The name is given quite aptly here. If you should see an armyworm, then rest not-so-assured that there will likely be hundreds more to follow.
Not exactly ideal news for any farmer. If you’ve never seen an army worm before, we’ll show you precisely what to look for, as well as how to kill them if you do find that you’ve got an infestation.
So let’s assume that you’ve discovered leaf eating worms looking like voracious caterpillars in your precious garden. Now what?
How do you repel these annoyances effectively without damaging your plants or any other beneficial bugs you want to keep around?
Here’s how to get rid of armyworms organically and naturally.
1. Manually Remove Them
One of the best organic options for guaranteed removal and death of the worms.
Physically go through your garden and remove them by hand as you find them.
As you go, carry around a bucket full of very hot, soapy water. As you find them, pick them up and drop them into the bucket.
They’ll most likely die right then and there, but leave them in the water for a little while just to be sure.
As you go around plucking them off, also remove any butterfly larvae you can find.
Once all are removed and/or killed, use Spinosad, a natural liquid insecticide for all types of pests.
The product is made from two kinds of bacteria found in the soil and is also safe to spray on organic crops.
But because it doesn’t distinguish between good and bad insects, you’ll want to remove anything you want to keep beforehand.
3. Predatory Wasps
You can always introduce predatory wasps into your garden, which may seem counter-intuitive, even dangerous. But trust us, this could work.
There are a few varieties you can choose from, such as the braconid wasps, the long-tailed Ichneumon wasps, and Trichogramma wasps.
The second option thrives side-by-side with the critters, with the wasps laying their eggs inside armyworm eggs.
The wasp larvae consume armyworm larvae before they have a chance to hatch.
3. Neem Oil
This is a classic pest removal tactic used by gardeners everywhere.
Neem oil is entirely natural and utterly safe for external use on crops. It both deters and kills an immense variety of intrusive insects.
The only drawback is that rain and extreme weather mean that Neem oil has to be applied more frequently.
Combine 1-2 tablespoons in a gallon of water and pour into a spray container. Add a little liquid soap to make it stick to the plant longer.
4. Bacillus thuringiensis (BT powder)
BT is a natural bacteria that will only harm worm-like creatures and nothing else — destroying their digestive tracts.
This means that virtually any caterpillar is going to find itself regretting setting foot near you once this stuff takes over.
Use it early in the season before they show up. For absolute best effect, use a plant duster for a fine, even layer across plants.
5. Regularly Check for Eggs
Perform regular checkups on your garden and especially keep an eye out for moth eggs. They’ll look like cottony little clumps on the underside of leaves.
Just give them a quick spritz with Neem oil and smear them off into a plastic baggie then toss it into the trash.
You can also slide the eggs off from the leaves and crush them between your fingers.
This is by far the most effective method for small farmers to get rid of army worms as it prevents them from hatching in the first place.
6. Turn the Soil
As you prepare to end your garden for the season, be sure to till any soil you have left to expose whatever pupae might still be hiding.
This will reveal the critters to hungry predators in the area, preventing a further headache for you next season.
7. Set up Bird Baths
Set out little dishes filled with water and a birdbath if you’re so inclined.
Invite them in and show them what a banquet of little munchies you’ve got crawling around.
Most birds will choose worms over crops any day, so feel relieved at the truce you’ve managed to instill for the time being.
8. Homemade Spray
Using such spices as garlic and hot peppers in water, you can make a homemade insect repellent spray that works wonders against army worms.
It can be sprayed where you’ve discovered the little moochers. The spicy solution will kill them.
9. Beneficial Nematodes
These little guys may be weird to think about introducing, but trust us, they’re a real help.
Beneficial nematodes will zone in on the enemies and quickly subdue and eliminate the threat.
Plus, they’ll stick around to help prevent more army worms from staking a claim, so it’s a potentially worthy investment.
10. Bird-Attracting Plants
Take advantage of your feathered friends’ love of all things that wriggle around on their bellies.
By planting plants that attract birds, you’ll encourage them to discover and devour the armyworms they find.
Birds work fast and eat faster, so whatever they find, they’ll devour quicker than you might think.
Plus, as they’re digging down to get their food, they disrupt the soil, upsetting any eggs that might have been laid nearby, helping the process along even faster.
11. Lure in Other Beneficial Insects
This one might seem a bit weird for those on the squeamish side, but this could be one of your better options for getting rid of the critters.
By luring in or releasing insects designed to tackle and devour the array of soft-bodied pests, you’re saving yourself a ton of trouble.
Bring in dragonflies with stagnant water, release praying mantis eggs into your garden, etc.
Either of these bugs is the best natural pesticide you can ask for and they’re fun to watch on top of that.
What are Armyworms?
Now that you know how to get rid of armyworms naturally, let’s learn a bit more about them.
From the Noctuidae family, they are tiny little grub-like creatures that invade gardens and like to hang out on the undersides of leaves during the day.
At night, they come out to munch on your greenery in relative safety.
They’re generously distributed across the United States, especially east of the Rocky Mountains with an expansive schedule of activity throughout the year.
These annoying, soft-bodied little creatures are found on every single continent except for Antarctica, much to the dismay of farmers everywhere.
