Wonder if anyone recognizes this approximately 1.5cm { 9/16"} translucent green caterpillar. They have nearly completely defoliated, to the midrib, a 1m x 1m plant. It now resembles R. stenopetalum. Haven't noticed any damage on nearby plants, other than a little damage to young growth on a R. 'Fin's Yellow' {maybe a R. luteum hybrid} and a Fernleaf Beech, which seemed to have no caterpillars on them. It seems to have legs along the entire body length. Have checked BugGuide and searched here, but haven't found anything yet.
Could it be a winter moth larvae? Have a look at this photo: http://exoticpests.gc.ca/photo.asp?...perophtera brumata&auteur=(L.)&lang=en&pest=i Winter moth is listed as a pest that likes Rhododendrons. Here is the link to the full article: http://ravageursexotiques.gc.ca/ins_details_eng.asp?pestType=ins&lang=en&geID=1000088 Here is some info from the Integrated Pest Management Manual for Landscape Pests in British Columbia: http://www.env.gov.bc.ca/epd/ipmp/publications/manuals/landscape_pests/chapter9.htm Cindy
Cindy, thank you very much for the informative links. I don't think it's the Winter Moth, Operophtera brumata or O. bruceata though, as it doesn't seem to be a looper, arching it's back as it walks, and no white stripe noticeable. Trying www.whatsthatbug.com and haven't noticed anything resembling it either. Maybe it will change into something more easily recognizable. Another pic showing the legs, about 6 pairs behind the 2-3 larger front pairs, and guess that dark area was its lunch. Haven't seen a defoliated Rhododendron like this before, hoping it survives. Starting to wonder now if maybe the deer got most of the leaves , but then what very few were left had a lot of these caterpillars on them and there seems to be caterpillar droppings from top to bottom of the plant.
I think these caterpillars are not butterflies larvae, but sawflies larvae (which are close relatives of wasps). True caterpillars never have more than 6 pairs of legs.
Thanks very much BJellyfish, that helps to narrow it down a lot. I wasn't certain of the number of legs till the last photo was blown up and assumed it was a caterpillar. Thinking it is likely an Azalea sawfly larvae. Either Amauronematus azaleae or Nematus lipvskyi, it seems to match their descriptions, www.extension.umn.edu/yardandgarden/YGLNews/YGLNews-June0106.html#azalea
