July 17th, 2007
significant discovery?
A couple of days ago, I mentioned that I’d be posting about something that has occupied a bit of my time for the past week. This was the “suspense” that I talked about. Those of you who know your invasive species and are familiar with the dastardly Glossy Buckthorn bush (Rhamnus frangula), will understand the significance of this week’s discovery.
While out wandering along the paths here at the farm, I was stopped in my tracks by the sight of the above caterpillar tents or webbing — in a Glossy Buckthorn bush! The caterpillars had practically defoliated the whole bush. I shot a few close-up photos of them (see below). Buckthorn is a bit notorious for having few known pests to slow down its infestation of fields, fencerows and forests. While I have found the odd Cecropia moth caterpillar putting a large dent into the leaves of a Buckthorn now and then, these big larvae are just too rare to have any deleterious effect on the bushes. Now, a nice infestation of some species of tent-type caterpillars would be most welcome!
I put a few photos of the caterpillars up online, wrote a post about them and sent it to the local NatureList asking if anyone else has seen these tents on Buckthorn. There was no immediate response, but the list’s moderator, Dr. Fred Schueler, forwarded the email on to get another opinion. That response got me busy sending the email on to a couple of more people at Agriculture Canada. It turns out that these caterpillars are probably doing something that hasn’t been noted before — making a meal out of Buckthorn. The next move will be to try to ID these cats – although it’s been suggested that these are probably fall webworms. I’ve left most of the caterpillars in the bush, but brought one tent back to the house and have it in our screened porch, where I continue to feed the caaterpillars Buckthorn leaves. I can then watch them grow and photograph them at various stages. With any luck, at least some of them will pupate and become moths. I’ll try to get a positive ID on them as final instar caterpillars or as moths. With even more luck, perhaps the ones remaining in the bush, along with any moths that successfully pupate here at the house, will go forth and propagate even more caterpillars who like to dine on Buckthorn.
Okay, so this may not be the most earth-shaking news, but these caterpillars may turn out to be good news for those who are interested in the control of this nasty invasive species. I’ll post an update on their progress sometime soon.
Tags: Glossy Buckthorn, Rhamnus frangula, invasive species, caterpillars
July 17th, 2007 at 9:41 am
Excellent work!
Good science, and a good story. And supported with wonderful photography. The tent-and-orifice is an artistic creation of form and light in nature.
July 17th, 2007 at 9:52 am
Great sleuthing there, Bev, and very exciting news. It may not be great news for the Buckthorn, but it could be great news for those protecting the natural plant species in your area. I’m really looking forward to seeing what kind of moth emerges. You always have the best science projects going!
July 17th, 2007 at 9:44 pm
Bev, I just wanted to tell you how much i’m enjoying your pictures & website. I found it by accident when I was Googling photos of a caterpillar I found on my parsley plant (turned out to be a black swallowtail). Your photos are just stunning, thank you so much for sharing!
Best wishes from Oklahoma City,
Layla
July 18th, 2007 at 8:24 am
Robert – Thanks! The tent was quite spectacular when I first came upon it. I shot photos from several angles, but that “porthole” view was really quite neat.
–
robin – It really is quite exciting news to those who are interested in preserving native habitat. One local botanist who saw these photos was quite excited about the possibility of having some caterpillars that would put a dent in the Buckthorn. I do hope I’ll be able to raise a few moths off of these cats. I’ve had good luck with other species, but have never tried raising tent-type cats before, so it’s a new experience.
–
Layla – Thanks! I’m glad you found your way to my blog and have been enjoying looking around. It seems that a lot of people have mentioned finding Black Swallowtail caterpillars on their parsley or dill this year. It must be a great year for them!
July 18th, 2007 at 12:29 pm
I’ve never been so happy to see something defoliated. Ship some to Chicago!
July 19th, 2007 at 3:34 pm
Glossy buckthorn is pure evil. I have spent thousands of hours over the past couple of decades trying to control it. I love seeing those caterpillars munching away on it. It would be really coool if this turns out to be a previously undocumented host plant expansion for the species.
July 20th, 2007 at 9:24 am
Dave – Perhaps if these guys really get going, they’ll be spreading around the continent on their own wings! (-:
–
Doug – We’re overrun with it here at our farm. There’s really no hope of the two of us ever getting it under control, so we’ve just had to let it do its thing. It’s all over the place in this part of the country. I hope these little caterpillars will be able to successfully complete their life cycle, and that perhaps next year, we’ll see more of their tents and webbing. This afternoon, I”m taking some of the caterpillars to one of the local universities so that a researcher there can do a bit of experimenting with them as well. I have one tent doing quite well on the back sun porch, and the rest of the caterpillars are out in the tree.