| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| LYSI | Lycopodium sitchense Rupr. | Sitka clubmoss | Lycopodiaceae
|
| LYSU | Lycopodium sulcinervium Spring | Huperzia sulcinervia | Lycopodiaceae
|
| LYTA | Lycopodium taxifolium Sw. | Huperzia taxifolia | Lycopodiaceae
|
| LYTE3 | Lycopodium tenuicaule Underwood & Lloyd | Huperzia tenuicaulis | Lycopodiaceae
|
| LYTRB | Lycopodium tristachyum Pursh var. boreale Victorin | Lycopodium zeilleri | Lycopodiaceae
|
| LYTRH | Lycopodium tristachyum Pursh var. habereri (House) Victorin | Lycopodium habereri | Lycopodiaceae
|
| LYTRL | Lycopodium tristachyum Pursh var. laurentianum Victorin | Lycopodium habereri | Lycopodiaceae
|
| LYTR | Lycopodium tristachyum Pursh | deeproot clubmoss | Lycopodiaceae
|
| LYVE2 | Lycopodium venustulum Gaud. | hairtip clubmoss | Lycopodiaceae
|
| LYVE3 | Lycopodium verticillatum auct. non L. f. | Huperzia acerosa | Lycopodiaceae
|
| LYWI | Lycopodium wilsonii Underwood & Lloyd | Huperzia wilsonii | Lycopodiaceae
|
| LYZE | Lycopodium �zeilleri (Rouy) Greuter & Burdet | | Lycopodiaceae
|
| LYCOP2 | Lycopodium L. | clubmoss | Lycopodiaceae
|
| LYAR | Lycopsis arvensis L. | Anchusa arvensis | Boraginaceae
|
| LYAML | Lycopus americanus Muhl. ex W. Bart. var. longii Benner | Lycopus americanus | Lamiaceae
|
| LYAMS | Lycopus americanus Muhl. ex W. Bart. var. scabrifolius Fern. | Lycopus americanus | Lamiaceae
|
| LYAM | Lycopus americanus Muhl. ex W. Bart. | American water horehound | Lamiaceae
|
| LYAMP | Lycopus amplectens Raf. var. pubens (Britt.) Fern. | Lycopus amplectens | Lamiaceae
|
| LYAM2 | Lycopus amplectens Raf. | clasping water horehound | Lamiaceae
|
| LYAN3 | Lycopus angustifolius Ell. | Lycopus rubellus | Lamiaceae
|
| LYAS | Lycopus asper Greene | rough bugleweed | Lamiaceae
|
| LYCO7 | Lycopus cokeri Ahles ex Sorrie | Carolina water horehound | Lamiaceae
|
| LYDI6 | Lycopus diantherus Buch.-Ham. ex Roxb. | Mosla dianthera | Lamiaceae
|
| LYEUM | Lycopus europaeus L. ssp. mollis (Kern.) Rothm. ex Skalick� | Lycopus europaeus | Lamiaceae
|
| LYEUM2 | Lycopus europaeus L. var. mollis (Kern.) Briq. | Lycopus europaeus | Lamiaceae
|
| LYEU | Lycopus europaeus L. | gypsywort | Lamiaceae
|
| LYLUA | Lycopus lucidus Turcz. ex Benth. ssp. americanus (Gray) Hult�n | Lycopus asper | Lamiaceae
|
| LYLUA2 | Lycopus lucidus Turcz. ex Benth. var. americanus Gray | Lycopus asper | Lamiaceae
|
| LYLU2 | Lycopus lucidus auct. p.p. non Turcz. ex Benth. | Lycopus asper | Lamiaceae
|
| LYPU3 | Lycopus pubens Britt. | Lycopus amplectens | Lamiaceae
|
| LYRUA | Lycopus rubellus Moench var. angustifolius (Ell.) Ahles | Lycopus rubellus | Lamiaceae
|
| LYRUA2 | Lycopus rubellus Moench var. arkansanus (Fresen.) Benner | Lycopus rubellus | Lamiaceae
|
| LYRUL | Lycopus rubellus Moench var. lanceolatus Benner | Lycopus rubellus | Lamiaceae
