pine bark mulch

[Ja...@eznet.net]

I was wondering if Pine bark mulch is harmful to certain plants!!!!

[m&v]

In <35906CFE...@eznet.net> Ja...@eznet.net writes:
>
>I was wondering if Pine bark mulch is harmful to certain plants!!!!
>

No, but it decomposes very quickly and is not much less than a much
better shredded hardwood, or cedar mulch. If it is deco bark mulch, it
can matt down and cause plates to form which are impenetrable by water
or air...in the longrun, it is not a good mulch to use. I don't
recommend it. Shredded mulches are superior.

V

[Sad Plant]

Aged(composted) pine bark is excellent mulch, just a little bit harder
to come by. This is the compost of better commercial potting soils.

[Susan M. Sanders]

In article <6mqoq7$3...@dfw-ixnews5.ix.netcom.com> m&v,

My personal experience (of about 25 years) is just exactly the opposite.
In my garden, pine bark mulch lasts several-to-many years, shredded has
to be replenished after the first season. What's more, I nearly lost my
rhodendrons the year I had them mulched with shredded wood because their
roots were completely dried out, despite regular watering--the mulch had
formed an impenetrable barrier to any water getting to the roots. The
day one of my rhodendrons opened its buds, only to have the flowers
completely wilt and die before the end of the day, caused me to
investigate what was going on, and that's when I dug beneath the mulch
layer to discover that the soil underneath was completely dry. I've been
mulching with pine bark mulch ever since and have never had a similar
problem. Because of its chunkiness, there are always gaps between the
chunks that allow air and water to get beneath the mulch.

[Susan M. Sanders]

In article <6mpmgg$tua$6...@node2.nodak.edu> Robert J Goos,
go...@badlands.NoDak.edu writes:
>Organic fertilizers, such as some municipal composts, can be very saline.
>If too much is applied, there can be some salt damage.
>
>People around here think that our city's municipal compost is the same
>thing as potting soil...WRONG...it is a highly saline material that should
>be used sparingly...like a fertilizer.

Ann Arbor, where I live, does regular testing on its municipal compost to
check the levels of anything that's important for growing, both the good
and the bad, and copies of the results are made available to the public.
Ann Arbor compost, at least, does not have high salt levels. (On the Ann
Arbor garden walk two weeks ago, at least two of the gardens were owned
by people who boasted of using vast quantities of municipal compost, and
they had marvelous gardens). If other municipalities are not testing
their compost, local gardeners should insist that they begin doing so.
While high salt levels are bad for plants, things like heavy metals can
be harmful to anyone who is using compost for food plants.

[Robert J Goos]

Susan M. Sanders (ssan...@umich.edu) wrote:

: Ann Arbor, where I live, does regular testing on its municipal compost to

: check the levels of anything that's important for growing, both the good
: and the bad, and copies of the results are made available to the public.
: Ann Arbor compost, at least, does not have high salt levels.

It is difficult to make a compost with a low salt level, when your
starting materials are all "hot" materials (grass clippings, etc.). Grass
clippings with contain 2-3% N and 2-3% K on a dry weight basis. When the
materials are composted, there is a loss of dry matter due to microbial
action, but the minerals (K+, Mg2+, etc.) remain, unless the compost is
leached by rain. I have measured the salinity of such composts, and they
are pretty high (12-15 mmho/cm in a 1:1 suspension).

The problem is when people use such composts, not as a fertilizer (with
maybe an inch or two tilled into the topsoil), but when people use the
compost essentially as a potting soil. I have heard of people filling
beds with municipal compost to a depth of 6 inches, and trying to grow
things directly in the municipal compost. Invariably the
seedlings/transplants fail.

R. J. Goos
C. P. Soil Scientist

[Susan K. Wehe]

I've seen many cases where the seedlings/transplants did just fine, but the
compost was well decomposed and a well balanced fertilizer was used. IMO, the
failures that I've seen were caused by the compost not being very well broken
down and there was little or no nitrogen available for the plants as nitrogen
is tied up in the decomposition process. Many people make the mistake of
trying to use compost for fertilizer when it is better used to feed the soil as
opposed to feeding the plants. We use compost in our window boxes with no top
soil at all and all of the plants are thriving. We do use Osmocote in our
window boxes to provide time released nutrients. If saline was a problem then
I'm sure it would adversely affect our plants as well.

susan

[Renata]

I've always thought (and read somewhere) that shredded mulch acts like a sponge
and doesn't allow as much moisture thorough it to the roots. Chips on the
other hand allow water to run off them down to the roots (as long as it's not
too deep). Cedar is supposed to be long lasting and not termite friendly.

Personally, I use chips (bark and wood) and haven't had any matting problems,
etc. for about the 7 or so years I've been using it.

Renata

In article <6mqoq7$3...@dfw-ixnews5.ix.netcom.com>, ani...@ix.netcom.com
says...

>
>In <35906CFE...@eznet.net> Ja...@eznet.net writes:
>>
>>I was wondering if Pine bark mulch is harmful to certain plants!!!!
>>
>No, but it decomposes very quickly and is not much less than a much
>better shredded hardwood, or cedar mulch. If it is deco bark mulch, it
>can matt down and cause plates to form which are impenetrable by water
>or air...in the longrun, it is not a good mulch to use. I don't
>recommend it. Shredded mulches are superior.
>

>V