I live outside Houston, Texas. As you have probably heard, we are going through a very bad drought. We're about 30 inches behind on rainfall this year. We have lost 5 large Silver Maple trees. We don't want to put in any more maples because of the tremendous surface root system. What kind of trees would do well in our area and mot have surface roots. Also we would like them to not be so expensive as to empty our bank account, which when your on Social Security there's not a lot there anyway. We look forward to your suggestions.