The Monarch butterfly

Milkweed and monarchs: a symbiosis

The various native milkweed species (syriaca, incarnata, tuberosa, exaltata) and the monarch butterfly (Danaus plexippus) form a symbiotic relationship together. All parts of the plant contain a sticky white latex, which is toxic to most animals except the monarch butterfly. The caterpillars feed exclusively on the leaves of this plant, including the sap. Both the caterpillar and the adult butterfly retain the toxic properties of the sap, which protects them from predators. In exchange for this gift, the butterfly pollinates the milkweed and allows it to reproduce in turn. Currently under threat, the monarch has a bright future ahead if milkweed begins to be cultivated on a larger scale. Right now, monarchs can have a hard time to reproduce with only the small milkweed patches they can find in urban wasteland, roadsides or private gardens. They either can't find them, or the patches will be too small to sustain large migratory groups.

Large milkweed plantations would really be a salvation for this species, creating gigantic habitats allowing it to thrive, whereas before, milkweed was viewed as an undesirable weed and systematically eliminated to make room for other crops.

Milkweed patch in downtown Quebec City, Canada.
Milkweed patch in downtown Quebec City, Canada.

Milkweed plantations, a lifeline for monarchs?

Milkweed fields are somewhat reversing the trend that has been observed for decades in North America: systematically eliminating this plant, which is considered harmful in rural areas either because of its toxicity to livestock or because it can easily invade the fallow fields, being a perfectly adapted native plant. This new paradigm is a glimmer of hope for the endangered species that is the monarch. Indeed, available research and statistics suggest that the monarch population increased dramatically at their usual wintering sites in Michoacan, Mexico, from 2014 to 2019. And the large-scale cultivation of milkweed just started in Quebec and Vermont in ... 2013!

Evolution of area occupied by monarch butterflies from 1994 to 2019.
Evolution of area occupied by monarchs - 1994 to 2019.


It would therefore seem that the root cause for the decline of the monarch populations over the last few decades is the deterioration of the monarch's breeding grounds (lack of milkweed in sufficient amounts, ideally in rural areas), whereas before, other factors like pesticide use and climate change were viewed as the main culprits. This conclusion, although somewhat speculative, seems to be confirmed by a study carried out at the University of Guelph, published in the Journal of Animal Ecology. And precisely this year (2020), the population of monarchs has fallen dramatically again. Precisely the year several farmers gave up milkweed after 6 years of roller coasters, because of a lack of business opportunities.

In summary: Milkweed abundance is essential for the survival of monarchs, but this abundance is almost impossible to achieve if it is not cultivated at a larger scale for its commercial potential. One of the main reasons we started Lasclay is to address this urgency: We seek to bring this promising material forward, to demonstrate that we can create a better future with the vast possibilities given by the humble milkweed.

It is very rare that the exploitation of a raw material is a net benefit for the ecosystem during its entire lifecycle, even if it is natural. Just think of down or cotton, which are respectively a major source of animal cruelty or environmental devastation ... or both. Not to mention synthetic petroleum-based insulation!

Milkweed seems to belong to that rare category of natural, complex, ethical raw materials whose exploitation supports the balance of its ecosystem and the survival of the species that depend on it. This is what appeals to us the most.