|
| LYRU | Lycopus rubellus Moench | taperleaf water horehound | Lamiaceae
|
| LYSE4 | Lycopus sessilifolius Gray | Lycopus amplectens | Lamiaceae
|
| LYSH2 | Lycopus �sherardii Steele (pro sp.) | | Lamiaceae
|
| LYSI3 | Lycopus sinuatus Ell. | Lycopus americanus | Lamiaceae
|
| LYUN | Lycopus uniflorus Michx. | northern bugleweed | Lamiaceae
|
| LYVE4 | Lycopus velutinus Rydb. | Lycopus rubellus | Lamiaceae
|
| LYVIP | Lycopus virginicus L. var. pauciflorus Benth. | Lycopus uniflorus | Lamiaceae
|
| LYVI4 | Lycopus virginicus L. | Virginia water horehound | Lamiaceae
|
| LYCOP4 | Lycopus L. | waterhorehound | Lamiaceae
|
| LYRA | Lycoris radiata (L'H�r.) Herbert | red spider lily | Liliaceae
|
| LYSQ | Lycoris squamigera Maxim. | resurrection lily | Liliaceae
|
| LYCOR | Lycoris Herbert | lycoris | Liliaceae
|
| LYPH | Lycurus phleoides Kunth | common wolfstail | Poaceae
|
| LYSE3 | Lycurus setosus (Nutt.) C.G. Reeder | bristly wolfstail | Poaceae
|
| LYCUR | Lycurus Kunth | wolfstail | Poaceae
|
| LYAS3 | Lyellia aspera (Hag. & C. Jens. in C. Jens.) Frye in Grout | lyellia moss | Polytrichaceae
|
| LYLE | Lyellia lescurii (James) Salm. | Bartramiopsis lescurii | Polytrichaceae
|
| LYELL | Lyellia R. Br. | lyellia moss | Polytrichaceae
|
| LYSP3 | Lygeum spartum Loefl. ex L. | lygeum | Poaceae
|
| LYGEU | Lygeum Loefl. ex L. | lygeum | Poaceae
|
| LYAPT | Lygodesmia aphylla (Nutt.) DC. var. texana Torr. & Gray | Lygodesmia texana | Asteraceae
|
| LYAP3 | Lygodesmia aphylla (Nutt.) DC. | rose rush | Asteraceae
|
| LYAR2 | Lygodesmia arizonica S. Tomb | Arizona skeletonplant | Asteraceae
|
| LYBI | Lygodesmia bigelovii (Gray) Shinners | Stephanomeria exigua ssp. exigua | Asteraceae
|
| LYDI4 | Lygodesmia dianthopsis (Eat. ex King) S. Tomb | Antelope Island skeletonplant | Asteraceae
|
| LYDO | Lygodesmia doloresensis S. Tomb | Dolores River skeletonplant | Asteraceae
|
| LYEN | Lygodesmia entrada Welsh & Goodrich | rushpink skeletonplant | Asteraceae
|
| LYEX3 | Lygodesmia exigua (Gray) Gray | Prenanthella exigua | Asteraceae
|
| LYGRA | Lygodesmia grandiflora (Nutt.) Torr. & Gray var. arizonica (S. Tomb) Welsh | Lygodesmia arizonica | Asteraceae
|
| LYGRD | Lygodesmia grandiflora (Nutt.) Torr. & Gray var. dianthopsis (Eat. ex King) Welsh | Lygodesmia dianthopsis | Asteraceae
|
| LYGRD2 | Lygodesmia grandiflora (Nutt.) Torr. & Gray var. doloresensis (S. Tomb) Welsh | Lygodesmia doloresensis | Asteraceae
|
| LYGRE | Lygodesmia grandiflora (Nutt.) Torr. & Gray var. entrada (Welsh & Goodrich) Welsh | Lygodesmia entrada | Asteraceae
|
| LYGRS | Lygodesmia grandiflora (Nutt.) Torr. & Gray var. stricta Maguire | Lygodesmia grandiflora | Asteraceae
|
| LYGR | Lygodesmia grandiflora (Nutt.) Torr. & Gray | largeflower skeletonplant | Asteraceae
|
| LYJU | Lygodesmia juncea (Pursh) D. Don ex Hook. | rush skeletonplant | Asteraceae
