# Milkweed and monarchs, for kids Written for somebody about eight to twelve reading it themselves. ## Ten things that sound made up ### A monarch tastes with its feet A female monarch drums on a leaf with her front legs before she lays. Sensors on her feet taste the surface, and if it is not milkweed she moves on. She can tell one species of milkweed from another this way. ### The butterfly that flies to Mexico has never been there It takes three or four generations to get north over the summer. The one that flies all the way back to Mexico in the fall is the great-grandchild of the one that left. Nobody has shown it the way, and it goes to the same few acres of forest anyway. ### A caterpillar grows two thousand times heavier in about two weeks It hatches smaller than a grain of rice and ends up the size of your little finger. If a human baby did that it would weigh as much as a small whale by the end of the month. ### A caterpillar cuts the leaf before it eats it Milkweed sap is under pressure and sticky enough to glue a caterpillar’s mouth shut. So a monarch caterpillar bites a little trench across the leaf first, lets the sap bleed out, then eats the part beyond the cut. It works this out with no one teaching it. ### Monarchs are poisonous, and they want you to know Milkweed contains cardenolides, which stop a heart working properly. Monarchs eat them anyway, store them in their own bodies, and stay poisonous for life. Orange and black is a warning sign, not camouflage. ### A bird only has to be sick once A blue jay that eats a monarch throws up, and never tries an orange-and-black butterfly again. That is the whole point of being brightly colored. It costs one butterfly to protect all the others. ### The chrysalis has real gold on it Well, gold-colored. A monarch chrysalis is jade green with a line of dots that shine like metal. They are not pigment at all; they are layers that bend light, in the same way a soap bubble does. ### Milkweed flowers are booby-trapped Milkweed does not sprinkle loose pollen like most flowers. It packs it into two waxy bags joined by a wire, and a visiting insect has to catch a leg in a slot and pull them out. Small insects sometimes get stuck and cannot escape. ### One pod can hold two hundred seeds Each seed has its own parachute of silky floss. During the Second World War, when a material called kapok ran out, American schoolchildren collected milkweed pods by the sackful to stuff life jackets. It floats, and it does not soak up water. ### Almost everything on a milkweed is orange and black Monarchs, milkweed bugs, milkweed beetles, tussock moth caterpillars, the aphids. None of them are closely related. They all eat the same poisonous plant, and they have all separately arrived at the same warning colors, because a predator that learns one of them has learned them all. ## Six things to go and do ### Find a milkweed and prove it Time: An afternoon. You need: Eyes. A notebook if you like. Milkweeds give themselves away three ways, and you can check all three without picking anything. 1. Find the flowers. Every stalk in the cluster comes out of one single point, like the ribs of an umbrella. Each flower has five petals bent backward and five little cups standing up above them. 2. Look at how the leaves sit. Most milkweeds have them in facing pairs. Some have them one at a time, and a few have three or more in a ring around the stem. 3. Check the sap, carefully. Snap off the very tip of one leaf and watch the break. Nearly every milkweed bleeds thick white sap within seconds. Wash your hands afterwards and keep it away from your eyes. Then what? Once you are sure it is a milkweed, work out which one using the key on this site. ### Watch one flower head for ten minutes Time: Ten minutes. You need: A watch, and somewhere to sit. This sounds boring and is not. A milkweed in flower is one of the busiest places in the whole meadow, and ten minutes is long enough for the traffic to sort itself out. 1. Pick one cluster of flowers and sit close enough to see it properly. 2. Every time something lands, make a mark. Bees in one column, wasps in another, flies, butterflies, beetles, anything else. 3. Watch the legs of the big ones. If you are lucky you will see a bee fly off with the milkweed’s pollen bags clipped to its foot, like tiny saddlebags. 4. Look underneath the leaves and inside the flower head too. Crab spiders sit in flowers with their front legs open, waiting. Then what? Do it again at a different time of day. Milkweed smells strongest in the evening, and a different crowd turns up. ### Trick a seed into thinking winter has happened Time: A month of waiting, then twenty minutes. You need: Milkweed seed, a damp paper towel, a plastic bag, a fridge, pots and compost. Most milkweed seed will not grow until it has been cold and damp for about a month. That is the plant making sure it does not sprout in October and freeze. You can fake the winter in a fridge. 1. Dampen a paper towel, wring it out so it is not dripping, and fold the seeds inside it. 2. Put the towel in a plastic bag, label it with the date, and leave it at the back of the fridge for thirty days. 3. Sow the seed in damp compost about as deep as the seed is wide. That is barely covered. Milkweed seed needs to feel light. 