Although I understand your desire (I wouldn't mind being in a hammock right now!), I typically don't recommend planting fast-growing trees. Fast-growing species generally develop problems, because they have soft wood that breaks easily. These trees are much more likely to lose limbs or fall during storms or periods of heavy winds. Many fast-growing species are more likely to catch diseases, and die sooner too. About the time they become effective as a shade tree, they may suddenly die or decline. Then you have to start over again. I highly recommend planting varieties such as oaks (Quercus), which are much longer lived and will not develop as many problems. In many cases, trees with a moderate growth rate have gotten a bad rap as slow growers. If provided with the right growing conditions, they can add 1-2 feet or more of growth per year.