On Sat, 07 Nov 2009 02:06:18 -0600, sherwin dubren
wrote:

FarmI wrote:

Why do you make a distinction between leaf mold and compost? Aren't
they the same thing?

No, they aren't the same thing even though compost may have some leaves
included in it.

Leaf mould is made by piling leaves and then letting the pile rot down for a
couple of years without disturbance.

My leaf piles in compost bins take only one year to process. I do not
add any enhancers to them, except for water. It is key to keep these
leaf piles damp, as I can see dry portions never cooking. It is also
important that they are chopped up. Otherwise, they mat together and
this also prevents decomposition.

Leaves have lignin in them

My checking on the web says that stems and wood contain more lignin
than leaves, so I don't think this is the reason for them taking so
long to break down.

and thus
they take a long time to rot and, unlike compost, it is a cold rotting
process rather than a hot one.

Now, my compost piles have some grass clippings in them, so this may
account for the fact that they get nice and hot, even steamy on colder
days. However, I have seen recommendations of 2 parts of grass to
every part of leaves for a pile. In my case, I think the grass is
than 10 percent of the total, but everything cooks just fine in one
year.

Leaves decompose by using fungal
decompostition IIRC whereas compost is made by bacterial decomposition
(again, IIRC).

Leaf mould is valuble as the end result of decayed material is more durable
in the soil than 'normal' compost (because of the lignin).

From what I read, lignum is present in all vascular plants, and occurs
in higher amounts in wood than in leaves.

Another difference is that Leaf mould is made of just leaves and compost is
made of a combination of materials and includes a high nitrogen content
which is not present in leaf mould.

Except for processing time, I don't think the nitrogen affects the
plants covered in leaf compost. There are more natural ways the soil
to fixate itself with nitrogen. My experience is that leaves will
break down in a years time, assuming the pile is kept consistently
damp and the leaves are chopped up.

Sherwin

Some leaves take forever to turn into leaf mould, for example, Plane tree
leaves.

Nonsense. In fact planetreee (sycamore) foliage being thinner with
lacier finer vein structure than most decomposes more readily than
most leaves, much of the spaces between the veins dry and blow away
before the leaves fall... my sycamore leaves (actually London
Planetree) except for the stems are fully decayed within four weeks of
falling while maple leaves can lay about all winter, oak leaves
typically hang on all winter and fall when new growth begins in
spring, and are still recognizable 2-3 years after falling.... conifer
leaves can still be viable ten years later. A pretty good indicator
for which types of leaves decay more readily is to observe which are
more attractive to Japanese beetles and other leaf munching insects...
the more easily digestible the more quickly they will decompose.
Japanese beetles love sycamore, linden, pear, apple, etc., sycamore
about the top of their list, except maybe rose leaves. I've never
seen Japanese beetles attack oaks, maples, beech, birch... the more
resin/tannin the less attractive to munching insects and the more
resistant to decay. Planetree leaves are not at all resinous, in fact
rabbits and deer love them.

You guys are masturbating each other with semantics. The only
distinction between "compost" and "leaf mold" (leaf mold IS compost)
is that with leaf mold the organic matter is composed mainly of
leaves[period] Only total morons (completely uneducated) would argue
a difference between bacteria/fungi and organisms (bacteria/fungi ARE
organisms) in relation to digesting organic matter, they're one and
the same.... doesn't much matter whether organic matter is digested
by mycelium, passing through a beetle, a worm, or a cow.

Of course after all is said "compost" is not a gardener's ultimate
goal, composting is what a gardener does to produce fully decayed
organic matter: humus.

Merriam Webster

: 1com·post

noun
Etymology: Anglo-French, from Medieval Latin compostum, from Latin,
neuter of compositus, compostus, past participle of componere
Date: 1587
1 : a mixture that consists largely of decayed organic matter and is
used for fertilizing and conditioning land
2 : mixture, compound
---

: leaf mold
noun
Date: 1842
1 : a compost or layer composed chiefly of decayed leaves
2 : a mold or mildew that affects foliage
---

: my·ce·li·um

noun
Etymology: New Latin, from myc- + Greek helos nail, wart, callus
Date: 1836
: the mass of interwoven filamentous hyphae that forms especially the vegetative portion of the thallus of a fungus and is often submerged in another body (as of soil or organic matter or the tissues of a host); also : a similar mass of filaments formed by some bacteria (as streptomyces)