I just noticed that during and after the helgen attack, none of the trees around helgen were destroyed or caught fire.

Please don't take this personally:

Nitpicking yes?

I am not taking it personally, just curious

Probably because only Helgen was affected, not the trees.

Alduin's aim is better than most (including mine)

One of those unexplainable things, I never noticed it myself. Ash and sparks could easily have traveled into the grass and trees and started a blaze but it just wasn't put in. In like manner you're in the far north with possible sub zero temperatures, especially in the mountains yet you never freeze to death unlike some of the corpses, skeletons you come across. Fortunately the Frostfall/Hypothermia mod on PC fixes this.

Unfortunately though it blocks me from completing the test to join the Stormcloaks since I have no idea how I'm going to swim through freezing water while battling the killing cold not to mention carrying enough firewood to dry off and warm up while iceberg hopping. It puts up a formidable climate 'wall' to the quest.

Alduin had a frost dragon on standby at Helgen.

Never really noticed it myself. I honestly have only entered Helgen once after the attack there, maybe ill head off there today and see what I find.
I wonder if anyone starts to live there afterwards, like bandits or something.

Things in this game just aren't flammable. That's why you can start a fire in a library but nothing burns down.

Guess I shoulda figured. I'm actually on my way there heading to Riften. Hopefully they have some good loot. Lol

I think Barbas may have been marking his territory around Helgen, and everybody knows daedric pee contains asbestus.

I'm pretty sure there's an option in Frostfall to make a 'snowberry extract' that allows a certain amount of time swimming in freezing water without ill effects.

Thanks, I'll have a look at it at some point. In the mean time I've decided to do Season Unending. Will just have to see the way the wind blows so to speak.

I'm going with this ^

Dragons love trees. Trees are friends.

Well, the Firestorm effect is 100 ft. It is well within reason that the effect was contained within the walls of Helgen. After the initial Firestorm, the rest was just targeted shouts. All well within the walls.

Skyrim has good emergency services. The Whiterun hold fire crew fought the fires bravely and efficiently while Whiterun hold police pursued the culprit.

Whenever I go to Helgen I imagine my character saying to the bandits "Wanna know why people left in the first place?" Then call Odahviing, run off and turn invisible, to watch the slaughter