As published in the Gulf Islands Driftwood, January 23, 2019, p. 7- also from https://saltspringconservancy.ca/environmentally-friendly-ways-to-deal-with-woody-debris/
With so many branches and trees down from the big storm, it’s important to be Fire-Smart and remove woody debris from areas within 10 metres of our homes before fire season begins. And since a cigarette butt tossed from a car window will easily travel 3 metres, it’s also wise to remove drying deadfall adjacent to roadways. Fortunately, we have 3 months to tackle this before the weather becomes hot and dry, so we can make careful choices about how we clean up.
Smaller twigs with needles ignite easily and are the bulk of what burns during a forest fire, whereas living trees and shrubs need extensive fire exposure before they ignite. Dead branches dry out and become fuel if they are left as they fall, thrown into the bush or stacked in piles.
In contrast, logs, branches and tree litter in direct contact with moist soil will safely decompose and provide important habitat for many small birds, animals and insects. Tucking branches close to the ground in natural hollows in the woods and stomping on them occasionally works well. They remain wet and quickly break down to become humus and feed the forest ecosystem.
Outdoor burning of green woody debris is already causing poor air quality and adding a lot of carbon dioxide and particulate matter to the atmosphere. It also produces dioxins, very potent carcinogens and endocrine disrupters that threaten human health, even at extremely low levels of exposure.
Instead, we can gather many of the logs and branches for use as firewood and let it cure over the summer, stacked well away from buildings. Burning it properly in an approved wood stove or appliance reduces air pollution and provides useful heat.
For those who still burn outdoors, a small hot fire with dry branches will produce significantly less particulate smoke and fewer harmful emissions than a big smouldering pile of wet branches and leaves. To achieve this, branches should be stacked, ideally for 30 days, with airflow allowing the wood to dry and a tarp protecting the pile from rain.
To reduce negative impacts on everyone’s health and the climate, alternative methods of disposal — such as chipping, building berms, making hügelkultur beds and creating bio-char — exist, all with particular advantages.
Cam Proudfoot has been busy at a number of neighbourhood cleanups and can chip large amounts of woody debris in a very short time, if the material is free of dirt and rocks. Cam also has a new machine that breaks up large stumps and root-balls right in place. Chips and needles are useful for making weed-free pathways and for mulching trees, shrubs and garden plants to maintain soil moisture during the dry summer months. This results in healthier plants, with much less water needed for irrigation. Chips shouldn’t be used near buildings, though, as they could create pathways for fire.
Branches and logs can be packed tightly into berms to level uneven ground or create low walls. Berms can also reduce run-off and direct water to areas where topsoil is not susceptible to washing away, thereby controlling erosion and sedimentation. It’s important to keep these moist and/or covered with soil.
Hügelkultur is a method of creating raised garden beds by covering rotting wood with compost and soil. As the wood decays it provides nutrients for plants, increases soil aeration, stores water and sequesters carbon. It can even heat the soil and extend the growing season. Cedar is not recommended, but fir and hardwoods work well. Sometimes rats find hügelkultur beds attractive, so increased rat control measures may be required. Many resources are available that outline how to build hügelkultur gardens.
Woody debris can be used to create biochar, a soil amendment that helps increase soil fertility by making it less acidic, improve moisture retention and provide good habitat for beneficial soil microorganisms. To create biochar, woody waste is burned in an open cavity kiln at a very hot temperature, creating far less smoke than an ordinary burn pile. The burning creates carbon dioxide, but charcoal sequesters carbon in the ground, so overall much less carbon dioxide and no methane is released into the atmosphere, compared to letting wood decompose.
We’re all in this together, and we all need to participate in the cleanup. We can choose methods that safeguard air quality, human health and the environment while helping to keep our island safe from fires this summer.
Written by Jean Wilkinson (SSI Conservancy’s Stewardship Committee), with input from Mitchell Sherrin, Linda Gilkeson, Rick Laing and others