Ulex and Vernonia are both what?
Ulex Ulex (commonly known as gorse, furze or whin) is a genus of flowering plants in the family Fabaceae. The genus comprises about 20 species of thorny evergreen shrubs in the subfamily Faboideae of the pea family Fabaceae. The species are native to parts of western Europe and northwest Africa, with the majority of species in Iberia.
Grex (horticulture) The term grex (pl. greges or grexes; abbreviation gx), derived from the Latin noun "grex, gregis" meaning 'flock', has been coined to expand botanical nomenclature to describe hybrids of orchids, based solely on their parentage. Grex names are one of the three categories of plant names governed by the International Code of Nomenclature for Cultivated Plants; within a grex the "cultivar group" category can be used to refer to plants by their shared characteristics (rather than by their parentage), and individual orchid plants can be selected (and propagated) and named as cultivars.