SK1311 22 JUL 2018 : 3 correct images.
Location : Chandragiri Hills, Kathmandu, Nepal
Elevation : 4400 ft.
Date : 28 June 2018
Habit : Wild
Which Equisetum sp.?
Are you sure second and third pics belong to Equisetum? To me looks like any flowering/fruiting bunch..
It was in the same area and thought to be from same plant. May be different. My carelessness.
I suggest to examine the ridges on the sheaths (single or double) and look it up in Khullar’s book or any other descriptive literature. Ferns of Nepal 1 (free from Godavary) even illustrated its close relative from up in N.W. Nepal. I expect you will presumably have read that fertile material is yet more distinctive, but you photographed young, sterile shoots.
Equisetum species so far in efi site with images