Lotus, Double Bird's Foot Trefoil 'Plenus'

Considered invasive by the MN DNR
From their website....
"Ecological Threat:
Birdsfoot trefoil forms dense mats chok...Read Moreing and shading out most other vegetation.
It grows best in the Midwest and is most problematic in prairies and disturbed open areas, such as roadsides.
Prescribed burns increase seed germination making it troublesome in native prairies.
This European species has been introduced to the U.S. and Canada for livestock forage and erosion control along roadsides. It is still sold commercially. "

Dark green, tiny leaves form a dense tight mat. Completely covered by orange buds which open to double yellow flowers. Evergreen in war...Read Moremer climates. Can withstand being walked on 3 or more times daily. Grows fast. Hardy to zone 5.