The spruce and other local conifers (I live by the Bohemian Forest/Bayerischer Wald) have pollen that seems to be low allergenic by design. I know a lot of people who are allergic to birch or weed pollen, but not to spruce.

Pollen allergies have definitely skyrocketed in Sweden. We used to be able to sit in an office and work all year without hearing people sniffle and sneeze.

Now it's like an epidemic, at least half the office is affected.

I moved to Germany as an adult from a completely separate biome, and I’ve got terrible problems with allergies I never had in my home country

Spruce is also a problem in Poland, especially southern. Leaf trees have been replaced with "fast growing" spruce over a hundred years ago.

Germany has half the percentage of forest as Japan

"why do you sneeze, we don't do that Germany"

Hayfever allergy rates are growing around the whole world, Germany included.

It’s known that repeated exposure to allergens can cause allergic symptoms in people previously without them. For example https://en.wikipedia.org/wiki/Bird_fancier%27s_lung https://en.wikipedia.org/wiki/Farmer%27s_lung

I actually seemed to grow out of hay fever when I was in my early 20s. Perhaps coincidentally this is also around the time I developed an allergy to cannabis from overuse. Wonder if they’re related somehow.

As someone who has suffered from hay fever for my entire life, and also lived in many different locations, almost every move came with a 2-3 year reprieve from my symptoms while my body "discovered" the fun new local allergens.

Lots of people I know who moved here as adults have developed pollen allergies over the years. Some after a 2 or 3 years, some after 10.

I got hayfever on my 3rd year of living here, and it seems like quite a common pattern among immigrants I've noticed. I have hayfever back in the UK too, but I guess I didn't have a Cedar allergy - so it took time to develop.

I'd been wondering why my allergies go nuts every time I visit Japan, but never really suffered in other Asian countries. Cool to know now.

Upside is I discovered the trick of just taking fexofenadine every single day which had the side effect of solving my chronic sinus infections.

I would assume it has more to do with less exposition to hay/pollen in urban areas, for instance in years in Beijing I've had hardly allergies since it is not exactly green, though I went to parks, but here in Prague right now with everything blooming it's nuts.

Actually now that I think about it never head really problems with allergies even in Southeast Asia, though I was in very green areas, maybe humidity helps as well?

[delayed]

It can go the other direction, too: exposure to moldy home environments gave me (now resolved) food sensitivities, dust allergies, pet-associated allergies, etc.

You can definitely undertrain, or overwhelm, the immune system if not cautious!

Maine is 89.46% [0].

[0] https://en.wikipedia.org/wiki/Forest_cover_by_state_and_terr...

Still behind Finland (73.7%) and Sweden (68.7%) though and Laos (71.6%) as well.

https://en.wikipedia.org/wiki/List_of_countries_by_forest_ar...

75% of it is mountains, and not exactly inhabited.

Not really for a mountain island. Being near the coast means increased moisture and wind, which hits mountains to make rain. Take a japanese-sized slice off the coast of most countries and you will find lots of forrest. Think the pacific northwest, or the bits of hawaii not covered in lava. Then compare parts of the australian coast with no mountains.

This might have something to do with it:

> When the sugi and hinoki forests were first planted in the 1950s and 60s, they weren't meant to stand forever. At the time, it was assumed they would be gradually cut down and replanted over time, as had been the case before the war. But as Japan's economy boomed in the late 60s and 70s, major cities like Kobe and Tokyo grew rapidly, and it ended up being cheaper to import wood from other countries such as Malaysia and Indonesia.