On July 21 the monarch butterfly was declared endangered by IUCN (The International Union for the Conservation of Nature). Being listed on the IUCN Red List means it is the first time the monarch has been officially considered in danger of extinction.  Evidently, there is a big difference in which population —the eastern or the western— is more at risk.  Our western population has declined 99.9 percent in the last few decades, from around 10 million in the 1980s to under 2,000 in 2121.  The eastern population declined by 84 percent between 1996 and 2014.  There was a recent controversial study based on citizen-science data from summer nesting sites that showed an increase in some US locations.  However, according to the latest research, it is the winter data that tells the real story.  Even if populations rebound in some places in the summer, overwintering populations, whether declining or even remaining stable, are just way too low.  

So what to do?  As always, plant as much milkweed as possible, because chemically sprayed  farmland milkweed, loss of habitat, and overdevelopment of traditional nesting grounds are some of the reasons our gardens seem to be the last ditch resource for our western monarchs.   We advocate planting native milkweeds, but if you do plant tropical milkweed, be sure to cut it back in the fall/winter.  Tropical milkweed stays green and discourages monarchs from migrating. Cutting it back also helps to eliminate spores that could be on the plant. Climate change has made it easier for tropical milkweed to overwinter in our area.  So I repeat, be sure to cut it back.  Look for native milkweed plants at our CNPS plant sale this fall.  We’ll keep you updated on which species will be available.  

Monarch Update