Tuesday 27 August 2013

Pincushion

There is a diminutive Gall Wasp active at this time of year, which chooses to lay its eggs in the unopened buds of Dog Roses (Rosa canina) around these parts.  This little wasp has the tongue-tying name of Diplolepis rosae, more commonly known as a Hymenopteran or Bedeguar Gall Wasp.  The females of this insect, lay up to 60 eggs in the rose plant's buds causing the rose to grow a distinctive gall around the developing young, manifesting itself as a 'mossy' growth known as a Robin's Pincushion.
The unfortunate Rose plant begins to form these Pincushions about 18 hours after the wasp has laid its eggs, which affect both the plant's protein synthesis and the RNA in the cells surrounding the eggs.  This has the effect of making the cells enlarge and produce these uncharacteristic growth forms.  It takes between 12 and 36 days for the 'Pincushion' to be obvious with the Gall Wasp larvae developing inside the structure, safe within numerous tiny chambers.
When the gall is mature, it starts to turn red as the larvae continue to grow.  These larvae overwinter, even pupating safe within the gall before emerging in the Spring as fully developed adult Gall Wasps and almost immediately defecates all of the waste or 'meconium' which it has stored as it has been developing inside the gall.
Lots more can be found on this particularly fascinating website, which I thank for this information... Hedgerowmobile.com

1 comment:

New Hampshire Gardener said...

That's interesting and I kind of like the unusual effect. As long as it isn't on my roses, anyhow.