They consume pine needles and can rapidly strip a small tree. When alarmed they raise up as seen in this photo. My wife says their little red heads look like baseball caps. Kuwait Art 5th Photo Exhibition. 2nd place Best Insect Photography Competition - July/August
Here is a link to some of my newest favourites: www.flickr.com/photos/drphotomoto/sets/72157619134603911/...
Here is a different variety of sawfly larva taken last year: www.flickr.com/photos/drphotomoto/3038729871/
And here is another view of the same species of sawfly (seen above) which was taken last year: www.flickr.com/photos/drphotomoto/2825648819/