Naked Science Forum
Life Sciences => Plant Sciences, Zoology & Evolution => Topic started by: AllenG on 24/02/2010 01:28:25

In front of my house is a 250 year old oak tree.
It can cover the ground six inches deep in the autumn.
While sweeping leaves off of my front porch I started to wonder how many leaves could possibly be on this tree.
I know it will vary by species, but does anyone know how many leaves are on a mature tree of any kind?

I did a little searching and found a one line answer (don't know if it's true) that a mature oak has in the neighborhood of 250,000 leaves.
Which BTW (I was watching a show on population tonight) means that if every leaf in a forest represented a person and at 250,000 leaves per tree and 40 trees per acre (recommended density for an oak grove), that forest would be 800 acres in size.

I have not run into studies of numbers of leaves, but rather the surface area of all of the leaves. Estimates of surface area have been done by waiting for the leaves to fall and then using what looks like a hat pin and pushing it through the leaves on the ground. The number of leaves pierced is counted at each sampling site. The sampling sites are spread out on something like 1m intervals like a grid. You cover the entire area where leaves fell. Then the number of leaves pierced is the number of square meters of leaf surface if a 1m grid is used. Multiply this value by 2 if the surface area of interest includes both sides of the leaf.