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churchville, ny

These are the numbers from 1 year old leaf mulch compost - looks like a black crumbly soil.(Many maple trees in this area). WHAT DO YOU THINK? Present pH is 7.3, OM is 4.3 I'm adding 15 yards to 6400 square feet. Grew 1338 lb. in 2010

pH 8.1 I thought composted leaves lowered pH
buffer pH 7.4
OM 35.7%
N 37 ppm
P 237
K 2317
Ca 9824
Mg 1377
boron 12
manganese 19
zinc 5
copper 0
iron 2
sulfur 159

CEC 115 K=9, Mg=17, Ca=74

1/7/2011 8:27:38 PM

Williamsport, Pa.

very interesting swaintech, i have plies of the same stuff your talking about, and acess to a mountian of it.i have been adding it to the patches for years.. this year i was gonna hold back on it but i think your post made me change my mind.my om is is around 14% but i think 3 or 4 more inches before tilling shouldnt hurt.

1/8/2011 6:01:34 AM

churchville, ny

Scottie-

I was very surprised at how high the pH was (8.1) because I am already at 7.3. I added some sulfur yesterday to the area.

The calcium # is impressive. Good luck

1/8/2011 11:09:25 AM

Western PA

I would have never guessed the calcium would be that high from leaves. We can now see how compost can be beneficial if one needs to raise the numbers.
Very interesting, thanks for posting this information.

1/8/2011 11:11:08 AM

Willamette Valley, Oregon

Thanks for sharing those numbers. Useful to know for yourself, but I don't think anyone should use those values as a generalization for all leaf litter.

Pure leaf compost should be 75 to 100% OM if the analysis was done correctly. Assuming it was run right, it looks like quite a bit of something else was actually mixed in, maybe some burned leaves (ash) and/or soil?.

1/13/2011 3:01:46 PM

churchville, ny

Bathabitat - Thanks for the comment. I have always used A+L but since U Mass was half the price, I thought I would use them for this analysis - hopefully the numbers are correct!! I was surprised by the OM and pH.

I will double check but I'm pretty sure this is just leaves. All the towns in the county dump the leaves at one location and then a $300,000 machine mixes them until they turn to a leaf mulch - they will not give the mulch back to the towns until it reaches a certain temperature.

I have used the mulch other years with success but have found that I have better results on the 2nd year after incorporating into the soil.

I also had RHINO AND ELEPHANT manure compost analyzed with an OM of 20.9% and a pH of 8.2

1/13/2011 8:21:21 PM

Willamette Valley, Oregon

Maybe those numbers aren't on a dry weight basis, so the "something else" is just water. Reporting on a wet basis seems strange, but some places might do it that way. Still not sure if that is the reason for low OM in a compost sample, but maybe.

For anyone interested here's a good summary of the range of expected values in dead leaves:

http://www.spectrumanalytic.com/doc/library/articles/plant_nutrients_in_municipal_leaves

That table lists Carbon not OM (organic matter).
As a good approximation:
OM = 2 x Carbon, so 50% C is ~100% OM.

It works in reverse too, 20% OM = 10% C

Anyway, hope that helps.

1/14/2011 2:48:27 PM

churchville, ny

Great post, bathabitat - I knew that type of info. had to be out there.

Wow - 400 lb. N, 40 lb. P, 152 lb. K, 656 lb. Ca, 96 lb. Mg in 20 tons is impressive.

I have no idea how many 10 wheel truck loads you need for 20 tons or even what a cubic yard weighs.

I especially liked the large amount of Ca. In 100 lbs. of leaves you would have about 1.5 lbs. of Ca - not bad for being free in this area of the country.

I wish they would have given the pH - I still find my leaf pH of 8.1 hard to believe.

1/16/2011 12:45:33 PM

N.e. Ct.

leaf compost could have a high PH if there is a lot of oak leafs. the indians and pioneers would tan animal hides in barrels of soaking oak leafs. tannic acid comes from oak. in southern New England lake with a slow water exchange have a dark tea color fron tannic acid.

4/8/2011 10:42:56 PM