by Alana Reynolds (u7118983)

The work we did at Ginninderry was simple. We weeded. We planted trees.

But don’t think what you’re doing here isn’t important, Matthew Frawley, our supervisor, tells us. Those clovers you’re ripping out right now could be the difference between a baby roo making it through next winter.

He is right, of course. Those clovers, for example, make the soil rich with their nitrogen fixing nodes, they grow fast and tall, and their delicate roots are impossible to remove entirely. Known for their ability to help growth in exotic plants, they compete with the native grasses that now have too much nitrogen, not enough sunlight, not enough root space to thrive.

The native grasses provide food and shelter for bees, for birds and mice, and of course, the kangaroos that occasionally pop in from the nearby Box-Gum Woodland Corridor. Without these native plants, these creatures must work harder to survive. Their populations suffer, and we end up with ecosystem collapse. The effects travel down until the whole ecosystem can be disrupted; other species rely on these plants to survive, and these animals are prey for other animals. By taking away that first crucial step, all levels of the ecosystem web are disturbed. With all the threatened species living in that conservation corridor, these plants can mean the difference between endangered and critically so.

Take the threatened Pink-tailed Worm-lizard, for example, who prefer high density of grass. Replace that with clover, and we cause unnecessary stress on their ability to find shelter, and make conditions more difficult for their natural food sources such as centipedes and cockroaches. Weeds cannot adequately substitute the flora that native fauna have evolved to survive with.

Combatting effects of weeds

Construction sites are hotbeds for weeds. We see clovers, crass grass, Paterson’s Curse (notorious for its damage to ecosystems). They hide under construction fences, unreachable, and the seeds blow into the nature strip.

To combat the presence of unwanted seeds, a process called scalping has been undertaken, in which 30 cm of topsoil removed and then replaced. It is impossible to get them all, but each weed removed encourages growth of their native counterparts just a little more.

We plant Australian Tea Tree and Broad Leaf Hopbush. They are chosen for their tenacity and high likelihood of survival; requiring little maintenance, they will thrive despite the clay soil and strong winds. We raise them higher than the soil level to encourage water away from the roots to encourage root growth, to give them the best chance of survival despite the weeds that are sure to return.

Soon, they will provide stability to the soil, shelter to the snakes, food for the birds and mice. They will become part of the landscape, and children will be able to climb on the branches and put the flowers in their hair. They are environmental and social capital.

They are saving our ecosystems, one fed insect, bird, or mouse at a time.