Need input whether I should chip tree limbs vs burning

[Mark E. Kunnemann]

I live in south central Texas on 21 very wooded acres. I have a plan to thin the trees to open up the canopy for allowing grasses to grow. I have 31 large piles of brush which I had planned to burn, then thought it might be better to chip up for carbon to improve the soil which is sand. I am using some hay and composting goat, chicken droppings which I put in 2 football size clearings which have sprinklers for watering. I know this will be labor intensive, but I am retired and enjoy being outdoors so not a problem. Question do you think it will be worth it?

[Brett Chedzoy]

Wood is about 50% carbon on a dry-matter basis, so there's a lot of carbon in trees - as well as other nutrients.  If I were trying to rebuild the soil organic matter on a sandy soil, I would definitely want to keep as much of that biomass on site as possible.  The more the wood is chipped up and spread out, the quicker it will break down and provide soil OM.  Composting with wood chips with the manure would be much more labor intensive, but may have some net benefits.  I guess that you would need to consult with a soil health expert to help with that analysis. 

Our equivalent here in the Northeast is bale grazing during frozen winter conditions in silvopastures.  The green-up effect from the additional fertility and microbial activity around the bale waste is dramatic. 

[Mark E. Kunnemann]

Thanks Brett that was my thought. Also providing some moisture retention. 

[Brett Chedzoy]

If windrowing or piling the cleared brush and trees vs. chipping and dispersing/composting, you may want to consider ways to use the windrows to your advantage either as internal "fence" divisions or to protect something that is vulnerable.  Here in the eastern hardwood forests we have started to use logging debris - known as "slash" to build "slash walls" (www.slashwall.info) to temporarily exclude deer from young forest regeneration.  I understand that you're trying to clear trees - not grow more trees - but the same concept could be useful to "fencing" an area of improved forages (like alfalfa) that you don't want continuously grazed or maybe even the poultry areas.  Our typical slash wall is too porous to effectively exclude predators like fox from climbing or tunneling through, but I think a wall could be built in a way that excludes most non-winged predators. 

Another option that may be more cost-effective and beneficial down the road would be to turn the woody debris from the clearing into biochar.  There's a local farm that has started to do that at a large scale from slash generated from silvopasture harvests.  I'll upload some pictures and more information on that in a separate post. 

[Mark E. Kunnemann]

Brett that is an excellent suggestion. I have cross fenced some for the animals, but was needing to protect those two large openings. I was considering electric fence, but your suggestion I could move those piles of brush from those openings which I had planned to burn to a long slash pile to act as a barrier. Another consideration is to build kugel culture. I have a slight change in elevation and get some runoff. I have tried this near the house where I trenched and buried some brush and tree limbs with a slight raised area to slow the runoff.

Property when we bought it was so brushy you could hardly walk around and now the goats have cleared most out. The perimeter has been cleared as a burn break and I was having to mow, but the goats are keeping it thinned down. Still looking at my options, but I had not thought about your suggestion. I have a tractor and grapple so moving those piles which I now regret putting in those openings would work. Thanks for sharing and I will keep you updated.

[Scott O'Bar]

I've always heard burning causes nutrients to be lost from the material. Also some carbon floats away in the form of ash/smoke. So my vote is for chipping. Exception would be if you could make bio-char, but that is labor-intensive.

[Mark E. Kunnemann]

I had not mentioned in my original post that I had cut down 80+ trees(oak & hickory) in August/September which I delimbed and left on the ground thinking I would chip up later. I have gathered these up to make a slash windrow around the two open areas on the property to keep the goats out of the seeded areas. Tree trunks were piled up to process for firewood. I have accomplished several projects doing this. Cleaning up the property, building a barrier with slash instead of using an electric fence, and lastly not chipping the material which I can always do at a later date. Wish I could have included more pictures. Biochar is not something I had heard of, but still think I will have to chip at a later date. Thanks for commenting.