Mulch can be defined as anything that facilitates the mycorrhizae.
Mycorrhiza - singular Mycorrhizae - Plural.
Mycorrhizae is a composite structure or organ, that is made up of tree root
tissues as well as fungus tissues. Mycorrhizae facilitate the absorption of
water with essential elements dissolved in it.
What I prefer top use as mulch is composted tree trimming that have gone
through a chipper. Composted at least a year. NOT FRESH CHIPS. Fresh
chips are chips that have living parenchyma cells and their contents
(protoplasm) smeared all over the place attracting undesirables. Composted
wood chips and leaves.
The wood has many benefits while they break down with the help of the
succession of microorganisms.

Mulch should be applied at 3 - 4 inches thick. Keeping it away from the
trunk flair (many people who have not dissected trees calls the flair at the
base of a tree a root flair. The flair is made up of trunk tissues and not
root tissues) at least 6". Mulch should be flat. If you edge the tree, do
not pile the edgings back up on the mulched area. Remove it. The more soil
you place on top of mulched area, the more you reduce the oxygen content
below. Trees do breath and they do require oxygen in a process called
respiration. That is the process where glucose is burned in the Krebs
cycle. So you can suffocate a tree in this sense.
Mulch is a maintenance process.

Mulching - http://home.ccil.org/~treeman/sub3.html and
http://www.treedictionary.com/DICT2003/M/index.html

Sincerely,
John A. Keslick, Jr.
Arborist
http://home.ccil.org/~treeman
and www.treedictionary.com
Beware of so-called tree experts who do not understand tree biology.
Storms, fires, floods, earthquakes, and volcanic eruptions keep reminding us
that we are not the boss.


"Dave" wrote in message
news
Bit confused on the mulching business as it has multiple meanings. The
mulch I've seen around some smaller trees was obviously put there to keep
the rif-raff out of the area. Not to promote growth of the tree. If
"mulch" could do both, great.
Dave

Keeping away undesirable organisms. Make sure the wood chips and leaves
have composted for at least a year.