Milkweed Bugs

We all know that Monarch larvae eat Milkweed plants, but there are other insects that also use Milkweed as a source of food. We must realize that most of these insects serve a purpose within their respective ecosystems. It is important to remember that species diversity is necessary for a healthy ecosystem. Feel good about providing habitat and resources for another species in your garden.

The reason that many of them are black and orange like Monarchs is that they use the same defense mechanism called “aposematism” where their black and orange coloration warns predators of their toxic/bitter taste caused by cardiac glycosides which they acquire from milkweed plants they feed on.

​Here are some of the insects you will find on milkweed:

Red Milkweed Beetle (Tetraopes tetrophthalmus)

Distribution: Their range matches the distribution of Common Milkweed (Asclepias syriaca), basically the Northeast quadrant of North America.

Harmful to Monarch caterpillars/eggs? No. They are herbivores and only eat milkweed. They are harmless to monarch larvae and eggs so you can leave them on your milkweed plant if you have enough to go around. The best method to remove the bugs from your milkweed plant is to grab them and throw them into a bucket of soapy water.

Identification: Red/orange in color with oval spots all over the body and un-ringed antennae.

​Life Cycle: Eggs laid on stems near the ground or just below the surface; larvae bore into stems, overwinter in roots, and pupate in spring; adults emerge in early summer.

Small Milkweed Bug (Lygaeus kalmii)

Distribution: Throughout the US and Southern Canada.

Harmful to Monarch caterpillars/eggs? Sometimes. They are mostly herbaceous and will suck nectar from flowers and sometimes feed on milkweed seeds. However, they have been reported to be predators, especially in spring when milkweed seeds are scarce, feeding on Honey Bees, Monarch caterpillars and pupae, and Dogbane Beetles, among others.

Identification: They adult is black with a broad orange/red band on the forewing, forming an “X” shape. Their head is black with a dull red spot on top. In eastern specimens, forewings are all black, but western specimens have large white spots. (

Life cycle: Eggs are laid on Milkweed in spring, one or more generations per year. Adults overwinter.

Large Milkweed Bug (​Oncopeltus fasciatus)

Distribution: Throughout North America and from Central America through Mexico and the Caribbean to southern areas in Canada.

Harmful to Monarch caterpillars/eggs? No, they do not feed on Monarch larvae or eggs so they are harmless and play a role in the ecosystem. However, they do feed on the seeds, leaves, and stems of Milkweeds (Asclepias spp). Damage to the plants can deplete resources for Monarch caterpillars. You can control their population by removing the seeds pods from the milkweed plant.

Identification: Adults are overall black and orange with a black band in the middle and two large black spots in front and back.  Nymphs are bright orange and develop black spots late.

​Life Cycle: Eggs are laid in Milkweed seed pods or in crevices between pods. About 30 eggs are laid a day, and about 2,000 over a female’s lifespan, which lasts about a month during the summer. One or more generations per year. They can’t survive cold winters, so they migrate south in the fall. They overwinter in the southern Atlantic and Gulf coast states where they feed and breed and gradually migrate north again in the spring and summer.

Swamp Milkweed Leaf Beetle (​Labidomera clivicollis)

Distribution:  Widespread in North America east of the Rocky Mountains, south to northern Mexico.

Harmful to Monarch caterpillars/eggs? Technically, no, because they are herbaceous. However, they do feed on milkweeds, especially Swamp Milkweed (A. incarnata) and Common Milkweed (A. syriaca). To control populations from eating all of your milkweed, you can pick them off and put them in a soapy bucket of water.

Life Cycle: They often overwinter as adults among leaves such as Mullein (Verbascum). Adults mate on or around milkweed. Eggs are cemented to the underside of leaves. Larvae feed on leaves and drop to the ground to pupate.

Milkweed Tussock Moth Caterpillar (Euchaetes egle)

Distribution: It is found from southern Canada and south through Texas and Florida in North America.

Harmful to Monarch caterpillars/eggs? No, they are herbivores and only eat Milkweed. But they can defoliate an entire stand of Milkweed in a matter of days. You can try removing these fuzzy little guys by hand if you are concerned that there will not be enough milkweed left to sustain your monarch visitors and are determined to reserve your supply. However, handle milkweed tussock moth caterpillars with gloved hands as the caterpillars have urticating hairs that can result in an uncomfortable rash.

