normally, there is not issue with a large tree out in the middle of an open lawn becoming too large so we don't care how big it gets. But as it grows taller, we usually want the bottom of its canopy to act like a ceiling, providing shade and the sense of shelter. However, if that "ceiling" is too low, it becomes not an advantage, but a disadvantage. Does a person look better with a lot of hair covering their face. Usually not. The same is true for a house. When viewed from the street, if lower tree branches cover too much of the view of the house, it doesn't look good. Also, one must always be cognizant of the ultimate size of the tree. When it's 100 feet tall, would one want branches that are 6' off the ground? Another common problem with branches that are too low is that as they grow, they hang further down and become obstructive to actually using or maintaining the yard. Also, too many branches that are too low produce oppressive, gloomy shade... especially when trees are grouped together. Yet another factor is that high ceilings not only feel better in houses, but also outdoors. A low hanging canopy just does not feel as good as a raised one. I don't have enough space or time to convince anyone here in a short message, but start observing and you'll see it's true. I notice that almost everyone prunes trees in REACTION to how they are right now. Never in ANTICIPATION of what they'll be in 3 months or later. It is this reactionary pruning that is a bigger job and costs more. A limb that's 10" in diameter was at one time only 1" in diameter. At 1", it could be safely and easily removed by anyone. At 10" in diameter, it could only be removed by a professional. Just to make the same single cut (to remove the branch) requires about 75 or 80 times the amount of actual cutting work as when the branch was only 1". The limb structure on trees "opens" as it grows because branches grow longer, heavier and they end up hanging down. The same thing will happen with your tree. The branches that begin at 5' ht. on the trunk and now aim up, will eventually hang down. And they will be a whole lot fatter and heavier by then. When that time comes you'll surely want them removed because then they will be obliterating the view of your house, obstructing the use of your yard and producing oppressive shade where grass (or barely anything) could grow. But then the cost of removing them then will be exponentially higher. Today, you could do it yourself with a home depot pole pruner. In ten years, It will cost several hundred dollars for a professional to do it. Then, the cuts that need to heal over will be massive and maybe even look disfiguring. Today, they would be small and heal quickly. Removing branches a little early (in anticipation of what's to come) might at first make it seem like too much trunk is showing relative to the canopy. But in a rapidly short time, as pruning will do, it just causes the tree to grow faster in all the areas that remain... which is mainly the top of the tree. So very quickly, things look back in perfect order again.

Paulownia trees are the fastest growing trees on the face of the Earth. They create great shade, and when it gets cooler, the leaves can bend inward to bring in light just when you need it most, cutting home energy costs. The trees can grow up to 18' a year, but usually grow, I will say, 8 to 13' a year. But, Paulownia can be invasive, only if you have more than one tree that is not a clone. If you are willing to keep up with the little extra work, I say go for it! The fastest growing species of Paulownia, I heard, is Paulownia Elongata. But, there is supposed to be not an extremely too much of a difference of growth rates between Paulownia species. Also, have you heard of Gumbo Limbo? It is a tree, native to Florida, that you can literally stick a 3 foot long branch in the ground to create a whole new tree! Gumbo Limbo has a fast growth rate. Look it up on Wikipedia. I also heard you can grow any type of Willow tree very easily from cutting, too. Weeping willow is the fastest growing of all the willows. But, there are some bamboo alternatives for shade, that can grow about the same about as a Paulownia. Bamboos rarely ever flower, and, if you get the right clumping variety, they will not be invasive.

There really is no grass ( turf) that does well under oaks. Oak trees don't much like grass under them either. From the link St Augustine For Florida Lawns "'Palmetto' 'Palmetto' was a selection found by a Florida sod grower in 1988 and was released in the mid 1990s by Sod Solutions. It is of intermediate growth, with shorter leaf blades and internodes than many other cultivars, but is slightly larger than the dwarf St. Augustinegrass cultivars such as 'Seville' and 'Delmar'. It has a nice growth habit and does well in full sun or partial shade, but not in dense shade. It is sometimes referred to as drought-tolerant, but research has not shown that it has any greater degree of drought tolerance than other St. Augustinegrasses. It often has problems with disease, particularly in Florida's humid environment. It tends to have a lighter green color than many other cultivars." The link below has good info too. Here is a link that might be useful: Growing Turfgrass in the Shade

Docmom, I have sent you some messages via Houzz messaging system. I assume you have not received them? I am going to try again. If you don’t get anything, please see if you have emails enabled. Thanks! To see your messages while on Houzz (rather than / or in addition to email) go to the upper right corner. Click on "your Houzz". In the drop down menu, click "your Ideabooks". On a header on that page, you will see "Messages". Click on that and you will see any messages in your Inbox. There's a menu at left for Sent messages and Received messages. It took me a while to find this! ;)