“I have a number of fire ant mounds in my Asparagus and i’m not sure what to do about them. I don’t want to damage the crop or put something on it that will be harmful to people. Suggestions?
First of all, let me give this disclaimer: I live in Wisconsin and we do not have fire ants here! What a blessing! However, I have studied them in the past and have done a bit of research. It is amazing what different people recommend.
Fire ants are no mere pest—as anyone who has accidentally stepped on one of their mounds will tell you, a fire ant’s sting can be painful for weeks. Gardeners who have tried to get rid of fire ant colonies know there is no shortage of advice on how to get to eliminate the mounds, but few truly effective methods. But does that mean you need to turn to a toxic solution? Thankfully, the answer is no! Here are a number of methods you can use to extinguish the fire on those ants!
1. Orange Essential Oils
Oil from the peels of oranges is completely safe for humans but deadly to fire ants – it dissolves their exoskeletons. Recent studies have discovered that orange oil solutions are effective in decimating fire ant colonies and, if the solution reaches the queen, destroying the mound for good. The key here is pouring enough solution to thoroughly soak the mound, and pouring at a time of day when ants are in the mound.
Some studies also show that molasses or compost tea used in conjunction with orange oil may enhance the effects. A drop of soap in the orange oil solution helps it to mix with the water.
Orange Oil Recipe for Fire Ants
6 oz. orange oil
1 tbsp blackstrap molasses
a squeeze of liquid dish soap
Add to a gallon jug and fill with water.
Drench the mounds when the ants are not out foraging. Fire ants prefer mild temperatures, so in the summers they may be out early in the morning and hiding in their mounds by mid-day, and vice-versa for cold days. A gallon will thoroughly soak one mound. There will be no effect on the asparagus from this recipe.
You can purchase bottled orange oil (look for Essential Oil of Orange or D-limonene) and use the above recipe, or pick up a product with orange oil that has its own dilution instructions on the container.
2. Bucketing fire ant colonies
If you are a bit daring, this is one of the simplest ways of dealing with one or two problem colonies. Basically, the procedure is to rapidly dig the mound and a foot or so of soil under the mound and dump it into one or several large buckets. Sprinkling the bucket and shovel with baby powder or cornstarch before you starts keeps the ants from climbing out of them. Remember to tuck your pants into your socks to keep the ants where you can see them.
Dig up the soil at a time of day when most of the colony is in the mound. Once the ants are in the bucket, you can choose to drown the ants or simply to carry them to some place where they are not a problem. If you choose to drown the ants, add a generous squirt of dish soap, water from a hose, and stir to mix the soap throughout the mud in the bucket. The soap breaks the surface tension and drowns the ants much more quickly. It usually takes overnight to kill the ants. In the heat of the summer, they will probably drown faster, but on cool days in the spring, it may take longer. It is best not to fill the buckets more than three-quarters full of ants and dirt so there is room to add the water.
PLEASE NOTE: I personally would not recommend digging them up. I don’t want to hear that you ended up in the hospital. Of course, some people (probably my husband) would opt to go this route and would be quite successful in it. Others, like me, would not be. Also, digging may damage the asparagus plants (depending on the proximity of the hills to the plants).
3. Hot water
Pouring hot water on the mounds is effective and environmentally friendly, but may require 3 or 4 applications to kill the colony. Water should be at least scalding hot, but does not need to be boiling. This works best when you use 3 to 4 gallons of water in each application. WARNING: Hot water kills asparagus and other plants and may cause severe burns if spilled. If the hill is far enough away, this may work.
4. Straw itch mites
Some studies have shown moderate benefits from releasing these beneficial mites, but other studies have found none. However, the most dramatic effect has been the large rashes that researchers have gotten from some of the stray mites that they were releasing. Ooh, itchy, itchy, ITCHY!
Some also recommended corn grits and dry rice for the ants to eat and bloat up with when they drank water. This cannot possibly work, as adults eat only liquids and larval digestive tracts mix food with saliva to digest it. Other poorly working methods include diatomaceous earth, mixing different colonies together, gasoline + match, household cleaning products, anteaters, sonic pest deterrent vibrators, and exhaust fumes. Various accounts prove that these methods do not work.
I hope you have some success with the four methods given here. Let me know how it works out!
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