Equisetum diffusum D. Don, Prodr. Fl. Nepal. 19 1825. (Syn: Equisetum arvense subsp. diffusum (D.Don) Fraser-Jenk.; Equisetum diffusum var. caespitosum MildeEquisetum diffusum var. nudum MildeEquisetum diffusum var. paucidentatum C.N.PageEquisetum diffusum var. polystachyum MildeEquisetum diffusum var. ramosum Milde ;Equisetum mekongense C.N.PageEquisetum wallichianum C.N.Page );
Pakistan to China and Indo-China: Assam, Bangladesh, China North-Central, China South-Central, China Southeast, East Himalaya, India, Laos, Myanmar, Nepal, Pakistan, Thailand, Tibet, Vietnam, West Himalaya as POWO;

The Himalayan horsetail (Equisetum diffusum) is a perennial that averages at 10-25 inches. The Himalayas plant is silica rich and has a rhizomatous stem. This shiny brown stem can have many small hair-like roots and may also grow tubers.
(From Wikipedia on 14.2.15)


ANJAN55 Please identify this Equisetum sp. : 4 posts by 2 authors. Attachments (6)

Can this pteridophyte be identified from photos alone?
Date: 31st October 2014
Place: Dehra Dun
Habitat: Riverside (Tons river)

Yes it can indeed. Equisetum diffusum.

NSD-5 March 2017: EPHEDRA for ID : 4 posts by 2 authors.
seen this Ephedra plant during my recent Himalaya visit near Chamoli Uttarakhand.
Pl ID 

Thanks, … Pl. try to check with comparative images in efi site.

This plant may be Equisetum diffusum

Equisetum arvense L. ???? : 6 posts by 2 authors. Attachments (4)
Location: Soureni, Mirik, India
Date: 18 May 2017
Altitude: 4500 ft. 

No, arvense does occur in the high Himalaya behind the main ranges, and in the far west, but not at Mirik.  The common Himalayan species is this, E. diffusum, closely related to arvense and I treat it as a subspecies.

Copy pasting from Flora of China
Equisetum arvense Linnaeus :
Forests, forest margins, under bushes, meadows, banks of rivers and streams, open fields; sea level to 3700 m.
Equisetum diffusum D. Don :
Under bushes, roadsides; sea level to 3400 m.

Not sure what information of relevance to these taxa in India your post from FoC provides, but I’m afraid I can’t recommend following the Flora of China (actually the “Flora of Errors”) for many things, though it’s OK concerning Chinese distribution for these two. But as you may know from Indian literature, the distribution, altitude and ecology of E. arvense subsp. arvense and subsp. diffusum in the Indo-Himalaya is very well known, along with where they occur in terms of depth into the Himalaya – and has been well known for many decades.  As you can see, the altitudes given for the whole of China (including boreal China) are complete nonsense as far as the situation in India is concerned!  Subsp. arvense is confined to high, semi-dry inner Himalayan areas and becomes progressively rarer eastwards – finally dying out eastwards in Nepal. It is not known in West Bengal, or Sikkim, nor Bhutan or Arunachal Pradesh.  Subsp. diffusum on the other hand – the common N. Indian taxon – is in the outer Himalaya to C. Himalayan ranges and goes right through N.E. India.  In India, one is a typical European element dying out to the east and quite typically only reaching as far east as E. Nepal (at high altitude behind the Himalaya), the other is a Sino-Himalayan element, extending as far west as Pakistan. They are easy to distinguish as arvense has single ridges in the sheaths and diffusum has double ones, also arvense is sterile-fertile dimorphic with brown, achlorophyllous fertile stems that do not develop green branches, but die off while diffusum is fertile on persistent and green branches and is not sterile-fertile dimorphic.
     You will find details in much Indian literature, including my paper on pteridophytes of the far-west Himalaya (in Fern Gaz. 2010), also in the Ferns and Fern-Allies of Nepal 1: 86-89 (2015) and of course in the Annotated Checklist of Indian Pteridophytes vol. 1: 61-62 (2016), which is where you need to look concerning details of Indian pteridophyte species.

Thank you … for elaborated enlightenment !

