The caterpillars eat, mostly, the young, nutrient rich, growth of plants so it stands to reason that the frass they generate would be a fairly good fertilizer. Those caterpillars would use a fair amount of the Nitrogen to make the protein their bodies need to grow so a high amount of N probably would not be present although at the speed they do eat they may not be able to process all of what is available. I have found only references to this frass being a good fertilizer for the plants, nothing about the analysis for specific values.

Yes, I HATE them! They can decimate my trees in a day!!! I go on egg patrol all the time! Luckily the eggs are so big, I can find them quite easily. They love citrus and also sansho (Mountain ash, sichuan pepper)! Ashita

Put a paper towel or newspaper at the bottom of the container, you will need to clean out the container, probably every day. oh, here's one of the shots I was looking for: Hopefully they will attach to the sticks (can you see the wings? they are getting ready to eclose, probably the next morning) After they attach, I put them in a mesh laundry container, put the sticks in flower foam to hold them upright and cover the container with a light towel/cloth...and use clothes pins! I put them on the porch until they hatch. They need to be protected because of predators (ie wasps, etc). Mine nearly always eclose in the morning...like 8 or 9 a.m. They need time to flap their wings before they fly off.

I tried a trio of citrus at my last house here in Temple: 1 dwarf lemon, 1 dwarf lime, 1 dwarf orange. Didn't really care if they produced fruit, just wanted the flowers, scent and insect action on the blooms. They would come back beautifully each year off their roots, even after multiple freezes, they'd get about 4' tall by winter again. They'd die back kand the cycle would just repeat itself. I think you have to be way down in the Houston/Galveston area to have much success with citrus. There's a reason Florida dreads freezes each year on their orange crops. I gave up and finally just dug them up, as I kept getting stuck with their thorns and reaped no blooms or benefits. Now Duranta, I had great luck with. Had two huge ones flanking the entry of my driveway. Loved the blooms; loved the winter berries; loved how they could die off in winter to the ground and come back with a vengeance and look better and better each year. Didn't like how they killed out the St. Augustine underneath them, but they are pretty summer heat and winter freeze hardy in zone 8.