So the sapling Populus tremuloides that I used to sleeve females over last year has almost no foliage on it this year, presumably because it is in a very shady spot. This means that I don't think sleeving the female Papilio canadensis butterflies over it is likely to result in egg laying. If I can find some nice saplings that I can transplant I might try that later, but in the meantime I have sleeved the females that I caught onto branches of trees out at another location. Here is what it looks like:
Unfortunately, with this set up I can't set up the heal lamp overhead which may have helped induce egg laying last year. This is why I tried to select spots where there is at least partial sun. The butterflies have to be hand fed if you keep them like this or else they will dehydrate, so far I have been feeding them a nectar solution once a day via a soaked cotton ball. The females may or may not have mated, and I didn't have success attempting to hand-pair females last year. Depending on how thins go I might try it again this year.