Tree Problem To Carbon Solution – Day 9 of Low Carbon Living

Long pieces of Eucalyptus bark on suburban pathway

Source: Gill King, Flickr, CC BY-SA 2.0

I’m now well into the second week, with Day 9 of 365 Days Of Low Carbon Living.

This is the first of three posts about turning a problem outside into part of the solution to the unfolding consequences of damage to our climate.

The problem: fallen leaves, bark and wood where you don’t want them

Last week a friend of mine put out a plea to friends: ‘What do you do when you have to spend yet another hour cleaning up leaves, bark and branches from your (neighbour’s) trees?’

Eucalyptus leaves and bark on paving beside garden bed

Source: Gill King, Flickr, CC BY-SA 2.0

If you have trees where you live (and you should!), then debris from the tree can be a problem:

  • It can cause slip and trip hazards, particularly on smooth paths.
  • It can look untidy if it is not in keeping with the ground on which it falls, such as paving, grass, or flower or vegetable beds.
  • It can be a fire hazard in our increasingly long, dry and hot summers.

Some trees shed briefly over a short period – think deciduous trees in autumn or all trees after a wild storm.

Other trees shed shed continually – eucalypts, sheoaks and conifers spring to mind.

And some trees – like the spotted gums (Eucalyptus maculata) where I live – do both: they shed a little all the time, more after a storm, and then shed the bark around their butt (bottom of the trunk) in early January (the middle of summer). It is these characteristics (especially the timing) that, I suspect, provoked my friend’s exasperation.

Bark shed from base of Eucalyptus tree

Source: Gill King, Flickr, CC BY-SA 2.0

Unfortunately, we will only see more of this.

That’s because:

  • One of the things that plants do when it is very hot and/or dry is to try and reduce their stress. They do this by making themselves smaller: smaller = less to lose water. And they do this by shedding leaves, twigs, and (at the extreme end) branches and limbs. At its worst, the heat and water stress kills trees.
  • Our warming atmosphere means more and more hot days and hotter hot days – and more wind, which is drying to plants.
  • A warmer atmosphere also holds more water, which means longer between what meteorologists call ‘precipitation events’ (rain to you and me). That means more time for plants and soils to dry out. When it does fall, rain tends to come in large amounts over a short period of time – so it tends to run off rather than soak into the soil.
  • As a result, soils are generally becoming drier and drier.
  • And all this means that trees around the world are becoming more and more stressed – and so they tend to shed more.

What I do

I use the bark, leaves and twigs from my gum tree as free mulch for some of my paths, particularly under my mulberry tree. I started during the millennium drought. Nowadays I add a little blood and bone from time to time.

The result? Less mowing and a happier mulberry tree.

Bigger twigs and branchlets become rough mulch for my shrubs. Thicker stems provide habitat for small lizards

Tiny lizard crawling over large stick

Source: Gill King, Flickr, CC BY-SA 2.0

Why?

Mulch helps to:

  • protect the soil from erosion
  • add carbon to our soils (on a large scale this is ‘carbon sequestration’ – removing carbon from the atmosphere)
  • maintain soil moisture
    • This helps avoid damage to plants and our built environment from excessive drying cycles and from erosion.
    • It also helps conserve water supplies.
  • add nutrients to the soil and prevent loss of nutrients through water movement (eg erosion) or to the atmosphere via oxidation
  • provide insulation that keeps soil temperatures more even than if there was no mulch
  • keep soils healthy (eg allowing soil organisms to live)

Using tree litter on-site also avoids the pollution, time and money involved with transporting it elsewhere.

Why now?

I mentioned above the stress that trees (and other plants) around the world are already suffering.  In our warming climate, and with soils drying, it is vital that we urgently regenerate our soil carbon sponges so that we can have trees and other plants, with all their benefits, into the future.

The later we leave it, the harder it will be to turn around our current trajectory.

If we ignore safe practices such as this, the now locked-in increased heat under ‘business as usual’ will not only be killing trees but also many at risk people

How

It’s easy: simply gather up the tree litter and lay it where you want it to go.

Mulching is most effective if the mulch is placed on damp soil so you get a head start at keeping moisture in the soil. Heavy, compact mulch can be difficult for water to penetrate.

Applying nitrogen (e.g. blood and bone) from time to time will break-down of hard litter (such as that from eucalypts) for release of nutrients.  It can also help avoid the soil becoming water repellent (‘hydrophobic’).

Breaking up twigs and hard leaves helps keep the mulch neat, reduces fire hazard, helps keep moisture in the soil and helps the mulch break down.  On pathways, this can be done by tramping on it.

The challenge

Can you use all your tree-litter on-site?

Join me!

Any change or challenge is easier if you have company along the way.

So let’s embark on this journey together.

  • Read my blog every day for ideas, thoughts and experiences for living a lower carbon lifestyle, more in harmony with nature – while also adapting to the consequences of our damaged climate.
  • Subscribe to get posts direct to your inbox.
  • Commit to taking action yourself.
  • Add a comment to let me know you’re joining in the effort to turn around our world so it can remain liveable – and what your experiences are.
  • Share with others my posts and what you’re doing – our efforts, progress, experiences and challenges – on Facebook, on Twitter, in conversations with friends, on talkback radio and in letters to the editor.

A problem shared is a problem halved. We’re all affected by the changes to our world so we need to be all in on the action!