Trees in forest

How many trees do you have to have to consider it a forest?

Well, quite.

How many hairs constitute a beard and would it really not be a beard if there were just one less?

a “forest” used to refer to an area of land set aside by a sovereign as his official hunting ground. Its size was determined by ownership and suitability. Kind of like a private game preserve.

Forest aren’t so much defined by the number of trees as how densely packed they are.

“Forest”, as generally used, refers to a type of ecosystem dominated by trees and other woody vegetation. According to the U.S. National Vegetation Classification system, within a forest the trees must have overlapping crowns, with at least 60% cover. Areas with from 25% to 60% cover are considered “woodlands”, rather than forests. From 5% to 25% is called a savanna.

There is no such thing as a forest. We can prove this inductively. Let P(n) be the statement: “A group of n trees is not a forest.”

We need to show:[list=1][li] P(0) P(n) -> P(n+1)[/list=1]Now, 1 states if you have no trees, you don’t have a forest. There is no forrest without trees. 2 says that if a group of n trees isn’t a forest, then adding one more tree will not make it a forest. If you don’t have a forest, adding one tree will not make a forest.[/li]
Therefore, there is no n such that n trees make up a forest.

Cool, Darwin!

I have a mixed forest just outside of my window. An oak, Two Virginia Pines, and a Hickory tree! After that, it’s allparking lot, until you get to the forest across the street, which is five trees.



  1. A dense growth of trees, plants, and underbrush covering a large area.
  2. Something that resembles a large, dense growth of trees, as in density, quantity, or profusion: a forest of skyscrapers.


  1. Having relatively high density.
  2. Crowded closely together; compact: a dense population.
  3. Hard to penetrate; thick: a dense jungle.


  1. Of greater than average size, extent, quantity, or amount; big.
  2. Of greater than average scope, breadth, or capacity; comprehensive.

I hope this “reselmbles” an answer

Obviously, DrMatrix can’t see the forest for the trees.

Forty-two. The answer to life, the universe, and everything.

DrMatrix, you prove there is no forest with an integer number of trees. Give me an axe and I’ll prove the existance of half-trees. Well?

But wait, how do you count trees, anyway? Does a seedling count? Does a seed count? When it’s still hanging on the parent tree? Still growing? While it’s falling off? Not until you’re sure a squirrel won’t eat it? Would 1000 squirrel droppings add up to one tree? What about splitting a tree into a number of shoots, scions, or whatnot? Would grafting create one from two, and what about the remaining parts? The cloned cell clumps used in modern agriculture, each cell being able to grow a ‘separate’ plant?

No, the only reasonable answer is, since there’s nothing you can do to a tree that really increases the number of it/them, and there had to be a time when there was a single first tree (ignoring creationism and multievolution) - there’s still only one tree. And I wouldn’t be surprised if this one isn’t merely the product of a deranged imagination.

What’s the difference between a forest and ‘the woods’, then?

Run Forest…


If a forest is a larger than average amount of trees with a density higher than the surrounding area, does that mean that one tree counts as a forest in the desert where there are no trees?

What if it’s a banyan tree? It certainly LOOKS like a forest.

What about the monster aspen grove that covers 200 acres from a single root system?

OK. You got me. My proof only applies to an integral number of trees. I also didn’t consider trees with square or cube roots, because that would be irrational.

But what if you have your own forest of bonsai trees, each in a square planter?

Are those bonsai trees irrational because they have square roots? :smiley:

So it’s like I suspected, trees are imaginary. You know, I googled for square radishes, beets, and turnips, but all I found was the usual cube melons. Not roots. :frowning:

And this, a page with a picture of a tree with a pythagoras-tree root system:

How do you define this:

Is this a small forest of six trees? Or not a forest of one tree?