Anthills at the base of all of my new fruit trees!

Hi everyone, it’s been a little while since I last posted as we’ve been swamped with the process of our house build.
Just before Covid 19 hit, we had planted out 15 or so potted and bare rooted fruit trees on a southwest facing slope. We didn’t treat the terrain of the slope pre-planting, just removed a bit of the vegetation on the spots where we wanted our new trees, dug holes and mixed the heavy clay we dug up with some compost to improve the soil slightly where the new tree would be planted. Then several months passed as the quarantine prevented us from travelling to our property. Now that we’ve been able to go back we’ve obviously noticed lush vegetation everywhere on the field, but on the places where we planted our trees and the soil had been disturbed, the soil remained baren and no plants had come in to grow yet (eventhough I had sown in wildflower seed mixes after planting the trees). Instead, it seems like an endless supply of ants have moved in instead. Of the 15 or so trees we planted, nearly half of them have an anthill at the foot of their trunk. Some anthills are next to the trees, others actually have been built around the tree, as if the trunk of the tree acts like a center tentpole for their hill.

Now I don’t have a problem with ants per se (although it is a bit annoying when tending to the trees to avoid stepping into an anthill), but I was wondering if the anthills being so close, or engulfing the treetrunks could damage the trees (maybe they dig into the roots, or damage the trunk?). Alternatively I could imagine that such an amount of ants close to your trees could also keep potential other critters away from nibbling at my trees. I don’t think snails would venture on my trees if they have to cross an active anthill first. I can also imagine that the tunnelling of the ants into the ground can also help breaking up the compact clay soil.

I don’t have a lot of knowledge about ants (except that I stepped into an anthill barefoot when I was a child and did not like that experience at all!), so please enlighten me with your knowledge! Are these ants a problem for my tree, or are they actually useful?

Do the fruit trees have aphids?  Ants love to use my cherry and plum trees as aphid farms.

I had an apple tree that almost died because I had the same happen. An ant hill started around the whole base of the tree and as it was built up the bark of the tree that was covered by the ant hill started to rot and peel away from the trunk. Kind of what would happen if mulch was placed to close and to high on the trunk. I would try and get rid of those ant hills.

If you see trails of ants climbing the trees then you mostly have aphids.

Anyway, I would not like ant mounds near my trees.

Usually controlling the ants may take care of an aphid problem.

Here are some threads on controlling ants:

https://permies.com/t/67661/Ongoing-battle-ants#570673

https://permies.com/t/124185/Coffee-grounds-confused-good-bad#992274

I did notice some aphids on some of the trees. Are the ants sustaining the aphids in the trees?
Is it best to use spent coffee grounds or fresh ones? And will the coffee hurt the trees? I’ve heard that the caffeine and the acidity of the coffee can damage your plants. But I’m not at all experienced on the matter.

Isn’t it possible to scoop up the mounds with a shovel and deposit them far away from the trees?

Went back to the property armed with coffee. Turns out I was majorly unprepared to deal with this amount of ants! After scything the grass around the trees some more I discovered anthills everywhere. Either this Is one big colony taking over the entire slope, or ants are really keen on living on my property!
I’ve also discovered 2 different species. Small black ones and big red ones. However from the big red ones I couldn’t discover where they were coming from.

I decided to scoop up the tops of each anthill I came across, especially the ones growing around my trees and then sprinkling a layer of coffee over the exposed colony and watering it. I hadn’t nearly enough coffee to deal with all of the colonies so I’ll have to go back to add more. But I’m slightly worried what such an amount of coffee will do to the acidity of my terrain. What’s the point of saving my trees from anthills but then poisoning them with the acidity of all of that coffee?
I’ve tried finding Borax in our local shops, but nobody even seems to have an idea what I’m even talking about.
Anyone know where to find borax in Europe/ Italy?

Your trees look super healthy!

I have an ant hill at the base of one of my fruit trees, and it seems to be actually making the tree healthier.

