I live on one giant ant hill (actually the entire town is probably one giant ant hill). The “soil” is extremely fine dune sand which you might not think would be good for burrowing but ants, gophers, moles, etc., seem to have no difficulty with their engineering feats. And, of course, it’s dry–especially now.
I am used to dealing with–and swearing at–ants. But my three citrus espaliers have just about got me beat. They are finally coming into their own, the orange is starting to bloom and even the slow-poke mandarin is going to finish its second tier this season. My added grafts are growing out nicely. But the ants are just relentless and their buddies the aphids, mealy bugs, scale–you name it–are everywhere.
If these were free-standing trees I’d use Tanglefoot in a heartbeat. But in addition to the trunks there are also the posts and the fence backdrop. I’d have to put the goo everywhere and I would still not prevent the wretches from climbing onto a stray leaf that happened to touch the fence.
So far I have been using a pyrethrum/oil spray at the recommended intervals but I’m not pleased with how it is coating the leaves and encouraging fungus growth in this damp coastal climate. If I have a really obvious concentration of critters I will spot-treat with something more toxic. I’ve even taken to using a toothbrush and rubbing alcohol on scale when I spot it.
Who does what that actually works without making it better to just buy citrus at the market?
One thing you could try is to paint raw neem on any contact points. Its not a gross sticky mess and it seems to work. I had ants getting into my sprinkler heads earlier this summer and raw neem on the shaft did the trick.
I have both Neem and the Borax powder so I guess I could try a 1-2 punch. I like the Neem idea because–although pricey–I could even paint a band along the bottom of the fence as well as the posts and trunks.
I use Andro Ant Block. It looks like corn meal, and you sprinkle it around the hole. The ants celebrate their wonderful find by dragging it down into the hill, and in a couple days you hear the “dong-bring out your dead” as they start hauling dead carcasses out of the hill and leave them in a little ring around the hill. A day later, all is quiet at the hill.
Terro/borax has worked indoors and outdoors for me. It is completely safe, I use it around my cats (who enjoy stepping in it) and my small children, so that rhetoric should leave you feeling reassured.
I wish all synthetic pesticides could be applied as species specific baits, as is the case for ants. All the poison is consumed by the pest instead of most of it being dispersed elsewhere in the environment as is the case when you spray fruit trees. So I would say that the pesticides in ant stakes and the like will certainly not poison you if you refrain from eating either the poisoned ants or the stakes.
I used to be able to purchase pyretrhoid laced traps with pheromone attractants for oriental fruit moth that seemed to work very well. A tiny amount of poison away from the fruit- what could be better? It was taken off the market.
If most pests could be controlled with these kinds of methods there would be no controversy about the use of synthetic pesticides, IMO, because human exposure would be virtually non-existent and environmental issues would be reduced to almost nothing.
slight side track as this applies to inside your house. When you are at a restaurant or coffee shop grab a few packets of that artificial sweetener that comes in the pink packets. Sprinkle it where you have seen ants. It takes 2-3 days to work on them, then no more ants. I have been doing this for years.