Equisetum Sp. ID

[GerryNick2]

Not being a plant expert I am struggling to identify this Equisetum Sp., I think it is E.arvense as opposed to E.telmateia, confirmation would be appreciated.
Growing on wasteland which is prone to flooding.

Gerry

[Lancashire Lad]

Hi Gerry,

I think this is without doubt E.telmateia.

The plants show numerous sheath teeth, far in excess of the 6-12 that E.arvense would have.

(E.telmateia has between 20-30 sheath teeth ringing at the stem at each of the nodes).

Also the stem of E. telmateia is approx 10-15mm diam. whereas E. arvense is only 3-6mm diam. The stem of your plants definitely look to be thicker than 3-6mm.

Finally, E.telmateia can reach a height in excess of 40cm, whereas E.arvense only reaches about 25cm. Again, the plant in the first photo looks to be more than 25cm.

Regards
Mike.

[GerryNick2]

Thanks very much Mike, based on the dimensions you kindly provided there is certainly no doubt in my mind that this is the Great horsetail - E.telmateia.

Gerry