Considered a major threat in some countries and virtually unstoppable by passive means. This is one insect that farmers everywhere absolutely must take seriously if they wish to protect their produce.
What do Armyworms Look Like?
They come in a wide variety of colors — striped, muddy, greenish, brown, etc.
The trick here is to learn which ones are army worms versus the beneficial caterpillars you’ll want to keep around.
These latter ones turn into the ever-wonderful butterflies, which help to pollinate your garden.
Pictures of the main types of armyworms you’ll want to keep your eye out for are displayed further in this article.
Signs of Damage
Leaves will be chewed apart and if you’re growing soft-skinned fruits and vegetables, you might find minute little holes burrowed into them.
This essentially ruins your produce, as a compromised skin allows bacteria to form within.
The problem is that these leaf eating worms sometimes burrow into the produce to further develop, which is just revolting on its own.
Some also produce a type of cottony substance on the undersides of leaves, further cuing you that they’ve been there.
Types of Armyworms
There are dozens upon dozens of varieties and scientists estimate that well over half of them are severely destructive to all crops in general.
And with so many different species, it’s important to tell them apart from one another.
1. Beet (Spodoptera exigua)
Green and smooth in coloration with dark green pigmentation running along its top and sides. It is also known as the asparagus fern caterpillar.
The beet armyworm is native to Southeast Asia but is found in other parts of the world in countries like North America and Jamaica.
It is one of the most dangerous kinds and they mostly feed on scallion, onion, alfalfa, citrus, grasses, corn, ferns, and ornamental plants.
Like the cabbage looper, they also feed on cabbage, legumes, tomato plants, pepper, pea, potato, sugar beets, soybeans, sunflower, other vegetables, and weeds.
2. Western Yellow Striped (Spodoptera praefica)
The Western Yellow Striped, which, just as the name implies, is dark in color with two narrow yellow lines.
It is commonly found in Columbia, Utah, and California.
They generally feed on crops such as rice, corn, potato, fruits, sugar beet, alfalfa, and sweet potato.
3. Yellowstriped (Spodoptera ornithogalli)
This one can be found all around the Northeastern regions of the US and Canada. However, they have been spotted out west as well, so be vigilant.
It has a much darker color body than the spodoptera praefica, and its markings are also sharper.
The spodoptera ornithogalli commonly feed on soybeans, tobacco, corn, tomatoes, cotton, and alfalfa.
4. Common (Mythimna unipuncta)
They are greyish-brown or greyish-green in color with four large dark spots on the underside of their bodies.
They are a significant menace throughout north, south, and Central America and are also common in western Asia, southern Europe, and central Africa.
The common or true armyworm generally feeds on grass, oats, barley, wheat, and other seed crops.
5. Southern (Spodoptera eridania)
Dark green with a brownish head and normally prominent yellow or white stripes. Commonly found closer to the southern border with occasional pop-ups further north and east.
You’ll likely find these on tomato plants. Other plants commonly affected are cassava, capsicum, cotton, sweet potatoes, legumes, maize, and tobacco.
6. African (Spodoptera exempta)
Featuring a mottled body with varying shades of green and brown, and currently a major threat to crops in both Africa and Europe.
The species mostly targets corn but feeds on other crops such as rice, sugarcane, wheat, vegetables, sorghum, millet, and coconut.
7. Fall (Spodoptera frugiperda)
Fall armyworm has as many as 53 different species in this single category, all ranging in a myriad of different colors and patterns.
Infestation is a major threat in countries like Myanmar, Bangladesh, China, Jamaica, Thailand, Indonesia, Sri Lanka, Laos, Vietnam, Malaysia, Egypt, Japan, and Korea.
Some of the main plants affected include maize, cotton, pasture, vegetables, rice, millet, sorghum, hay fields, and sugarcane.
8. Northern (Mythimna separata)
They mainly feed on corn, sorghum, barley, rice, and wheat.
9. Lawn (Spodoptera mauritia)
Common throughout India, Australia, the Malayan peninsula, and the Pacific islands, the lawn armyworm starts off with a green-pale color.
It then develops a dark green back and with white and brown stripes at its sides.
This type mainly feeds on lawn grasses, oats, and barley.
Armyworm Life Cycle
Eggs are laid in clusters in protected spots that the larvae can consume once they hatch, usually grass or leaf blades.
Once hatched, the larvae become a force of nature, extremely destructive and often moving in large groups in search of food.
They grow up to about 30mm in length and after about 14-20 days, they spend 11-13 days pupating in the soil.
They then emerge as fully grown moths with a lifespan of about two weeks total, ready to lay over 1,000 eggs and begin the destructive process all over again.
Impact on Your Crops
Because they tend to move in large packs, armyworms are regular bulldozers to your crops.
Different worms feed on different things, but to narrow it down, there isn’t any one crop that’s safe from these worms.
Even grass isn’t safe, as the lawn army worm pretty much exists to mow it down. So pay close attention to the types of crops you’re growing and at what times of the year.
This way, you can be best prepared for the possibility of them showing their little faces in your gardens without your consent or knowledge.
The key to stopping an armyworm infestation is to be extremely vigilant about your garden and spotting the minuscule signs before they become a problem that will be too big to deal with.
They’re hard to spot, so it takes a lot of research to understand and recognize the subtle signs as to where they’ve been or where they are.