Shore Horsetail

horsetail
Shore Horsetail (Equisetum x litorale)   Photo: Bob Ellis

A small colony of this hybrid Horsetail was found near a ditch in Carlton St Peter. The hollow stem and pattern of side branches alerted me to the possibility that this may be a hybrid. On closer examination under the microscope and comparing the cross section of the stem to one of its parents E. fluviatile, although the hole was around 80% of the diameter, the wall was thicker than E. fluviatile and had 14 clear ridges. On the other hand, the side branches which were cross-shaped in cross section showing more similarity to the other parent, E.arvense.

Janet Higgins
30.05.2020