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albert_135

What is your guess as to C:N of a cottonwood tree leaves and all?

What is your guess as to C:N of an entire cottonwood tree leaves and all?

Some part time amateur tree trimmer scammers persuaded a senior neighbor to let them cut down her fine mature cottonwood tree and run it through the chopper.

There is a pile of tons of chopped cottonwood. A handful upon visual inspection looks as if there is more leaves than wood. What is your best guess as to C:N ratio.

Comments (13)

  • 13 years ago

    My guess is that even if it has more leave, it is far more carbon to nitrogen as long as it is coming from a tree, cause from the protein point of view tree leave are considered brown, which is carbon. You might need to add nitrogen to speed things up a bit if you compost it.

  • 13 years ago

    The C/N ratio of leaves ranges from 40:1 to 80:1 and that of wood chips ranges from 25:1 to 600:1. What the C:N ratio of a mixture of wood chips and leaves will depend on how green those leaves are. I know a pile of wood chips with green leaves mixed in will heat up and get quite hot fairly quickly, but the leaves will be gone long before the wood chips get digested.

  • 13 years ago

    46.1 to 152.1 Range

    Freshwater Biology
    Angela B. Moline &
    N.L. Poff
    2008
    Page 1015 Table 1

    I have never seen values above 80:1 before.

    Two other trees were listed:
    Saltceder 31:1 to 83:1
    and
    Russian olive 15:1 to 30:1

  • 13 years ago

    There are many sources of C:N ratios with several different values, The one linked below lists wood chips at 400:1.

    Here is a link that might be useful: C:N ratio of various materials

  • 13 years ago

    Cornell home composting gives sawdust a 200/1 - 750/1 ratio
    I could sure use a load of chipped branches to carbon bulk my piles.

    Curt ;)

  • 13 years ago

    I am all for a perfect/well balance compost pile.
    But I say get the bulk & worry about the balance later,after the city has gone.
    Any C/N mix is better then no compost at all.
    kimmsr Thank you for the LINK.

  • 13 years ago

    ..
    Like Kimmsr says, the leaves will be gone long before the wood is. You'll be composting wood really, not leaves.

    The Cornell University list of ingredients:

    http://compost.css.cornell.edu/OnFarmHandbook/apa.taba1.html
    ..

  • 13 years ago

    Just do not use that or any wood chip mix before it is ready would be my warning.
    The nitrogen sink if you put this in too early could hinder you for at least a year.
    I once put a wonderful looking load of 1/3 topsoil, 1/3 leaf compost, and 1/3 fresh tree grindings from a tub grinder in a new bed 20X40 feet, planted 7 rose bushes and numerous other flowers that instantly died.
    Those grindings grabbed all the N and held it for over a year. It is a great bed now that it has stabilized but EDUCATION does come at a cost.
    For me fresh sawdust or grindings just too much of a unknown to use. Again, my knowledge is little and my patience is none. There-in creates a problem.

  • 13 years ago

    daguvanuh, there's a significant difference between adding the chipped tree to the compost and using something similar as a soil amendment. Depending on how actively one manages the compost, the nitrogen issues are usually adequately addressed - if decompostion is slow or cool, just add more N sources.

    Incorporating the wood chips/tree grindings into the soil limits the available N sources and any plantings will suffer from the lack, although it is pretty easy to compensate for that by adding a high N fertilizer at the same time. Fresh chips or grindings applied as a mulch will have a minimal effect on N availability, generally just at the soil surface, although that may be enough to impact very shallowly rooted annuals and some perennials.

    Mixing the fresh chips into the soil is where you will begin to create problems for your plants, but as stated, you can compensate for this if necessary.

  • 13 years ago

    My-brother-law, one of those hands on, turn it to gold guys.
    Had a fir Christmas tree farm in N.C.. I saw that he mulched his Blue Berries with green saw dust. I told (I was 25)him I had heard that this was a bad thing. He said the small saw mills were all over the hills. That it was not a problem & that he had mulched this blueberry patch for 4 years in green sawdust. Farther more the plants are from Columbia, S.C., they did fine in the mountains, just south of the Tenn. Line.
    I said,"what everyone talking about?", he said "They do not take care of the plants then blame the GSD. for the harm". He put green saw dust around his trees & some of the vegetables.
    I now mulch with what I have & do not worry about a little N lost. Another nursery man said he did not see the problem, if the soil is balanced & lose a little N, it will return in a few months.
    I have no charts or studies to prove this, but both these men have grown plant for over 40 years each.
    The tree farmer got an offer that he could not refuse & sold the whole 275 acre tree farm. He is now grow 8oo acre muscadines vineyard & has a winery in Ga.
    The other is 94 this year & often prove that everything that is written, is not a hard fast rule. I was there I saw it for myself. You do not have to believe me, but I was there!

  • 13 years ago

    I believe you jolj. The recommendations from several University Extension Services recommend putting down 25- 50% more N when using large amounts, 4-6 inches of wood by-products, as a mulch. A joint Oregon, Washington and Idaho blueberry publication also states this and goes on to say that research shows that the N supplementation of the soil microbes needs is drastically lowered after the second year. That cottonwood tree would be basically weed free if part of it was used as a mulch.

  • 13 years ago

    "Mixing the fresh chips into the soil is where you will begin to create problems for your plants, but as stated, you can compensate for this if necessary."

    I really did not do this myself. Contracted and was working for RR. They put the stuff together and used about 20 loads and had some left over. I was hired to haul it away from the site, thus took it home to start a new flower bed. I thought it was great stuff, but did not know anything about a nitrogen sink. Education from that event put me here. I am not embarrassed to say I screwed up but I am not too humble to say THANK YOU to the people here who help those who need some insight when in question?
    In good company here and I appreciate each person's ideas.

  • 13 years ago

    If I had a dollar for every time I screwed up.....

    ;-)

    One saying we have in aviation safety is "Learn from the mistakes of others, you'll never live long enough to make them all yourself."

    Lloyd