Following the course of the discussion what you would do next is show a closer view of the flowers - except it has occurred to me that this would be a Melaleuca. Although of foreign origin these much-planted trees are prevalent in warmer parts of the US, to the point of weediness in some areas.
It is an acacia, as the smell of the roots will confirm. It is known here in New Zealand as Acacia 'Rewa' and grows to be a dense shrub or sometimes a small tree. At times it has been listed as either a cultivar of Acacia verticillata or Acacia riceana but it doesn't really match either species. I've only ever known it to be propagated vegetatively, indeed I don't recall seeing seedpods on it, so my guess is that is a old hybrid, the origins of which have long been lost. Tony Rodd may see this and provide clarification.
Clicking to enlarge twice I see the individual flowers are a little different than I thought previously.
