Seen as a pest by many, most people don't realize these turn into beneficial moth pollinators.
I've never had any tomato plant killed by these caterpillars, most quickly recovered and grew new leaves infact. Unless your plants are for work or you live off the grid and your life depends on tomato's, you don't have to worry if you see these caterpillars. I even plant extra tomato's solely to put extra hornworms on to ensure more moths.
Wasps naturally target some of them, so chances are half won't survive for long, but some will always make it to pupate. Kill all the caterpillars and you hurt the beneficial wasp population as well, nature has no trouble balancing itself out we don't need to intervene.
Tomato hornworms have a black 'horn', Tobacco hornworms red with black tip 'horn'. Both eat nightshade plants including wild nightshade which is an invasive weed.
If left alone they turn into these beautiful; beneficial moths, which deep throated flowers need to pollinate them no other animal can reach deep enough to get nectar.
