Forest tent caterpillars in southern Minnesota — March to Duluth begins!
By Paul Lundgren on May 17, 2010 in Creepy Stuff, Outdoors
I came across several of these disgusting silken mats of forest tent caterpillars on Sunday in the Minnesota Valley State Recreation Area, about 160 miles south of Duluth. I’m sure there’s some larvae busting from egg masses somewhere in the northern part of the state, too, but I haven’t seen any yet.
I think next summer is when things should start to get really gross around here, with a peak in 2012 … although I haven’t heard any official predictions yet. Anyway, it probably wouldn’t hurt to get stocked up on tin foil and dish soap, or whatever is supposed to keep the ravenous little beasts from chewing your trees bald. Perhaps someone can fill us in on good dish soap substitutes that are better for the environment but still make the “army” retreat. (It’s smart the way they invade every 10 years … just long enough for us to forget all their weaknesses.)
I saw a few (hundred) caterpillars on the Lakewalk extension a month or so ago, some of them trailing down on threads. Don’t know if they were Army Worms or not.
Did they look anything like this?
Or this?
I saw these in Duluth on April 22. They look a little like forest tent caterpillars when you see them and can’t compare them with the real thing.
I went dumpster diving on the U of M campus this weekend, and the trees and sidewalks were crawling with tentworms. Glad I haven’t seen any of them around here (yet)…
Craaaaaaap. I hate those things. So glad I’m not in the landscaping biz anymore. I’d come home and find them crawling all over my crap. Nasty.
Gross. Nightmare fodder throughout my childhood. I had really wanted to do some serious camping/hiking this year, and this might be enough to keep me out of the woods, if it’s as bad as I remember.
This makes me want to cry.
Girlfromnorthcountry, this news should actually make you more eager to do that camping/hiking. The caterpillars aren’t bad yet. Get your adventures in now. Next year is likely to be a different story.
The forest tent caterpillar is mostly a nuisance. Already weakened vegetation may not survive the onslaught, but I’ll take these buggers over killer bees, venomous spiders or zombies any day.
Ya know Paul, that is actually what I was just thinking! Get out on the trails now before the worms and skeeters take over the forest completely. Just curious though, is there any resource that might help me avoid the potentially bad areas? Probably not much to do besides wait and see. Wikipedia advises placing a bucket 1/4 full of water near the afflicted trees; the worms will be attracted and drown. Obviously that wiki author has not seen a Minnesota army worm infestation.
Like I mentioned, I haven’t seen a single forest tent caterpillar in Duluth this year. I’m sure they’re out there, but we shouldn’t see them in significant numbers until next year. So there aren’t really any “bad areas” around here.
Once they arrive in full force, I think everywhere remotely close to a tree is a “bad area,” including parking lots, the siding on your house, your hair, etc.
It’s awesome when they get smeared across your windshield when you turn the wipers on.
I like that bucket of water idea. Wait for that sucker to fill up, then apply heat and — bingo! — instant soup. Probably quite nutritious.
I’m from southern Wisconsin, and saw them there in March. I don’t think they ever got as bad there as I’ve heard they get here. Gulp.
My father used to take a blowtorch to their tents. eeeek!!
Gross, Paul. It sounds like you’re almost looking forward to the disgusting things. There was a family up on North Shore Drive a few years ago who successfully warded them off by creating barriers around their property… wish I could find that article and what they used.
Don’t forget the possibilities of Armyworm wine.
I haven’t had the pleasure of experiencing these things yet. So clue me in, a simple bucket of water placed next to a tree attracts them??! Any tree? Confused and mystified…
Oh no! Not the death caterpillars again! A sure sign that I’ve lived here too long.
They taste pretty good with worcestshire sauce or with cole slaw. Had them while camping one time. Good for protein.
Oh no!!! You know, I can take the cold … I can take blizzards … I can take having to take a plane halfway across the country to see my family … I can take my daughter growing up, speaking like the characters in Fargo — but I hate army worms. That is the one thing about Minnesota I can’t take! I may have to find a way to spend all of next summer elsewhere.
My sister was visiting one spring and I wanted to show her Enger Tower, we both about threw up with the millions of them crawling up those steps, needless to say she never saw the view from the top. Have you ever listened in the woods when they are munching and it sounds like rain? It’s their poop hitting the leaves. Completely gross, but at least they do not bite like the &*^^ blackflies or carry disease like the ticks. Still, glad I don’t have any oak trees. One house I had they were twirling from the oak like ballerinas--you honestly could not be in the yard as the wind would blow them right into your hair out of nowhere. ICK.
Gander Mtn. sells great bug hats for cheap -- stock up now. I used mine at the cabin the last time they were so bad. Still had to be swept with a broom before coming inside but at least they weren’t in my hair!
Cutter makes a spray that you attach to your hose. Spray the trees, grass, etc. and it will kill them, the larvae and help create a barrier for the rest. I have 4 bottles in storage already.
Or…buy an ostrich as they are the only thing that will eat the nasty worms!
So I gather they only attack oak trees?
These nasty things head for the deciduous flora in our midst(hardwood, broad-leaf trees like oaks, maples, birches, aspen/popple, etc.), essentially any non evergreen or pine tree. So evergreen and pine areas will fare better overall. Not sure re: cedars tho… Also, when the ruffed grouse numbers go up -- like they have been of late, the tent caterpillar numbers go up as well.
