Is it just me, or are there more ants around than there used to be?
I frequently get questions from anxious garden-owners, fretting about the large bumps ruining their lawns: and certainly I would say that over the last few years, I have seen more and more of them myself.
So what's going on? What are they doing? Well, they are building homes for themselves by creating a complicated system of galleries, which are tunnels and chambers, underneath the ground. To do this, they excavate the earth and take it up to the surface. As the surface rises, the bare ground is able to absorb heat from the sun, and the whole thing becomes a sort of organic storage heater. Inside the heap, the worker ants move the eggs, larvae and pupae around as the sun moves, in order to keep them in the warmest part.
Unfortunately, in doing so, they ruin our lawns.
So what can we do about them? To encourage them to go and nest elsewhere, keep the grass cut short, and keep running about on it: the galleries are fragile in the early days, and a lack of disturbance is vital - the mounds cannot form in frequently mown areas. They are also vulnerable to damage by erosion and compaction by trampling, so get out there and dance under the moonlight!
If you prefer chemical warfare, get out the ant powder and dust the tops of the hills lightly whenever you find them. Use a hand tool to fluff up the soil, and if you find ants, dust them. If not, spread out the loose soil and dust it anyway, then work it down to ground level by gently brushing the grass to and fro. The idea is not to smother the ants, but to produce a well-dusted zone that they can't avoid walking through. Each ant picks up a light coating of the ant powder, then walks it back inside the nest - ants never wipe their feet
If it's wet, or if you have big lumps, use a trowel to make two slits about 4" long at right angles to each other, then lever up this "flap" to reveal the horrors below. If it's teeming with ants, apply powder, put the flap down and stomp it flat.
As for the lawn lumps, have a midnight chanting, stomping party! As soon as they start to appear, do the slit-and-powder, and stomp them flat. The longer you leave them, the worse they will get so it's worth flattening them as soon as you spot them. The more activity you have on the lawn, the less chance the lumps will have to grow out of control: firstly because you will spot them and powder them, and secondly because you will be physically flattening them.
So, make stomping round your lawn part of your daily routine!