Equisetum x moorei Moore's Horsetail RR DD N
This hybrid between E. ramosissimum (Branched horsetail) and E. hyemale (Rough Horsetail) consists of single stems with no branches and every one we saw was topped with a cone although the spores are thought to be sterile. Some of the stems had long black collars (LHS) at the internodes but most had small ones (Middle photo). As we hoped, there was a fair amount of old growth as this hybrid is semi-evergreen. The black collars have weathered to light grey in the old growth in the right hand photo.
One of the parents of E. x moorei (E. ramosissimum) is only found in four places at most in England and is very rare. This hybrid occurs only along one short stretch of coast near Arklow in the Irish Republic and not at all in England, Scotland or Wales. However like many of our rarities it is not difficult to find once you are in the right place as there are many hundreds of stems growing by the road.
Roadside near Arklow, Republic of Ireland 22nd June 2007
Added on 25th June 2007, updated 2nd January 2009, updated 29th March 2010