@Woodtick…any clue as to why there is a correlation? Never heard that before.
@Terry G…they make the underside of your car stink and it’s possible to slide on the road during a large migration or crossing. Glenwood near the entrance to Hawk’s Ridge can be tricky if you time it right.
My mom leaves town or stays inside the house as they freak her out so badly. Oh the anticipation!
@Piglet -- I will look into this and get back to you. Heard the correlation from a bird hunter pal.
It seems they target apple and crab apple trees the worst. I remember the trunks being covered so badly, it looked like moving fur instead of bark. The trees would have no leaves or blossoms. Sad.
I am so not ready for them to come back yet.
This will have a huge impact on the birch stands that were blown down after last winter’s ice storm up the shore around Finland. There’s a pretty good percentage of blowdown vs. standing vegetation, so it might be that there won’t be as much to munch.
Wow! Good thing I’m moving to Oregon this fall. I saw a couple of Army Worms crawling up someone’s shirt in St. Paul yesterday. Seems like they’re back right on time
I was out biking on the Tri-County Corridor in rural Douglas County yesterday and I counted at least four or five clusters of tent caterpillars along the trail. The larvae was just starting to emerge, but it wasn’t swarming yet.
7 or 8 years ago, I was working on the railroad near Aurora/Hoyt Lakes. There were so many squished up army worms on the rails that the ore trains couldn’t get any traction. They can stop trains if they want to.
Maybe if I was more ‘experienced’ with these critters I’d know the answers to my questions (I did check the web too). But we ARE talking about tent caterpillars, right? Not army worms? Each eats different things and I doubt the army worms hang around in tents (barracks maybe?).
Forest Tent Caterpillar or Army Worm?
DNR forest tent caterpillar 2003 update
And better yet…
DNR forest tent caterpillar 2009 update
Thanks TimK -- great resources!
Last Army Worm intrusion in 2002: I was building the Yurt in July. It happened to also be a banner year for ticks, mosquitos, gnats, and flies in/around Isabella. Every step meant death for a thousand small lives.
I look forward to the carnage.
They go after the deciduous trees, yes, but once they’ve dilapidated those… they have no issue moving to evergreens. Bastards. They’ll cover the sides of your house with their insatiable need to crawl up something. They’ll crawl up your leg if you stand in place for more than 30 seconds. They’ll make you want to puke.
I seem to remember them PLOWING parts of Scenic 61 for Grandma’s one year, no?
I was guiding in the BWCA during the couple of invasive years and I’m not going to lie-- I have ended trips short. I fondly remember the sound of rain which was poop, as you mentioned Jude. A rainstorm of worm frass. Lovely. I have spent a month in the high arctic with the worst black flies you can imagine and I would deal with that over this nasty ass things anyday.
Oh, and let us not forget the “friendly flies” that will then follow.
Tim K: That article from the DNR says they are called army worms because of the way they forage for food. I always thought it was because they looked like an army in that drab army green color, marching, marching…
mk: I totally forgot about those b-52 lazy huge flies that cling to everything….double ICKY.
Thanks for the links, TimK!! I’m fascinated by the pattern of infestation on that map, on both pages. Why does the swarm begin at the tip of the lake and taper off further inland? I wonder if it’s the trees or the cooler temperatures? Good info, more research needed.
Apparently, it’s worse than I thought in the southern part of the state. According to the MPR story embedded below, forest tent caterpillars are seriously attacking trees in the Twin Cities.
I still haven’t seen any in Duluth, though.
Today’s vocabulary word: frass — powdery brown caterpillar excrement.
By the way, if I had just moved to Minnesota instead of having lived here my whole life and experienced three FTC invasions, I would swear the whole thing was an elaborately concocted piece of local lore invented to freak me out — with the DNR and media all in on the conspiracy.
Looks like the DNT is picking up on story ideas from PDD again.
Anyway, Sam Cook reports that the DNR isn’t expecting and infestation in Duluth this summer.
DNR: Army worms aren’t expected this year
The MPR story contains the only instance I have ever noted of a reporter using the word “ishy.” This is solid, accurate journalism when it comes to forest tent caterpillars.
One of my favorite words that comes up in stories about forest tent caterpillars is “denuded” — as in “Last year the bugs denuded 30,000 acres of trees south and west of Lake Mille Lacs.”
When trees have all their leaves eaten off it saddens me, but when I hear a word like “denuded” it makes the whole situation sound a little illicit and fun.
I, on the other hand, don’t like or understand the word “denuded.” Shouldn’t that mean putting the leaves back on?
It reminds me of “unthawed.”
In the outskirts of Perham, Minnesota between the two lakes, Big Pine and Little Pine, they are all over the place. We have all kinds of different trees in our yard, Oak, Basswood, Maple, and some fruit trees. They are all over the place, I have to check my husband every time he comes in to make sure there are none on him. My daughter went after them with Dawn dishsoap and water in a spray bottle. And those friendly flies are annoying too.
I just found a forest tent caterpillar in our woods up past Two Harbors. Just one was enough to make me go “ish.”