I will look out for that, thanks could be a handy product for here! The Lucerne tree does have shade cloth around and over it, to stop the ducks getting to it but it is still a warm spot despite that. If it does die, I can probably offer to trim the neighbours tree for him and feed that to the ducks.
It looks like some plants are starting to suffer a bit in the heat today. It's been a pretty good run though, the soil has been well set up to handle it. More mulch out today. This week will be 40C so I will be back to watering every chance that I get.