Tulip poplar is not a tree I would worry about in terms of honeydew production. Many of our landscape trees are susceptible to aphids or other honeydew producing species (e.g. scale insects). It is almost impossible to find a tree that will not be infested with some kind of honeydew producing insect for at least some of its life. These infestations tend to come and go naturally and they don't last for more than a year or two. They also tend to be more severe and frequent on trees that are stressed in other ways. Keeping your tree happy by ensuring that it has everything it needs in terms of nutrition and proper irrigation, will help it stay pest free.