Watering revegetation
Our annual revegetation program includes both direct-seeding (sowing the seed into the ground) and infill planting of tubestock. We focus on semi-arid woodland species, particularly key canopy species which have insufficient reserves of seed in the soil to allow them to establish on their own.
Right now, it’s pretty hot: it has been around 40 for the past three days and another 40 degrees forecast for tomorrow. We’ve only had 35 mm of rain during the last three months of real heat. But this weather is to be expected during Summer in the Victorian Mallee, and that’s why we provide regular water for the trees and shrubs which we plant.
We used to follow the old-school method: plant on the Autumn break and then water once per month during the first Summer. But we had such high losses that we’ve decided this approach is no longer suitable for our changing climate. The first good rains of Autumn (the “break”) is getting later, meaning we were planting almost in Winter, then the plants would struggle in the frosty cold, before being hit increasingly often by a dry Spring. The little plants would be poorly established and many would die in the first summer, even with supplementary watering. It was very depressing.
So now we plant as soon as the worst of the heat is finished, watering deeply when we plant. Then we continue to water if the Winter and Spring is dry to ensure the plants can grow strong roots and shoots before the Summer heat arrives. We’ll continue to water through the first Summer, every fortnight if needs be. And, this is most important, we celebrate the survivors, rather than lamenting the losses. You’ll hear me wandering through the revegetation shouting “It’s alive!!”. Try it. I promise it will help you if you are carrying out revegetation in a tough climate.
The 900 L refill tank and the bike to ride back and forth
The 400 L watering tank with the”automatic” watering arm.
Of course it helps if you have a good watering system and Phil has it down to an art-form. He takes the 900 L “refill” water cart out to the paddock with the ute, then rides the bike home to pick up the 400 L water cart and four-wheel motorbike. The 400 L cart has an “automatic” watering system (really, it’s just a pipe on a pulley but it’s pretty effective to deliver the water). So Phil can put out 1300 L of water (at 10 L per plant), before he has to return home to refill the two tanks. It’s laborious so we don’t plant as many tubestock: about 300-500 per year until we can figure out how to clone ourselves.
We’re always on the lookout for alternatives to watering, but unless we only plant in a La Nina high rainfall year (and who can predict that!), watering seems to be unavoidable. Our annual rainfall is less than 300 mm, and often much less: 144 mm in 2018, 189 mm in 2019 and 281 mm in 2020. The cocoon planters, which I wrote about here, are very promising but a bit expensive for large-scale, privately funded revegetation. So, for now it’s the slow and steady progress of planting and watering - these tubestock are 20 months old (that’s pretty good growth for the Mallee!).
