I read the whole article and I can't find the part that backs up your statement. Not saying it might not be there, but telling people to figure it out on their own isn't super helpful.
In fact most of the article seems to agree that planting trees is a net good for removing CO2 and that the biggest problem is finding enough room to plant all the trees that are needed.
In fact most of the article seems to agree that planting trees is a net good for removing CO2 and that the biggest problem is finding enough room to plant all the trees that are needed.