Identification: Early instars appear slightly hairy and gray. Later instars sport tufts of black, white, and orange (sometimes yellow) setae (hairs). The head capsule is black. Larvae grow as long as 35 mm.

Life Cycle: There is one generation per year in the north and two or more in the south. Mature caterpillars occur from June onwards.

Milkweed Tussock Moth (Euchaetes egle) caterpillars are gregarious when young and feed in large clusters.

Milkweed (Oleander) Aphids (Aphis nerii)

Distribution: Throughout North America and from Central America through Mexico and the Caribbean to southern areas in Canada.

Harmful to Monarch caterpillars/eggs? No, but if they become abundant they will suck the life from Milkweed. They also leave behind a trail of sticky, sweet honeydew that attracts Ants, Wasps, and other sugar-loving insects.

Identification: Tiny bright yellow insects with plump, pear-shaped bodies with black cornicles and legs.

Life Cycle: The Oleander aphid reproduces entirely by parthenogenesis (without fertilization). The females are also viviparous, meaning that they do not produce eggs but instead give birth to live young called nymphs, the adult female’s clones.

A recently released study suggests that monarchs are more likely to survive on milkweed shared with non-predatory insects than on a “clean” plant. They believe this is because the plant has more food options for a predator, which lessens the chance that they go after the monarch. In other words, we might be doing more harm when we try to kill or remove insects we find on milkweed.

My suggestion is to grow lots of milkweed so there is plenty to go around. You can never have too much milkweed!

Find milkweed seeds to purchase here:



One Step at a Time

In July 2014, I accepted a position with Peace Corps Response as a volunteer in El Salvador working at a butterfly exhibit as an Educational Butterfly Farm Management Specialist. My job was to train a few people to cultivate butterflies and to maintain a healthy habitat for them inside the exhibit.
The map of El Salvador showing the Departamento de Morazán where I served as a Peace Corps Response volunteer.

El Salvador is still recuperating from a devastating civil war that wracked the country from 1980 to 1992, leaving at least 75,000 people dead and tens of thousands more displaced. The site where I served as a volunteer, Segundo Montes, is a community made up of five towns in the eastern department of Morazán. Segundo Montes was formed in 1990 by repatriated refugees who’d fled the country’s civil war. After nearly a decade in refugee camps in Honduras, residents returned en masse 28 years ago to reclaim their livelihoods and dignity.

There is a concerted effort to develop tourism along the Ruta de Paz (Peace Highway) from Morazán’s capital of San Francisco Gotera to El Salvador’s border with Honduras, along Highway 7. The butterfly zoo is strategically located along this route and is well-positioned to attract the attention of vacationers headed to the cool air and brilliant sunshine of Perquín, eight miles farther north.

Teaching visitors about butterflies inside the “Mariposario” butterfly exhibit.

Within a few days of arriving at the site, I, along with my local counterpart and a couple of youth volunteers were driven up the mountainous Ruta de Paz to a small town called Arambala. We were tossed about inside the jeep as we traveled over a rough road to an area where the tiny village of El Mozote once stood. El Mozote is famous today because a beautiful memorial stands in its place to honor the 1,000 civilians, mostly women, children, and elderly men, who were massacred during the civil war.

The Mazote memorial features Christ, speaking John 14:27 as recorded in the New Testament, surrounded by martyrs such as Gandhi, Bishop Romero, and Martin Luther King, Jr.

We climbed out of the jeep with our butterfly nets and backpacks. A small frail-looking granjero (farmer), wearing a worn straw cowboy hat with a machete hung on his belt, met us and proceeded to escort us down a quebrada–a ravine–where apparently we would be able to find some butterflies to capture and place in the butterfly exhibit. We were particularly looking for Blue Morpho butterflies and Malachite butterflies because they are rather colorful with their blues and greens.

The Jeep brought us to the top of a mountain in search of butterflies.

I kept slipping and sliding as I tried to navigate down the steep and narrow path. The anciano (elderly man) seemed not to have as much difficulty as I negotiating the trail, so I figured if he could manage, I could too. As I laboriously climbed down through the thick vegetation, I realized I was eventually going to have to climb back up. I had been living in Florida for most of my adult life and had not climbed a mountain in years! How was I going to manage? My knees were already aching. The farther we descended down the mountain, the more worried I became. I could not imagine myself being able to hike back to the vehicle. I was so worried that I could not enjoy the beautiful lush scenery.

