I am looking for the best air purifying trees for Zones 7a or 7b? All I can find online is about the best indoor air purifying plants. (Yes, I understand all trees will purify but I'm wondering if there is a list of the air purifying champs?)
These people definitely know the tree topic — and since they’re active both in Africa and in the UK, they likely would have knowledge for a zone with conditions like yours
BTW, I'm in zone 6, with the forest quite near, but still near our house we've planted some trees (such as a hard-maple cousin to sugar maple), a weeping willow, and some spruces that I'm glad we have for shade and for the influence on the air.
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