Welcome!

I would like to point out that this is a myth: The neighbor said they need heavy pruning to flower

Crape myrtles flower just fine on their own in their native environment without being pruned. However, some people like to force a large amount of new growth to get MORE flowers. As you drive around (especially in winter), notice the artistically minimal pruning job that professional landscapers do in commercial plantings. This type of pruning highlights the graceful limb structure. Compare this to the butchering that some home owners do to their crape myrtles, leaving their plants with knobby appendages.

So while you might feel the need to prune your crape myrtles, please take the time to look into the right way to do it. You may have less flowers, but you'll have beautiful plant that is attractive year round.

Here is a link that might be useful: Crape myrtle pruning article

They also come in numerous cultivars and habits/sizes. There are some teeny-tiny ones, there are some shrubby ones, there are some small treeish ones and there are some medium to large trees

And as usual I hate to be the devil's advocate here but Crepe myrtles are extremely overplanted and their invasive potential is just now starting to be realized unfortunately.

Post a picture of your "sap trees". we should find out what that is for you.

"why do we grow grass?" because it gives all the people something to do. You'll be driving down the road and see an 80yr old guy driving his tractor over his 3 acre lawn. It's hilarious.

But welcome to the area and hope "yinz" have fun gardening here!

Hey. Welcome. Part of my childhood was spent in Pittsburgh. I loved it, although I literally walked to school in snow to my knees - uphill both ways. Great place. I hope you enjoy your new home in GA.
I'll bet the grass you see dead in winter is Bermuda and the grass you see dead in the summer is fescue. Because of the drought, this year might be an exception.
Have fun gardening in GA. The season starts in February and runs through November. Sort of a gardening marathon. Winters are mild, so you don't have to worry much about heaving. You'll discover a lot of great nurseries and gardening resources here. One of the best is UGA. I start most of my plant searches by typing UGA in front of the info I'm looking for. I'll start you out with a link to their list of gold medal winners for Georgia.

Here is a link that might be useful: Gold Medal Winners

What color do your crepes flower?
I think mine is a species of some sort. It has a single trunk and does not have the peeling bark either. It's white and it came from a seedling volunteered by a friends' tree. I occassionally find seedlings, but I prune my crepe directly after flowering to get rid of seed heads.
Although I don't knuckle the tree, I do grow plants under it so I trim out all the smaller interior cross growth that I can reach, and keep all the new growth off of the stem. This creates a much neater habit, and more light gets under the canopy.

GGG

There are some crepe myrtles that will only get a certain height and are better suited to shrub form rather than tree form. If you want the taller tree form, you're probably better off getting them already grown at a nursery.

As far as magnolias go, unless you have a very large yard and want a monster tree...get a Little Gem. They 'only' get to 35 feet. Just remember that magnolias molt every spring so don't think they are dying.

Welcome to Atlanta, Kate. I just came back from visiting family in Chicago and even though it was nice I realize I have grown fond of the South and can even see myself retiring here!

You've got tons of great info on crepe myrtles here. Regarding the southern magnolias, plant one judiciously as it can be a pain in the behind. They drop leaves and cones constantly (not just spring although copious then) so you need to deal with this by planting them somewhere where it doesn't matter that there's a bunch of debris under the tree; for example, not right over a Driveway or Walk (I know whereof I speak!). And don't limb up the tree (another egregious issue the previous owners saddled me with). Low branches make it easier to hide the debris er...mulch and anyway, the line of the tree is infinitely more lovely with low sweeping limbs.

Take care, hope to meet you at a plant trade.

Rose

Welcome to the south, and happy gardening! Watch out for details of the fall and spring plant trades that take place somewhere around Atlanta.

Welcome to Georgia and all the pleasant surprises that await you here between now and next summer.

Nell

Welcome to Atlanta. What a nice post! Yes, plant your magnolia grandiflora - "Green Giant" if you have the space. I planted 2 of another variety about 10 years ago, and they are magnificent. There are also a number of dwarfs available.