that died, leaving only the grasses living in pots being marketed. Currently, there are five common those grass-like plants of the genus Other pots bearing the same label names associated with liriopogons. Mondo. The name ‘‘mondo grass’’ has name in garden centers were recog- LILYTURFS. The name ‘‘lily-turf’’ continued to be used and is applied nizable as liriopogon taxa. was coined for all liriopogons based strictly to Ophiopogon. Liriopogons have several charac- upon their low sod-forming or turf- MONKEY GRASS. The origin of ters that come in contrasting pairs or ing plants of the lily family (Bailey, this name is unknown. It is applied two distinct types. When segregated 1929). The hyphen has been elimi- commonly to those liriopogons of and correlated, these distinct types fall nated over time. However, modern both genera with narrower leaves that into two distinct groupings; hence, practice has been to use the name bear inflorescences amongst the evidence that there are two distinct strictly for members of Liriope. Rarely leaves and creeps to form ground genera of liriopogons. Table 4 pro- has the name been associated with colonies. Everyone with whom I have vides reliable characters of segrega- Ophiopogon. discussed the origin of the name tion for Liriope and Ophiopogon. SNAKESBEARD. The generic name monkey grass learned it from other Liriope taxa can be distinguished Ophiopogon (ophio: Greek for snake- individuals using the name. easily by the zygomorphic, rotate like, and pogon: Greek for beard) was The following incident may be flowers borne on terete peduncles, proposed by Ker-Gawl (1821). The irrelevant, but is reported for poten- sigmoid filaments bearing oblong, inflorescence in many species of tial insight on this name’s origin. I poricidal anthers, and a cylindrical Ophiopogon has an obliquely arching was teaching a laboratory class on incurved-falcate style bearing an rachis from which twisted pedicels ornamental plants. The students and unlobed, papillae stigma. The flowers project downward. These scapes I were kneeling beside a massing of open outward to upward, borne on resemble a cobra ready to strike, with the mondo grass, Ophiopogon japoni- straight pedicels. Ophiopogon taxa can the peduncle representing the snake’s cus Ker-Gawl. We were spreading be distinguished easily by the actino- body, the rachis the cobra’s hood and leaves with our hands to locate and morphic, campanulate flowers borne head, and the persistent pedicels the observe the hidden cobalt-blue fruit. on a flattened peduncle, straight fila- beard. An infrequently used name, A homesick Asian student (Thailand) ments bearing sagittate, longitudinal- presumably because Bailey reported observed our actions and became dehiscent anthers, and a tapered that this name ‘‘had no significance to emotional, exhibiting symptoms straight style bearing a three-lobed us’’ (Bailey, 1929). This vernacular associated with suppressed crying. stigma. The flowers are nodding, name has been used strictly with Our actions resembled those of mon- resulting from a twisted pedicel. Ophiopogon. keys in his homeland that descend MONDO GRASS. Bailey recog- from to the forest floor, search- Vernacular or common names. nized his second liriopogon genus as ing patches of grassy leaves for edible Liriopogons cultivated in west- Mondo (Bailey, 1929). Later, the to eat. To this Asian student, ern countries lacked a vernacular or an generic name Ophiopogon was con- we were those monkeys! English name (Bailey, 1929). A his- served over the generic name Mondo AZTEC GRASS. ‘‘Aztec grass’’ is a torical practice has been to use the as the for the genus name used infrequently for a group of generic name as a common name (by international rules). The name variegated Liriope (not cold hardy) in when a vernacular name is lacking. ‘‘mondo grass’’ came into use for the lower south with broader leaves