I also have some veggies growing near and out of the ant hill, and they are among the most healthy plants of their kind. I tossed some seeds onto the ant hill on purpose when I planted them just to see how they would do.

Was also reading the other day on how ants prey on and can help control a large amount of fruit tree pests.

As long as the ants don't overwhelm everything, I'm planning to let them have their place in the food forest.

I agree with Steve, but it depends on the ant type. We have small "sugar ants" who seem to set up small colonies where there is a source of sugar, then move when it is gone or they get wet. These colonies are way too small to mess up a root system.

But there are some giant colonies that might dry out the roots pretty thoroughly with a young plant. I planted mint around some trees and it worked- but now I have mint. Everywhere. I would maybe go with an oily mint family plant that is not as aggressive about spreading. I am trying monarda and oregano now.

Steve Thorn wrote:Your trees look super healthy!

I have an ant hill at the base of one of my fruit trees, and it seems to be actually making the tree healthier.

I also have some veggies growing near and out of the ant hill, and they are among the most healthy plants of their kind. I tossed some seeds onto the ant hill on purpose when I planted them just to see how they would do.

Was also reading the other day on how ants prey on and can help control a large amount of fruit tree pests.

As long as the ants don't overwhelm everything, I'm planning to let them have their place in the food forest.

To be honest what you’re saying was my initial thought as well, that the ants might actually be beneficial in keeping off other pests from our trees, because what insect wants to mess with a bunch of ants?
But then a lot of people were telling me I should get rid of them because they could damage the trees, so then I got worried about losing my trees. And now I don’t know.
I’ve scooped of the tops of the anthills, and while I think that will have slowed them down a bit, I don’t think I’ve killed the colony. I think I will now just keep an eye on things to see how things develop.

Steve, do you think this sticky sap on my peach tree could be caused by ants?
I’ve also spotted some leaf curl on my apricot, cherries and pear.

S Bard said "But I’m slightly worried what such an amount of coffee will do to the acidity of my terrain."

I use spent coffee grounds.  I would not be concerned about the acidity of your terrain.  The coffee grounds add nutrients and will attract earthworms. Think of it as food for the earthworms.

I also use a 50/50 solution of vinegar/water to kill ants.  It only works where the vinegar is poured on the mound and what is saturated.  I recently used it and only poured it on half of the mound so the mound is still active where the vinegar did not saturate the soil. I know nothing about vinegar and how it affects plants and trees though we used it to improve the blooming of gardenia plants.

I have also read that cornmeal will kill the ants because they are attracted to it and cannot digest it.  I have not tried this method.

Like the others have said, I don't worry about ants in my trees unless I see them causing a problem.  Though if those are aphids on your trees that might be a concern since ants farm aphids.

Steve Thorn wrote:Steve, do you think this sticky sap on my peach tree could be caused by ants?

No worries, the ants shouldn't cause any damage like that. I bet it's probably either borers or most likely a minor disease issue, I'll go post over in that thread about it.

I’ve also spotted some leaf curl on my apricot, cherries and pear.

I wouldn't worry too much about it this first year, since the trees are probably just going through a little transplant shock in getting adjusted to their new home, especially if they were potted trees grown in a greenhouse by the nursery, where they were probably fertilized, maybe sprayed, and given a daily supply of water.

If you have significant issues next year, it may be more of a concern, but I wouldn't worry too much if it's just small issues this year.

I almost forgot, another helpful item for ants and slugs is little piles of rocks around the trees. These provide habitat for amphibians and lizards.

Also snakes so beware, but that has cleared up the aphid issue on a few trees.

I'll just advise against using borax. You could easily poison your ground with too much boron by using borax. When treating a boron deficiency, borax can be used at minuscule rates; something like a teaspoon per hundred square feet. If your soil already has plenty of boron, even that amount might be toxic.

I've found that heavily watering ant hills will discourage them, particularly if you have a jet setting on the hose.

Borax:  I believe it's not sold in Europe by law.  It's not sold here in Britain, although I was able to order a small amount online once (but it was pointless to buy so little as I wanted it for laundry).