Location of plant: West Bengal north of Kolkata, India. This plant seems to thrive all along the roadsides even when covered in road dust. Locals tell me it irritates the skin when touched and therefore cows and goats will not graze on it. Could it be some form of Euphoria? I D help please!
It makes me think of Calotropis, which does have a milky sap and does grow in India. Asclepiadaceae. Do you have photos of open flowers and fruits?
It doesn't help me much. The first photo has one flower that looks similar to ones here: https://www.plants.usda.gov/gallery/pubs/capr_002_php.jpg Here is another photo: https://toptropicals.com/pics/garden/m1/EG_05_2014/Calotropis_procera3087.jpg There are some buds in the last photo on this page: Calotropis procera - efloraofindia