Sticky Rain? Sap or Insects?

Are you noticing sticky or gummy little drops all over your car when you park under or near a tree? That stuff is honeydew, which is basically aphid pee. Aphids are little sap sucking insects. They're constantly dropping little drops of honeydew (their excretion) as they feed.

Recently, aphids seem to have really exploded, and you can see their drops all over cars around town. At this point in the season, your trees will not be harmed by aphids. They are basically just an annoyance. You have a few options:

1. Ignore them
2. Spray the trees with water from the hose
3. Spray the trees with insecticidal soap

I would not go as far as using other pesticides, because this is only a temporary problem. With the cold snap, they may die off on their own. If not, give it a few weeks or less. They will probably go away.

In the meantime, don't park under trees!