The way trees sequester carbon is by manufacturing wood, leaves, bark, etc. They cannot magic carbon dioxide into something that is not solid material. Leaves fall off and decay: some of that turns into compostable material; some is consumed by animals/fungi/bacteria releasing methane and/or carbon dioxide.

So what you’re asking for (whether you realize it or not) is bigger trees. As far as girth is concerned you can achieve the same effect with smaller trees anyway. You can only pack so many big trees into a given area but you can pack more small trees into the same area.

The only way you’re going to gain is with taller trees, because you have more wood for the same area. Which means we should all plant sequoias in our gardens.

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