It’s early morning and it’s cool enough for me to be wearing a good five layers of clothing but not so cold that my car windscreen needs scraping.  So it’s a little odd that I’m lugging a litre bottle of antifreeze around with me.  Stranger still that I’m nowhere near a car- any cars in fact, as I’m walking in a pretty determined fashion through Wisley garden and towards the Plants for Bugs plots.

No need to worry though. I am here for a very good reason.  Today, we’re setting pitfall traps – one of four methods used to regularly sample invertebrates on Plants for Bugs; the RHS research project designed to test whether invertebrate wildlife is at all bothered about the geographic origin of our garden plants.

Pitfall traps are composed of plastic drinking cups sunk into the ground and half-filled with diluted ethylene glycol (antifreeze). Traps are left in the ground for two weeks so that we can monitor the activity of all sorts of ground-dwelling invertebrates from ground beetles and woodlice to mites and springtails.

A freshly set pitfall trap, secured in the ground with a tent peg

In the past two years of recording, over 16,000 specimens have been collected from our pitfall traps and more than 250 species have been identified.  Now that the first traps of 2012 are in, we’ll have to wait a whole two weeks before we get any idea of what has been collected!

After two weeks in the ground, the contents of each pitfall trap are collected and returned to the lab for identification.  Photos courtesy of Helen Bostock (RHS)