When I first spotted Berberis sawfly larvae in my garden in October 2006, there was some controversy in the sawfly world about whether they represented a breeding population or not. Well, 22 months and several broods later, I think I can categorically state that we do have a breeding population here.
And though I’ve still not spotted the sawflies actually mating, this year, for the first time ever, I saw them laying their eggs on our Berberis bush. And you can see this too – by clicking here.
If you watch the video carefully, you’ll see why these insects are called ‘Sawflies’. They actually saw into the leaf, and deposit their eggs inside it!

So, the 2008 Berberis sawfly story began on 4 June, when I looked up from my desk and saw around 7 skittish Berberis sawflies flying around our Berberis bush. ‘Aha!’ I thought. ‘They’re back. And I recognise that behaviour. I think it means they’re going to lay their eggs…’
So, I watched. And I waited. And I videoed.

And this is what I saw …
Now, I have only recently got a video camera (thanks to the Merchant Adventurers’ Award I received earlier this year), so the film is not David Attenborough-esque in its quality. But I think it’s fascinating, nevertheless, to see the Sawfly actually sawing into the leaf …
When I was filming, I *thought* I was filming egg-laying, but I couldn’t be absolutely sure. And at first when I went to have a look at the leaf she’d been on, I couldn’t actually see any eggs. I had to look very very carefully.
Of course, once I had ientified the pockets of eggs, I was able to watch them develop day by day, until they actually hatched …

… and then began their familiar routine of gobbling up my Berberis bush, pooing profusely as they went! (As audiences at my National Insect Week, Ledbury Poetry Festival and Festival of the Rivers Buzzing! shows were able to see for themselves, as I took some larvae along to each of these shows.)

Find out more about Berberis sawflies (including photos and videos of eggs, larvae and adults) here
Hi,
Today, 24th June 2009, I have just noticed the entire defoliation of my berberis. My queery is will the berberis survive this attack. I have some larvae and one adult captured plus photos.
Hi Caroline
I’ve just checked with Andrew Halstead of the Royal Horticultural Society, and he says that your defoliated berberis ‘will survive and it will produce a new flush of leaves. These may in turn be eaten by larvae of the next generation. Repeated defoliations will weaken the plant and may result in stems dying back.’
Don’t forget to record your sighting with the RHS – at http://www.rhs.org.uk/surveys/submitrecord.asp?type=1
Hope that’s of help to you.
Best
Anneliese