If you are looking for a medium-size tree that not only has eye-catching blossoms, but it tough and adaptable as well, you might want to consider the choice of the Society of Municipal Arborists as its 2011 Urban Tree of the Year. The attributes that make golden raintree (Koelreuteria paniculata) a good choice to withstand the rigors of street-side planting also make it an attractive, low maintenance addition to many home landscapes.
Unlike many flowering trees that bloom in spring, midsummer is when the golden raintree displays its bright yellow flowers in large (18 inch), drooping, conical panicles. The large, bi-pinnately compound leaves let light filter through, making it easier to grow grass or gardens under this tree's canopy than that of trees with a denser crown, and they change to golden-yellow in the fall. Additional seasonal interest is provided by the large, yellow-green, lantern-shaped fruit capsules in autumn.
Hardy in zones 4-8, it most commonly matures to about 20-25 feet tall (although it is known to grow as tall as 30 to 40 feet). It is tolerant of heat, drought, urban pollution, and wind; has few pest or disease problems; is adaptable to many soils; and usually requires little pruning. Its main drawback is the litter created when the fruit capsules drop and a tendency to self-sow, so it may not be the best choice near a patio or walkway.
For more about golden raintree, go to: Society of Municipal Arborists.