Were there any half-chewed leaves? Sometimes the damage pattern is a good clue as to what's chewing.

If I saw a completely stripped milkweed, I would think to myself, "last instar cat."

Jeff

and, duh, why am I posting to this forum if I don't want those cats to eat my milkweed.

it's all for them in the end, i just don't know where they skedaddled to.

Monarch cats do not cut off milkweed leaves, they begin chewing them, and generally move onto a fresh leaf without having finished the one they started. I would expect to see half-eaten leaves if monarch cats were around. There are two different milkweed beetles that eat the leaves, and both of these are messy eaters, in the sense that half-eaten or damaged leaves will be present when they are done. I am not sure what critter is responsible for what you are seeing. I hope you are able to keep observing, so the mystery is eventually solved.

ericwi, I think we were interpreting the original post in a different way.

I was reading the phrase "chopped away and eaten" to mean that the whole leaf was gone, down to the stem. This kind of stripping is what large cats (Monarch and Milkweed Tussock Moth) do to my plants.

I think perhaps you might have been reading it as, "the leaves were cut off at the stem and lying on the ground"? Or something similar?

Jeff

hello everyone:

by "chopped away and eaten" I mean what Jeff said, which is that the leaves are completely gone and all that are left are drying out and dying milkweed stems.

if it helped the cats, they are fufilling their mission.

A rabbit (or two) has been squeezing into my garden and eating the common violets, the rice button asters, and some of the leaves on my cantaloupe vines - there's almost nothing left of what they eat, just the main stem.
Deer may also eat milkweed, I don't know - if it's swamp milkweed, it would have less of the poisonous stuff in it than common milkweed, but wasps will kill and eat monarch cats that are eating Mexican/tropical MW (very milky), so the milk may not be as poisonous as we thought.
Sherry

Although I have never personally seen a milkweed stalk totally stripped of leaves by monarch caterpillars, it does seem possible. I have spoken to the monarch cats who are currently residing in our yard, about their eating habits, and they have agreed to "try harder" to finish each leaf before moving on to the next. No guarantees, though...

Hee-hee. *bows*

By the end of the season last year, what with 50 Monarch cats and about the same number of uninvited Milkweed Tussock Moth cats, I had many a plant with no leaves left.

Jeff

I've got some smaller plants that were stripped of leaves too - mostly the A. incarnata, but also my one A. variegata plant. I'm pretty sure that it was slugs that ate most of the plant. We had weeks of rain and the slugs are out of control.

Most of the Asclepias has also been attacked by wilt or fungus too (like the bigger A incarnata and the A. syriaca). I lost a few branches of the A. tuberosa, but that is faring better overall.

It's been a terrible year for my milkweed. But haven't seen a single Monarch yet, and hoping there will be enough to raise a few when they show up.

We have no monarch butterflies this year in PA please feed them and send them north.

Hebdemnobad
if you have Monarch cats your lucky, havent seen any here.

How about squirrels using the leaves for nesting? I've had a couple make nests here, they don't seem too particular about what they use. Any new squirrel nests nearby?

it has struck again, around 100' from the scene of the first incidents:

here are some pics:

http://www.ifam.net/garden/eaten_milkweed_wide.jpg
http://www.ifam.net/garden/eaten_milkweed_closer.jpg
http://www.ifam.net/garden/eaten_milkweed_side.jpg

fwiw these are the first plants i've managed to transplant without the growth immediately dying.

Hebdemnobad - I am seeing the same things - smaller plants bitten down to the stem. What could it be?

After closer examination, I found two young cats. That brings me up to 25 since the 4th of July.

hebdemnobad,

What kind of milkweed is that in your photos? I have never seen such large leaves! Do you have any seeds of that milkweed to share or trade? I would love to have that large of a leaf type milkweed!

Mechelle

I have similar occurences on my A. syriaca. I have no answer to what could be doing this. It's not caterpillars. I haven't had any eggs on my common milkweed.
I do have plenty of ants though, and not alot of aphid action, so I'm really stumped as to why the influx of ants (large ants, that is). I don't have deer. I have plenty of rabbits and woodchucks, but neither have ever touched any of my milkweeds, plus, the damage is too high up. Doubtful that it's squirrels either.
And Mechelle; I hate this milkweed. It's tall, ugly, and I have never had a butterfly lay eggs on it. Plus, it spreads like mad, and mine has never even gone to seed. I normally cut the pods off, although I did leave 2 this year. Why, I'm still stumped...

I frequently have deer come in the spring and eat my A. syriaca. They sometimes strip off the leaves or sometimes even eat part of the stalk. If there are clear cut lines, it's probably deer.

I get eggs on my syriaca. But do you have other milkweeds in the area? I've found that the monarchs seem to prefer species with more tender foliage, so I used to get them on my incarnata but since I lost that, I only get them on my syriaca.

Mine are bit off mid stem, not the leaf the whole stalk, clean like cut with a knife, no leftovers on the ground. Got new plant it is on a plant stand with foil around it about 1 ft up. all was good for 2 days, this morning the tallest spike was nipped even with foil.