SK1491 07 Oct 2018 : 3 posts by 2 authors. Attachments (7)- around 500 kb each. 
Location: Phedi, Nagarkot
Date: 21 August 2018
Elevation:5500 ft.
Habit : Wild 
Which Equisetum is this ??

E. diffusum (i.e. E. arvense subsp. diffusum), though the photos don’t actually show the double ridges.  As you will have read, only two species occur in this region of Nepal, and they are very distinct.
Do feel free to contact the National Herbarium in the usual way – Dr. Dhan Raj Kandel will immediately identify all these well known species for you – it is what the National Herbarium is for.  I think you would find it very worthwhile to visit and consult the herbarium!


Equisetum arvense subsp. diffusum (D.Don) Fraser-Jenk. ?? : 7 posts by 3 authors. Attachments (10)- around 400 kb each.
Location: Okharpauwa, Nuwakot, Nepal
Altitude:  5500 ft.
Date: 13 September 2018.   
Habit : Wild

To me also appear close as per images at Equisetum diffusum

It’s E. diffusion not E. arvense.
The cone of arvense is different

Nepali Name : आँखे झार Aankhe Jhaar

Equisetum diffusum D.Don : 9 posts by 3 authors. Attachments (3)- 1, 2 & 3 mb.
Location: Tarakeswar, Okharpauwa, Kathmandu
Date: 17 October 2019
Elevation: 1471 m.
Habit : Wild

Attachments (2) – 1 & 6 mb. 

is there a water stream near by?

Wall is wet and water seeping around!

Photos do not show a close-up of the ridges on the main stem-sheathes, so although it is E. diffusum (E. arvense subsp. diffusum), we can’t learn much of its diagnostic stem character.


Equisetum arvense Linnaeus: 7 very high res. images.

Location: Sundarijal, Kathmandu
Altitude: 2055 m.
Date: 09 December 2021
Habit : Wild

To me it appears closer to images at Equisetum diffusum compared to those at Equisetum arvense, and with whatever little I could comprehend from keys at Flora of China and illustrations- onetwo and three.



Help me to identify Equisetum sp. from kashmir: 3 high res. images.

It is a difficult sp. and images are not sufficient. Guess Equisetum palustre L. !

One more image

Please check !

These are Equisetum diffusum. A. Soni sent me the first two (without collector) and I told him they are inadequate as we must see a close-up of the stem-sheath and teeth, to see if the ridges below the teeth are double or single, and I had to see a little of the stem below the strobilus to see if it was green and branched – all characters of E. diffusum as opposed to E. arvense.
So your  last photo, which I hadn’t seen before, shows (just!) that it is diffusum with double ridges.
Glad you showed the tip of the come as that shows it is not E. ramosissimum which, despite its great variation in branching forms, always has a pointed little mucro at the top of the cone.
P.S. in J. & K., E. arvense is generally commoner, and higher and further into the valley etc., but you get E. diffusum more commonly in the outer hills and foothills, where was it from in J. & K. (and A.K.).?

The specimen was collected from ganderbal district of Kashmir India

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

To me appears close to images of Equisetum diffusum at:
https://efloraofindia.com/2015/02/14/equisetum-diffusum/ (similar to other observations there)

I feel it appears close to images at Equisetum arvense L.

Well it’s only close to E. arvense in that this species is related to E. arvense. But this is the well known E. diffusum, distinguished from E. arvense by having monophyadic stems, i.e. fertile stems are green (with chlorophyll) and develop branches. E. arvense has two types of stem (diphyadic), the early season fertile ones, being brown, without chlorophyll or branches and with short stems and wide, loose sheaths on them. After that the completely sterile green trophic stems appear and have whorls of branches.
I think E. arvense is a development from E. diffusum in adaptation to cold northern climates (it also occurs up very high in the West Himalaya). E. diffusum occurs throughout the temperate Himalaya at medium altitudes.
I have actually treated E. arvense as a subspecies of E. arvense, and prefer to keep them at subspecific rank.


Equisetum diffusum D.Don: 7 very high res. images.

Location: Godam, Chandragiri, Kathmandu, Nepal
Altitude : 1612m.
Date: 31 October 2023
Habit : Wild


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