It’s late September and your last chance to sort out any ragwort problems, says Herefordshire company Micron Sprayers, which offers a weed wiper for dealing with this highly poisonous plant.

Attempts to scythe down ragwort may temporarily hide the problem but will only make matters worse in the long run, says the company. That’s because this normally biennial plant will switch to a perennial lifestyle rather than dying after seed-set.

Ragwort survives even a severe winter, thanks to its food-rich tap roots, and resumes growth in spring to then flower the following summer. What’s more, seeds already on scythed-down ragwort stems will mature and add to the ragwort seed bank in the soil.

A group of pyrrolizidine alkaloids are responsible for ragwort poisoning in livestock, although it’s their breakdown products called pyrroles that actually cause the damage. Once eaten, pyrrolizidine alkaloids are absorbed by the gastro-intestinal tract and then strike at the heart of the animal’s metabolism by destroying liver enzymes. Horses and other equines are especially susceptible to ragwort poisoning.

The only way to control ragwort is the use of a recommended herbicide, but spraying tall stems without contaminating agriculturally useful plants (pasture grasses and clovers) and ecologically significant species lower in the sward is practically impossible, says the company.

Micron’s WeedSwiper is a vehicle-mounted applicator which exploits height differences in the sward, directly applying herbicide to tall ragwort stems without contaminating other plants by drips or drift.

It works off a 12v power supply and can be tractor mounted or towed behind an ATV, pickup or tractor.

All units can be folded and operated at narrower widths than their designated maximum working width by utilising the simple boom end break-back return system. For example the three-metre unit allows application in one, two or three-metre widths.

Sensors in the 150mm contact pads allow automatic control of the fluid flow. Their height can be adjusted to suit the terrain and height of the ragwort above valued plants in the sward below. All units are supplied with pad covers to prevent accidental contamination and to safeguard operator safety.

Versions in 2m, 3m and 6m widths are available and all can be used at narrower widths by folding the boom. A mounted 2m non-fold unit costs £2795 and an optional trailer is £750.