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RESEARCH REPORTS

Key to genera of cultivated liriopogons Fantz, P.R. 1993. Taxonomic problems in cultivated liriopogons. HortTechnol- Imposters are included in the key to assist those in their identification. True liriopogons ogy 3(2):146–150. are represented in couplet number 3 only. Table 4 provides additional characters for comparison. Fantz, P.R. 1994. A taxonomic re- 1. Leaves three-ranked, sheaths closed; peduncles triangular search update of cultivated liriopogons. HortTechnology 4(1):46–48. (nonliriopogons)...... Sedges 1. Leaves two-ranked, sheaths open. Griffiths, M. 1994. Index of garden 2. Stamens and pistils enclosed in bracts; leaves commonly pubescent, bearing a plants. Timber Press, Portland, OR. ligule at the junction of the sheath with the blade Harris, J.G. and M.W. Harris. 1994. Plant (nonliriopogons)...... Grasses identification terminology: An illustrated 2. Stamens and pistils enclosed in a petaloid perianth; leaves glabrous, lacking a glossary. Spring Lake Publishing, Spring ligule ...... Liriopogons Lake, UT. 3. Stamens zygomorphic; filament conspicuous, sigmoid (s-shaped); anthers Hume, H.H. 1961. The Ophiopogon-Lir- oblong, dehiscence poricidal; style incurved-falcate, cylindrical; stigma iope complex. Baileya 9:135–158. papillate; perianth inserted below the ovary; flowers erect to spreading, rotate ...... Liriope Huxley A., M. Griffiths, and L. Margot 3. Stamens actinomorphic; filaments inconspicuous; anthers saggittate, (eds.). 1992. The new Royal Horticul- dehiscence longitudinal; style straight, gradually tapering to the apex; stigma tural Society dictionary of gardening. trifid; perianth fused to basal portion of ovary; flowers nodding, Macmillan, London. campanulate ...... Ophiopogon Ker-Gawl, J.B. 1821. Ophiopogon spicatus. blue-flowered snakesbeard. Edward’s Botanical Register Table 593. and elongated inflorescences. The cent leaves with ligules, flowers enclosed Maximowicz, C.J. 1781. Ophiopogonis origin of the name is unknown. All in straw-colored bracts, or triangular species in herbariis Petropolitanis servatas plants obtained for this research study scapes and leaf arrangements. exposuit. Bulletin de l’acade´mie impe´riale with the vernacular name of aztec des sciences de Saint-Pe´tersbourg 15:83– grass were Ophiopogon, not Liriope. 90. This included the typical selections Literature cited with elongate leaves and inflorescen- Mcharo, M., E. Bush, D. La Bonte, C. Broussard, and L. Urbatsch. 2003. Mole- ces and dwarf selections of aztec grass Adams, G. 1989. Great ground covers. Amer. Nurseryman 170(8):83–91. cular and morphological investigation of sold under the name Liriope. ornamental liriopogons. J. Amer. Hort. Bagust, H. 1992. The gardener’s diction- Sci. 128(4):575–577. Conclusion ary of horticultural terms. Cassell Publish- One cannot rely only on names ers, London. Mularoni, T. and C.E. Anderson. 1987. found upon plant labels as accurate Growth of Liriope in response to Bailey, L.H. 1929. The case of Ophiopo- various temperature, photoperiod and identifications, as many liriopogons gon and Liriope. Gentes Herbarum nutrient combinations, p. 37–49. In: Phy- sold are misidentified to genus. 2(1):3–37. totron report. North Carolina State Uni- Researchers will obtain misleading versity Press, Raleigh, NC. results when they rely on the names Bentham, G. and J.D. Hooker. 1880. Genera plantarum. Volume III. Reeve, Radford, A.E., W.C. Dickison, J.R. of plants obtained in the trade as an London. accurate source of segregation of lir- Massey, and C.R. Bell. 1974. Vascular Cutler, D.F. 1992. Vegetative anatomy of plant systematics. Harper & Row, New iopogon taxa. Results based upon York. misidentified research samples will Ophiopogoneae (Convallariaceae). J. lead to incorrect conclusions. There Linnean Soc. Bot. 110:385–419. Rudall,P.J.,J.G.Conran,andM.W. are two distinct genera of cultivated Dahlgren, R.M.T. and H.T. Clifford. Chase. 2000. Systematics of Ruscaceae/ liriopogons, Liriope and Ophiopogon, 1982. The : A compara- Convallariaceae: A combined morpholog- in the eastern United States that can tive study. Academic Press, London. ical and molecular investigation. J. Lin- nean Soc. Bot. 134:73–92. be distinguished accurately to genus Dahlgren, R.M.T., H.T. Clifford, and when flowers are present. Occasion- P.F. Yeo. 1985. The families of the Stevens, P.F. 2006. Angiosperm phylog- ally, one will encounter pots labeled monocotyledons: Structure, evolution eny website. Version 7. 28 May 2006. as a liriopogon, but these are impost- and . Springer-Verlag, New .

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