Tuesday, 22 January 2019

A Week of Weeds - Hairy Bittercress

Hairy Bitter-cress: Cardamine hirsuta

Look at this fighter flowering already in January.  It's secret weapon is the speed of reproduction and explosive seed dispersal.  Brush against the plant when the seedhead is ripe and you set off a shower of projectiles, each one an irretrievable seed (on account of it's small size). Ballochory is the term for this - my new word of the day  (and not to be confused with barochory which is seed dispersal by gravity alone).  Hairy Bitter-cress  appears first as a rosette before sending up a number of stems which rapidly produce unprepossessing flowers.  Once primed the seed head reacts to your weeding efforts as a stimulus to explode.  "You are too late"  it says as it peppers your face with pellets. Moral - weed early, preferably at the rosette stage.


2 comments:

  1. These are one of out most prolific weeds. Apparently it’s edible and provides a hot cress like taste. I haven’t tried it!

    ReplyDelete
  2. Land Cress or American Cress is a cultivated giant variety of the same family. (This was the one that the children in the school garden dared each other to eat because of the peppery aftertaste.)

    ReplyDelete