Ha Giang Prov., Bac Me Distr., Phieng Luong municipality, around Phieng Day village.
Degraded primary broad-leaved humid evergreen forest along rocky canyon of small stream at the base of mountains composed with solid crystalline highly eroded limestone at elevation 900-1000 m a.s.l. around point 22°38′43.8″N 105°19′19.8″E.
Terrestrial herb 1.5-2 m tall on secondary grassland on alluvial slope of limestone mountain. Flowers yellow. Commonest weed.