Explore 23,508 Species
Field Elm
Ulmus minor Mill.
Ulmus minor Mill. (field elm) is a small European elm, susceptible to Dutch elm …
Chinese elm
Ulmus parvifolia Jacq.
Ulmus parvifolia Jacq., also called lacebark or Chinese elm, is a hardy ornament…
Siberian elm
Ulmus pumila L.
Ulmus pumila L. (Siberian elm) is a small deciduous tree native to Asia, with a …
slippery elm
Ulmus rubra Muhl.
Ulmus rubra is a medium-sized North American deciduous elm with edible bark used…
rock elm
Ulmus thomasii Sarg.
Ulmus thomasii, or rock/cork elm, is a slow-growing North American elm once valu…
crisped pincushion
Ulota crispa (Hedw.) Brid.
Ulota crispa, the crisped pincushion moss, is an acrocarpous moss native to east…
Gutweed
Ulva intestinalis L.
Ulva intestinalis L. is a widespread green alga with tubular branched fronds and…
Broadleaf Sea Lettuce
Ulva lactuca L.
Ulva lactuca L., common sea lettuce, is a widespread green alga with food and bi…
California bay
Umbellularia californica (Hook. & Arn.) Nutt.
Umbellularia californica, or California bay laurel, is an evergreen laurel famil…
Narrow Navelwort
Umbilicus horizontalis (Guss.) DC.
Umbilicus horizontalis, the horizontal navelwort, is a succulent perennial flowe…
Lamb's-tail
Umbilicus oppositifolius Ledeb.
Umbilicus oppositifolius (syn. Chiastophyllum oppositifolium) is a hardy Caucasi…
Wall Pennywort
Umbilicus rupestris (Salisb.) Dandy
Umbilicus rupestris, or wall pennywort, is a European succulent plant with histo…
Mexican buckeye
Ungnadia speciosa Endl.
Ungnadia speciosa Endl. is a small multi-trunked deciduous shrub or tree with pi…
sea oats
Uniola paniculata L.
Uniola paniculata (sea oats) is a C4 dune grass used for sand stabilization alon…
Caesar weed
Urena lobata L.
Urena lobata L. is a hairy plant with palmately lobed leaves, pink-violet flower…
Scratchbush
Urera baccifera (L.) Gaudich.
Urera baccifera, the scratchbush, is a nettle-family flowering shrub or small tr…
Para Grass
Urochloa mutica (Forssk.) T.Q.Nguyen
Urochloa mutica, para grass, is a perennial grass cultivated as livestock forage…
smooth golden fleece
Urospermum dalechampii (L.) Scop. ex F.W.Schmidt
Urospermum dalechampii is a hairy Mediterranean herb with yellow flower heads th…
False Hawkbit
Urospermum picroides (L.) Scop. ex F.W.Schmidt
Prickly goldenfleece (Urospermum picroides) is an annual weedy flowering plant i…
Star of the Veldt
Ursinia anthemoides (L.) Poir.
Ursinia anthemoides (solar fire) is an annual flowering daisy-like plant native …
Little Paraseed
Ursinia nana DC.
Ursinia nana DC. is an ornamental annual daisy native to disjunct regions of Afr…
siberian hemp-nettle
Urtica cannabina L.
Urtica cannabina (hemp nettle) is a perennial flowering herb in Urticaceae, nati…
heartleaf nettle
Urtica chamaedryoides Pursh
Heartleaf nettle (Urtica chamaedryoides) is a stinging flowering nettle native t…
great stinging nettle
Urtica dioica L.
Urtica dioica, or stinging nettle, is a stinging perennial herb with a wide dist…
