Houstonians may be feeling blue about a new ranking of the greenest cities in the U.S. Among the country’s 100 largest cities based on population, Houston ranks 99th across 28 key indicators of “green” living in a new study from personal finance website WalletHub. The only city with a lower ranking is Glendale, Arizona. Last year, Houston landed at No. 98 on the WalletHub list. “‘Green’ living means a choice to engage in cleaner, more sustainable habits in order to preserve the pl...