The Monarch butterfly and the milkweed go hand in hand.
Here is a short, but very interesting page about the Monarch butterfly and milkweeds. [link]
....an exert from the page... "The butterfly lays its eggs on milkweed plants. The growing larvae (caterpillars) eat milkweed leaves. These leaves contain toxins- poisonous chemicals. These toxins don't hurt the caterpillar, but they do make the caterpillar poisonous to most predators. Because it eats milkweed leaves as a caterpillar, the monarch butterfly is also poisonous. The survival of the monarch butterfly depends on this self-defense system provided by the milkweed. "
My daughter and granddaughter collect milkweed and monarch caterpillars every summer. They have a an odd *hanging tent* in their kitchen, where they can watch the caterpillars eating, and then making their chrysalis. And many times they are fortunate to also see them turn into the butterfly, which they then let go outside! They have been doing this since Mei ( my granddaughter) was 2 years old, she is now going on 7. Next year they plan on *banding* the butterflies.
Milkweed is disappearing in many areas due to construction and just destroying the plant, because it is considered a *weed* here. I let these plants grow, then collected the seed and placed them in an area that will not be mowed. Hopefully they will grow next year!
As with everything in life, there is always a connection to something else so we should be careful how we take care of our planet....after all, we are only the *caretakers* we don't own it.