To revert to your original post, if you want another spring-flowering, small tree of a different color - redbud, crabapple (some are white flowered), Flowering cherry, etc. - would be a good substitute. Fringe tree is another one, but IS white flowering, and is late to leaf out. Hawthorns (some are native and some European or hybrids) do have white flowers for the most part - some have red - but the red fruits are interesting, and some have good fall foliage - being members of the rose family, they can get common rose family diseases, including fire blight, and they do have thorns. If you want a summer flowering tree, then there are possibly one of the hardier crape myrtles, stewartias (possibly not hardy), franklinias, and a few others - some of which will also have white flowers. You might also be able to grow and limb up a Peegee hydrangea, although the weight of the blooms will bow down the branches to a degree. If you can find one, a sourwood is summer-flowering, whitish and come in July-Oct., with good fall foliage. Virginia Witch hazel flowers in the fall, with yellow flowers - there are hybrids with European varieties, which might be hardy for you, in orange to red colors, that flower in early spring. Fall foliage is yellow.

This is my fault as I should have the read my response before I posted it. But the libray was closing and I was running out of time. Whenever, I plant anything. I put a mixture of topsoil, compost and the original soil that I dug out. That way I don't get the bathrub effect which would kill most of my garden, the other trees I planted which bloom just fine and my all roses. Other thing, is I also use earthright once or twice a year. I haven't yet this year but I have to this month or I have to wait until fall. Like I said I did talk to Johnson county garden extension office that told me that it might be growing issue. As the tree has really taken off in the last two year. The other times it didn't bloom were to late freeze but this year that shouldn't been an issue. In early May the lowest we got was 38 which did affect some of the leaves but not enough to keep it from blooming. There are some blooming in a near by city. Ants are not an issue because they prefer my Pin oak.

Syringa reticulata and Syringa pekinensis have both been available in the United States since the late 1800s. I have personally managed individuals from the turn of the century (early 1900s). These plants can be grown as multi-stemmed or single-stemmed small trees. That is a choice made by nurserymen growing the plant originally, and afterward by the party responsible for the landscape in which the tree is planted. There are a number of narrow selections of Syringa reticulata - 'Ivory Silk' is a popular and very common one. 'Ivory Tower' is another. These will have smoother gray bark. Syringa pekinensis is more variable in bark and form. A selection named 'China Snow' has fabulously exfoliating/peeling bark, competing with some of the ornamental cherries. It doesn't seem to have as heavy a flower display as many of the Japanese Tree Lilac clones. Bernheim has a collection of old specimens dating to the 1960s here in KY. These are durable plants, and ought to be used more widely.

Try Brady Nursery at 11200 West Kellogg, they advertise having the Japanese tree lilac on their website, so I would guess they would have it. Good luck!