Biology of Nettles

There are numerous nettle species world-wide, many of which are trees or shrubs. Within Europe only two occur as weeds:

Small Nettle
Urtica urens
– annual

Stinging nettle
Urtica dioica
a perennial and the most prevalent species in established pasture

  • Propagates mainly from extensive, creeping, rooting stolons
  • New plants are able to develop from root sections, so that chopping them does no more than multiply the problem
  • The more often the shoots above ground are cut, the more vigorous is the new growth
  • They will grow upto a height of 1 metre, eventually forming dense beds, which spread out across the field
  • Flowering period is from June to October
  • Germination occurs from the soil surface, even at low temperatures, when the grass sward becomes open or if the soil is disturbed

Impact on the sward:

  • Grass yield / grazing is lost mainly by competition from nettles for nutrients, light and moisture, but also from stock refusing to graze close to nettles

The quality of the conserved grass (hay, silage) is affected if nettles are present, as the stock will reject it