Significantly, this line marks the southern limit of the birch tree, a plant whose pollen is one of the causes of hay fever in northern Europe.

值得注意的是，这条线标志着桦树的南部界限，而桦树的花粉是引发北欧花粉热的一个原因。

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You can also control hay fever by showering when you come in from outside to remove pollen from your hair and skin.

当你从外面回到家中时也可以洗个澡来赶走你头发和皮肤上的花粉。

youdao

You can also control hay fever by showering when you come in from outside to remove pollen from your hair and skin。

当你从外面回到家中时也可以洗个澡来赶走你头发和皮肤上的花粉。

youdao