I first came across the term ‘Chop and Drop’ in Geoff Lawton’s Establishing a Food Forest DVD. I reviewed the DVD here. Chop and Drop describes the actions of cutting branch wood from fast growing trees ‘nurse’ trees, and then using that wood to feed soil fungi, in order to help the production trees, planted amongst them. Chop and Drop is linked to the use of a more dense tree planting, often fast growing and nitrogen fixing, with many of these trees not destined to remain until maturity.
Chop and Drop at The Sustainable Smallholding
My Coppice was designed in 2008, and planted up in the Winter of 2009/2010. The design for it can be read on the Coppice and Orchard page. Chop and Drop was one of the maintenance techniques that I had planned for, using a close spacing of trees, and the inclusion of Italian Alder for around half of the trees in the planting scheme, and lots of willow too. After four growing seasons the pioneeer trees have grown faster than the main production trees, with the effect being more pronounced in the trees along the Western hedge. Here the trees seem to be benefiting from the shelter of a mature hedge, and potentially from the mycorrhizal fungi here as well. The pioneer trees have been so successful that without cutting them back, the production trees would start to suffer from a lack of late. Time to Chop and Drop.
One of Bill Mollison’s permaculture principles is that very element should perform more than one function, and chop and drop as a technique is no different. The outcomes that I am aiming for are as follows:
- Increase the light available to the slower growing trees.
- Feed the soil fungi.
- Create an instant ‘forest floor’ to provide insects for my chickens.
- Identify whether Italian Alder will pollard.
- Produce some firewood.
Increase Light Levels
The Italian Alder along the Western edge of the coppice has grown to between 12 and 20 feet tall. This is creating shade, wehich in turn has the potential to slow the growth of the other trees, primarily Hazel and Sweet Chestnut. By cutting the pioneer trees back hard, I will increase the light available to these slower growing trees.
Feeding Soil Fungi
One of the phrases that Geoff Lawton uses in his Food Forest DVD is that ‘a forest grows on a dying forest’, or something similar (it’s been a while since I’ve watched it). He’s referring to the fact that a forest has a fungally dominated soil fauna, producing food for trees by decomposing woody material, provided by the trees themselves. When establishing trees into grass, the soil fauna will have evolved to decompose cellulose from grass, and other herbaceous plants, and the decomposers will be a mixture of bacteria and fungi. In order in a natural succession, the woody material will come from pioneer shrubs and weed trees. These grow and deposit woody material which will gradually build up a soil community adapted to a wood/lignin food source. Using pioneer trees in my planting scheme mimics that natural succession, but the addition of chop and drop increases the amount of woody material in the soil, speeding up the succession of soil fauna.
In my Chicken Scavenging System design I describe how I intend to create food for my chickens by creating a woodland floor, providing insects for them to forage for. The trees in the coppice area are at least two years ahead of those in the chicken scavinging system area, so by putting more wood on the ground, I am going to provide a rich source of insects, and some of those insects will potentially help to colonise the chicken scavenging area, which is next to the coppice.
I’m not sure if Italian Alder will coppice/pollard. I can’t remember if I’ve read that it doesn’t, or if lists of trees which will coppice haven’t included it. To be on the safe side, most of the alder has been cut above a branch with active buds, a kind of hard pruning. This has led to some of these trees being cut higher than I would have preferred, as the shade has resulted in the lower branches dying back. I have cut a few of the Italian alder back harder, to below active buds. If these regrow well then I will be able to pllard the remainder in future. If these trees die, then I can adjust my cutting method accordingly.
Originally I had intended to use all of the wood for soil improvement, but a few of the trees have reached a girth worth using as firewood. So although most of the wood will remain in situ, I have put the larger wood aside to use in the house.
Chop and Drop (Before)
Chop and Drop (After)
The picture above shows a section of the coppice area after chop and drop. There is a section behind this one that is yet to be cut, which shows the contrast in height between ‘before and after’. I would have preferred to cut these trees a bit lower down, but as explained earlier, most of these trees were cut to an active bud, just in case the italian alder doesn’t coppice or pollard.
This picture shows a section of coppice floor, and an idea of the quantity of wood added.
The other five sections of this area have not grown quite as quickly as this one, and so I shall leave those and cut them as and when they need it. There is stil a proportion of this coppice section to cut, but only a few hours of work. Some of the production trees haven’t survived here, possibly due to the shade, so I intend to do some gap filling using plants that I have available in pots. These are paulownia, amur cork trees, with a few others available for me to use.