an ancient weed

The horsetail leaves have started emerging in the back garden.  This is an ancient plant, and one of the most determined and ineradicable weeds found in the UK.  The spore bearing cones appeared several weeks ago, and are now withering, but the leaves will be with me until the autumn.  They are bright green, thin fronds carried on brittle central stalks.  Given moisture they reach 30-40cm in height, while in a dry year they are somewhat shorter.

Questions about horsetail, or Equisetum arvense, crop up regularly on Gardeners' Question Time, and are the cue for the panel to laugh and suggest moving house.  If Bob Flowerdew is on the programme that week he will say that horsetail can't stand mowing, and that the questioner can put their garden down to grass and grow standard trees.  This would be fine, assuming they wanted that sort of a garden.  The roots of horsetail are black, and brittle, and are said to go down so far underground that coal miners have found them growing in the mines.  They run, and horsetail will cover a large area, limited only by whether it finds conditions to its liking.  Black polythene is no cure.  The horsetail will sit underneath, biding its time until the ground is clear again, if necessary for years, and the fronds are capable of finding their way through woven landscape fabric.  It is a plant of poor drainage and compacted ground.  Here it runs around in the back garden, where the underlying clay comes close to the surface, and is absent from the front, where the sand goes on down seemingly for ever.  Just to be on the safe side we have a rule that no roots or waste containing soil from the back garden goes on the compost heaps at home.  Instead it all goes to the municipal dump, where it can be composted at higher temperatures than we can achieve.

Looking on the bright side, we don't have ground elder or Japanese knotweed, and horsetail, although visually intrusive, is not a very competitive plant.  When we first moved here I put a lot of effort into digging it up, or painting its shiny leaves with a mixture of glyphosate and wallpaper paste, before deciding that it was impossible to kill and instead I needed a strategy to live with it.  What I do now is pull up the leaves when they appear, as many as I can get to (which is dependent on weather and what else is going on at the time).  They will regrow but not as tall.  If I keep at them the regrowth ends up so short that it is hidden among the other plants.  This is one reason why I'm so keen on getting a continuous layer of low herbaceous planting between shrubs and the showier herbaceous feature plants.  The horsetail doesn't seem to affect the growth of the garden plants, and I avoid having to see too much of it.  At least, as it doesn't get going until late April and early May, the ground is left more or less clear for early displays of small bulbs and suchlike.  It withers in autumn, leaving remarkably fragile, insubstantial remains.

The leaves of horsetail naturally accumulate silicon, and in times gone by it was used for polishing pewter, according to Richard Mabey.  We do have a pair of pewter plates on the mantelpiece that are pretty black and in need of a good polish, so maybe I should try it sometime.  Unfortunately Mabey doesn't give any instructions about how to go about this domestic task, whether the horsetail should be wet or dry, and if I should use a bit of soap or anything with it.  Mabey also says that the leaves if boiled in water make an excellent fungicide against mildew.  My normal approach to mildew control is to try not to grow things that get mildew, but maybe I should try that too.  We'll see how it goes.