Trees

I went to the nursery yesterday and bought two trees, a zelkova and a pink crepe myrtle (approximately this color). One of our rather hideous hackberries bit the dust a year or two ago - the city took it down because it was dying - after dripping sticky and stinky "honeydew" from the hackberry aphid invasion all over the street and sidewalk. The websites I see claim that hackberries live 150 to 200 years, but most of the ones on our street seem to be near the end of their lives at around age 50-55 and I've seen several others around town around the same age coming down as well. UC-Davis seems to be claiming the aphids don't do any real damage to the trees, so I'm not sure what's causing the demise of our neighborhood hackberries.