There are a few books that say it is, but I've never found any on it, just willows. Maybe the authors think since red-spotted purples use willows AND black cherry, viceroys will, too. In my experience it's not the case, though.

Sherry

I caught a female viceroy and put her in a cage with lack cherry and willow she laid 10 eggs altogether but 7 were on black cherry and 3 on willow

Offer both, and the cats will choose, and I'm thinking they'll gravitate towards the Willow. You may also end up c two populations of cats, one on BC, one on Willow.
Interesting to see how the adults turn out...

Cats never made herinaculims all hached today the seven on black cherry were RSP!!!! All eggs from a viceroy! I was so shocked! Has anyone had something like this happen

And you actually witnessed the viceroy laying the eggs?

The reason I'm asking is, I saw a viceroy laying eggs on my willow growing in the big container, a Webb's willow, which is a dwarf version of black willow. I brought in three hatchling cats to raise myself and left the others on the bush. The other day I noticed some butterfly had laid new eggs - I don't know if the viceroy came back and laid more eggs or if a red-spotted purple laid them. RSPs use willow fairly often, as a matter of fact, I saw one laying an egg on a leaf on one of the willows that grows in the thicket where I go to get food for the three I'm raising myself.

If you're sure these RSPs came from the viceroy, then it IS very interesting, but not totally unbelievable to me. The old butterfly books say that viceroys, red-spotted purples and white admirals are all just different forms of the same butterfly.

A few years ago I raised some hatchlings that I found on the Webb's willow, assuming they were all red-spotted purples. They turned out to be about half and half -

{{gwi:471734}}

Since I didn't see the eggs these came from being laid, I don't know if they had the same Mama or not.

Sherry

I caught the female and watched her lay eggs in my cage I set her up in. I am astonished but a guy that sells moth cocoons said when you hand pair you can create hybrids so I would think it happens in nature. I cross breed checkered and cabbage whites and the eggs were viable. The adults that came out the males were like cabbage male and females were like checkered white female. Where did you get your webbs black willow
Thanks:)

I got it from Woodlander's in Aiken, SC, a mail order nursery that specializes in native plants. I've gotten a lot of eggs/cats on it since I got it. I'm growing it in a large container - since it's not supposed to get big, I'm hoping it'll be able to thrive there for years to come. Hmmm......that reminds me, I probably should take some cuttings from it, just in case.

Sherry