Thick vegetation surrounded our path down the hill.

Eventually, we came to an area that opened up and leveled out where an abandoned and dilapidated adobe farmhouse stood. The surrounding area was thick with large mango trees, banana trees, and old citrus trees. I was relieved not to have to negotiate the steep trail, but now I kept fumbling as I tried to walk through the overgrown garden.

Trying to catch butterflies with a net in the thick vegetation.

As I staggered through the vegetation I was elated when I saw several butterflies flying overhead. Vladimir Nabokov, the author of Lolita, once said, “The highest enjoyment of timelessness is when I stand among rare butterflies and their food plants. This is ecstasy, and behind the ecstasy is something else, which is hard to explain. It is like a momentary vacuum into which rushes all that I love.” I, like Nabokov, was caught up in that timeless ecstasy as I surveyed my surroundings and looked upon all the beautiful butterflies. I completely forgot about the anticipated climb back to the vehicle.

Many butterflies tend to fly very fast and erratically as a defense against predators such as birds, so they can be quite challenging to catch with a net. It’s easier to catch a butterfly when it stops to nectar on a flower. Some butterflies, such as the Blue Morphos and Malachites, do not stop to nectar on flowers. Instead, they feed on fruit.

The Malachite (Siproeta stelenes) is named for the mineral malachite, which is similar in color to the bright green on the butterfly’s wings. Typically, the wingspread is between 8.5 and 10 cm (3.3 and 3.9 in). The Malachite is found throughout Central and northern South America, where it is one of the most common butterfly species.

I carefully plodded through the thick undergrowth towards some flowers by a tree, hoping to catch some butterflies. I did not see that there were Malachite butterflies feeding on the fallen mangoes beneath my feet until they all fluttered to escape my intrusion. I was encircled in a cloud of emerald-green jewels. It was magical! I began to giggle with sheer delight. Distracted, I failed to catch a single one of those butterflies with my net.

I began to wonder if these butterflies represented those precious children who were massacred years ago. Many indigenous Central American peoples believe that butterflies are the souls of their dead ancestors. For example, in Mexico, the natives in Michoacán State believe that the Monarch butterflies that return to their homeland mountains every year around the Day of the Dead celebrations in early November are their ancestors returning to visit them. Did the souls of these Salvadorian children return to their homeland as butterflies?

This statue represents the children who lost their lives.

My compadres and I did manage to catch many butterflies that day. We protected them in envelopes nested in small boxes inside our backpacks. Once we had enough butterflies, we began our trek back up the mountain, which, as I anticipated, was even more challenging than the hike down. Again the weathered old man led the way. I was huffing and puffing and working up quite a sweat, trying to keep up.

After a while, he turned around to encourage me and said, “Slow and easy, one step at a time. You will make it. We do not need to hurry.” He then began to tell me his story. He was living with his wife and thirteen children in   that abandoned farmhouse when the civil war started. After the massacre at El Mozote, he realized he needed to escape, along with others, to a refugee camp in Honduras to protect his family. With just a few clothes and possessions, leaving their home and farm behind, they began the long arduous journey through the mountains to Honduras. I could imagine him leading the way and stopping every now and then and turning around to his children and saying, “Slow and easy, one step at a time. You will make it. We do not need to hurry.”

Painting depicting families trekking back from Honduras to Segundo Montes, Morazán, in El Salvador.

I did survive the trek up the ravine thanks to the old man’s reassuring words of encouragement and his persistent example. We stopped by the memorial at El Mozote. The memorial stands on top of a hill surrounded by lush green fields and beautiful mountains. Statues of Martin Luther King, Jr.; Mother Teresa, Pope John Paul II, and Mohandas Gandhi were all represented. I felt privileged not only to be surrounded by great leaders who taught me how to overcome adversity but proud to be standing next to an old Salvadorian farmer who taught me that day how to climb a mountain.

Just as a caterpillar transforms itself into a butterfly, that day I was transformed into a different person by eliminating my self-doubts and overcoming my own personal adversity.