|WikiProject Lepidoptera||(Rated Start-class, Low-importance)|
For what it's worth: I have seen these on my land in Great Falls, Montana for the last several years. Two of these caterpillars are in my kitchen where I have some spurge in a vase. I am observing them short term. Their appetite is voracious. The land they came from has a myriad of native grasses, clovers and many types of weeds. The ONLY plant I have seen them on and eating is the Spurge. Big Sky Pyro (talk) 23:22, 8 August 2009 (UTC)
Edibility of Spurge Hawk Larvae
With reference to Spurge Hawkmoths, the article says:
"the white and red spots appear as the caterpillar increases in size, and in a few weeks it becomes a most beautiful object, and so conspicuous as to attract the sea-gulls and terns, which devour them in numbers"
I find it most unlikely that the caterpillars are devoured by birds. Spurge plants have a toxic sap, and it is far more likely that the Hawkmoth larvae are brightly coloured in order to advertise that they too are poisonous (having redeployed the toxins from consumed Spurge leaves). I have actually watched a Spurge Hawkmoth larva drink the white, toxic sap oozing from a broken Spurge stem. —Preceding unsigned comment added by 126.96.36.199 (talk) 12:45, 5 July 2010 (UTC)