|
| LYPA5 | Lygodesmia pauciflora (Torr.) Shinners | Stephanomeria pauciflora | Asteraceae
|
| LYRA2 | Lygodesmia ramosissima Greenm. | Pecos River skeletonplant | Asteraceae
|
| LYRO2 | Lygodesmia rostrata (Gray) Gray | Shinnersoseris rostrata | Asteraceae
|
| LYSP2 | Lygodesmia spinosa Nutt. | Stephanomeria spinosa | Asteraceae
|
| LYTE5 | Lygodesmia tenuifolia (Raf.) Shinners | Stephanomeria minor var. uintensis | Asteraceae
|
| LYTE | Lygodesmia texana (Torr. & Gray) Greene | Texas skeletonplant | Asteraceae
|
| LYTH4 | Lygodesmia thurberi (Gray) Shinners | Stephanomeria thurberi | Asteraceae
|
| LYWR | Lygodesmia wrightii (Gray) Shinners | Stephanomeria wrightii | Asteraceae
|
| LYGOD | Lygodesmia D. Don | skeletonplant | Asteraceae
|
| LYJA | Lygodium japonicum (Thunb. ex Murr.) Sw. | Japanese climbing fern | Lygodiaceae
|
| LYMI | Lygodium microphyllum (Cav.) R. Br. | small-leaf climbing fern | Lygodiaceae
|
| LYPA3 | Lygodium palmatum (Bernh.) Sw. | American climbing fern | Lygodiaceae
|
| LYGOD2 | Lygodium Sw. | climbing fern | Lygodiaceae
|
| LYFE | Lyonia ferruginea (Walt.) Nutt. | rusty staggerbush | Ericaceae
|
| LYFR3 | Lyonia fruticosa (Michx.) G.S. Torr. | coastalplain staggerbush | Ericaceae
|
| LYLIC | Lyonia ligustrina (L.) DC. var. capreifolia (P.W. Wats.) DC. | Lyonia ligustrina var. foliosiflora | Ericaceae
|
| LYLIF | Lyonia ligustrina (L.) DC. var. foliosiflora (Michx.) Fern. | maleberry | Ericaceae
|
| LYLIL | Lyonia ligustrina (L.) DC. var. ligustrina | maleberry | Ericaceae
|
| LYLIS | Lyonia ligustrina (L.) DC. var. salicifolia (P.W. Wats.) DC. | Lyonia ligustrina var. foliosiflora | Ericaceae
|
| LYLI | Lyonia ligustrina (L.) DC. | maleberry | Ericaceae
|
| LYLU3 | Lyonia lucida (Lam.) K. Koch | fetterbush lyonia | Ericaceae
|
| LYMA2 | Lyonia mariana (L.) D. Don | piedmont staggerbush | Ericaceae
|
| LYPA4 | Lyonia palustris (Pursh) Small | Cynanchum angustifolium | Asclepiadaceae
|
| LYRUR | Lyonia rubiginosa (Pers.) G. Don var. rubiginosa | St. Thomas staggerbush | Ericaceae
|
| LYRUS | Lyonia rubiginosa (Pers.) G. Don var. stahlii (Urban) Judd | Stahl's staggerbush | Ericaceae
|
| LYRU2 | Lyonia rubiginosa (Pers.) G. Don | St. Thomas staggerbush | Ericaceae
|
| LYTRP | Lyonia truncata Urban var. proctorii Judd | Proctor's staggerbush | Ericaceae
|
| LYTR3 | Lyonia truncata Urban | Dominican staggerbush | Ericaceae
|
| LYONI | Lyonia Nutt. | staggerbush | Ericaceae
|
| LYFLA | Lyonothamnus floribundus Gray ssp. aspleniifolius (Greene) Raven | Catalina ironwood | Rosaceae
|
| LYFLF | Lyonothamnus floribundus Gray ssp. floribundus | Catalina ironwood | Rosaceae
|
| LYFLA3 | Lyonothamnus floribundus Gray var. aspleniifolius (Greene) Brandeg. | Lyonothamnus floribundus ssp. aspleniifolius | Rosaceae
|
| LYFL2 | Lyonothamnus floribundus Gray | Catalina ironwood | Rosaceae
|