Not the sort which forms on the inside of kettles when your water’s a bit on the hard side. That kind is something that simply happens of its own accord. The kind we’ve got is something else entirely – it’s intentional.
We have a little lime tree in a pot. It wasn’t doing terribly well earlier this year, so I dosed it with nitrogen and Epsom salts and compost and mulch, and it perked up a bit. It perked up a jolly lot more when I discovered the existence of scale insects, and gave it a drenching with some organic anti-scale spray.
In due course I moved the lime into a larger pot, and it continued flourishing. But hist! the plot thickens. The ants which had always seemed interested in the lime continued their attentions in the new pot. I don’t usually interfere with the doings of ants who keep outside the house, but this…seemed odd. I suspected. I inspected. I learned the dreadful truth.