Divot

  • Posted on: 27 January 2023
  • By: MrWurster

I said I would tell my wife what happened if she promised not to laugh. Same goes for you.

This week its been spraying time. My personal preference is to do as little spraying as possible, and with as little use of poisons as possible. But this week it has been blackberries and lacebug, and both have needed something toxic.

The blackberries are old news, we've been battling them since we moved in. The random volunteers that pop up are easy to deal with, once located. Sometimes they go unnoticed for a season or two and then suddenly we are dealing with a spreading bush and its offspring. But the main issue for us is the top olive paddock that once was four metres deep in blackberries. All those monsters are gone, but there are millions of seedlings still coming through.

For the last two years I have been doing test spraying on marked spots to trial the use of a herbicide, to see how effective it is against the blackberries, and any flow on impact on the surrounding olive trees. The results have been sensational. More than 80% of the blackberries have gone in the test areas, and no visible dieback in the olive trees nearby. Of course I am spraying low, coarse spray head with heavy droplets, so its only the specific plant that gets the spray. In the spray tank also goes a wetting agent, and olive oil, turned into a dissolved white oil (although it’s a vivid milky green!). The oil provides stickiness, and in hot weather contributes to the leaf dieback by cooking the leaf in the sun!

So this year it was full steam ahead, and over the last week I have driven up and down, both ways, every row of the main olive paddock and sprayed approximately one billion blackberry plants.


Its quite exciting to drive through a few days later and see the signs of it taking effect….the bright green new leaves on the blackberry plants have a slight wilt, and start to form a black line on the edge. In a few weeks they will curl and die, and then the dieback will work its way down the main vines to the rootstock. Once they die off we can mow and clean the slate.

In the test areas only a few plants re-emerged after the mow. I tackled them again this year, and if we get another 80% success rate they will be almost gone, and next year I hope to finish the job with the remaining bulk of the plants.

Some blackberries grow at the base of the tree. I can't spray them. Previously I've trudged around the paddock for days in welding gloves and pulled them out by hand. This year I realized if they are long enough I can stamp them down away from the tree and spray most of the vine without touching the tree.

Because it’s a downwards spraying job, the wand mostly no more than knee height, and I spray from a buggy, I don't need the full spray suit. Which is a relief because its been warm in the sun, and wearing a plastic suit is no fun.

But the other spraying job is upwards, through the trees, a fine misting spray. For that I need a full protective suit, breathing mask, gloves and boots, and I drive around in the sun slowly boiling alive. Its lacebug season. The telltale signs are there, and I should have started spraying a couple of weeks ago. But I underestimated how much progress the lacebug had made. I started out by marking the trees I sprayed, but it didn't take me long to realize it was quite widespread and I was tackling almost every second tree.

For lacebug we use a basic pyrethrum spray, and if its not too hot, the olive oil/white oil. In fact the oil is almost enough. It suffocates the lacebug on the leaf without needing the poison. But in this weather, an oiled leaf will cook and I would end up damaging too much of the tree's leafstock.


Here's what we are looking for...a clump of browning and dying leaves

Fortunately lacebug starts on the lowest branches and spreads up and out. Its possible to drive around and spray the visibly affected low branch. I often have to stop and pull out the hose and walk further than I can reach from a sitting position. That's not good, as it means the lacebug have duplicated more than once and we are not far from a population explosion.

Turn the leaves over and you can see what's causing that dieback.

So, that's done. We have four separate groups of olive trees, and all had different patterns of infestation. The ones on the laneway out to the main road, all the trees facing south were where the infestation was. Clearly they have blown down the valley from somewhere else. In the main paddock there is a row of table olives. There is always a tree zero amongst them, and the lacebug ripple out from those trees.

But in the bottom paddock there were quite large colonies, smack bang in the centre of the grove. How did they get there? I suspect they wintered over. That paddock is the least susceptible to frost and I think its the proximity to the moving river water moderating the temperature. Good for the trees, the fruit....and successive generations of lacebug.

So, driving around looking up at the tree canopy, I ran over the spray unit hose which had dragged itself out of the buggy. Its happened before,. Not a good thing, and something I look out for, but it happened. It pulled the hose out of the pump, dislocating the rotating socket where it connects. I assessed the damage. The electrical leads to the pump had severed and needed to be rejoined.

Looking at the rotating socket, made of a hard plastic, the simplest option was to whack it back into place. No tools in the buggy as I clean it out before spraying so nothing gets contaminated. The tailgate on the buggy is flat metal. Why not…..I propped the fitting in the opened tailgate and slammed it shut.

Remember…the deal was you won't laugh.

When I slammed the tailgate shut the fitting twisted, and trapped my thumb. Very painful. I was wearing a heavy glove, inside that a rubber glove. I figured I'd be looking at a massive blood blister. I took the gloves off and gasped. I had gouged a massive divot of flesh out of my thumb.

The flesh is gone, there's nothing to stitch up. I'll have to keep it clean until it heals over. Every time I touch something I wince.

Lucky I was wearing a glove!