- Issue: Summer 2015
Every fall, millions of monarch butterflies travel thousands of miles across North America to hibernate in the forested mountains of central Mexico. But the number of boldly patterned lepidopterans wintering in Mexican forests has plunged to one of the lowest levels since monitoring began more than 20 years ago.
One of the main threats to monarchs is the eradication of milkweed plants along their migratory route. Milkweed is the primary food source for the insect—and the only plant where the females lay their eggs. But in the US, vast quantities of milkweed have been wiped out by herbicides, agricultural expansion and urbanization. In some states it is estimated that 90% of all milkweed has disappeared.
While the decline of the monarch butterfly is alarming, one of the remedies is simple. We need to increase native, pollinator-friendly species of milkweed throughout the US and Canada. And you can help.
Plant native milkweed in your garden—or even on your balcony. Ask your local nursery or a nearby gardening group about the right type to plant in your growing region (tropical milkweed, the most widely available variety, is not the best for monarchs). By planting a pollinator garden, you will give migratory monarchs a much-needed respite from the dangerously sparse food supply on their long journeys north and south.
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