4. Keep it warm and damp. Most species come up in one to two weeks. 5. Try a fair test: keep back half the seed, do not chill it, and sow both lots on the same day. Count how many come up in each. Then what? Plant them out where they will get plenty of sun, and leave them alone. Milkweed spends its first year building roots and can look disappointing above ground. ### Tell a monarch from the ones pretending to be one Time: Twenty minutes. You need: A photograph, or a butterfly holding still. Three orange-and-black butterflies get called monarchs, and only one is. Learning the difference takes about a minute and is very satisfying. 1. Count the black lines. A viceroy has an extra black line curving across the back wing that a monarch does not have. That one line is the whole trick. 2. Check the size. A viceroy is noticeably smaller, and it flies in a flappier, less gliding way. 3. Look for a plain brown one. That is probably a queen: same family, no heavy black veins on top, white spots scattered over the front wing. 4. Count the caterpillar’s tentacles. A monarch caterpillar has two pairs of black filaments, a queen caterpillar has three. Then what? The viceroy is not simply copying. It turns out to taste unpleasant in its own right, from the willow leaves its caterpillars eat. Both butterflies are genuinely nasty, and both benefit from looking alike. ### Count something, and send it to a scientist Time: Half an hour, once a week. You need: A milkweed patch you can get to. Nobody can watch every milkweed in the country. Real monarch research depends on ordinary people counting what is in front of them, which means your numbers can end up in an actual study. 1. Choose a patch of milkweed you can visit regularly. Ten plants is plenty. 2. Each week, check the same plants. Count eggs, count caterpillars, and write down the date even when the answer is none. Zero is data. 3. Look under the leaves. A monarch egg is a pale, ribbed dot smaller than a pinhead and is almost always on the underside. 4. Send your counts to a monitoring project. Journey North and the Monarch Larva Monitoring Project both take records from anyone. Then what? Weeks when you find nothing matter as much as the exciting ones. A record of absence is what lets anybody prove something changed. ### Turn a patch of ground into a monarch stop Time: A weekend, then years. You need: A sunny patch, milkweed, some late-flowering plants, and permission. A migrating monarch needs two things: milkweed to lay eggs on, and flowers to drink from on the way. A surprisingly small patch is enough to be worth stopping at. 1. Find out which milkweeds actually belong where you live. Planting the wrong one is worse than planting none. 2. Put in at least ten stems in a group rather than scattering them about. A female monarch finds a clump far more easily than she finds one plant. 3. Add flowers that bloom late. In September a migrating monarch needs fuel more than it needs a host plant, so goldenrod and asters matter enormously. 4. Leave the dead stems standing over winter and cut them in spring. Birds take the fiber for nests and insects sleep inside the stems. 5. Do not spray anything. Ever. Almost every spray that kills a greenfly also kills a caterpillar. Then what? You can have a garden officially registered as a Monarch Waystation, and get a sign for it. ## Questions people actually ask ### Can I keep a caterpillar? You can watch one, and the very best place to watch it is on the plant where it hatched. Raising monarchs indoors is popular but it is not as helpful as it looks: crowded containers spread a parasite called OE between caterpillars, and butterflies raised indoors have been found to navigate worse than wild ones. If you want to help, plant milkweed and leave the caterpillars on it. ### Is milkweed poisonous to me? Do not eat it, and keep the sap out of your eyes. Milkweed sap is bitter and irritating, and it can hurt a lot if you rub your eye after touching it. Handling the plant is fine. Wash your hands afterwards, the same as you would after gardening. ### Why did my caterpillar disappear? Most likely something ate it. Out of hundreds of eggs a female lays, only a handful reach adulthood: wasps, ants, spiders, stink bugs and birds take the rest. It is grim, and it is also why she lays so many. A caterpillar that vanishes when it is very large may instead have walked off to find somewhere to pupate, sometimes several meters away. ### How long does a monarch live? About four or five weeks for most of them. But the generation that hatches in late summer is different: it does not breed straight away, it flies to Mexico, and it lives for around eight months. Nobody fully understands how the same species does both. ### Do monarchs sleep? Not the way you do, but they do settle at night and go still, usually under a leaf, and they cannot fly until the sun warms them up again. On migration they roost in groups, sometimes thousands together in one tree. ### Can I help if I do not have a garden? Yes. Count things and send the numbers in, which is real science and needs no land at all. Ask whoever manages a park, a school field or a churchyard about planting milkweed there. Or grow one plant in a big pot; even a single flowering milkweed is a refueling stop. --- Source: https://milkweedusa.com/kids/ — Milkweed USA, CC BY 4.0.