Milkweed has come back!

Milkweed is one of California native plants. This spring milkweed plants returned in my backyard exactly at the same location (Fig.1), suggesting they are perennials. Milkweed plants are very important because they are the only food for precious migrating butterfly, Monarch butterfly (please read an artible in National Geographic). For most organisms milkweed is toxic because their body contain several glucosidic substances called cardenolides. Why the glucosidic substances are not toxic to Monahch butterfly? That is an interesting question.

The number of Monarch butterfly have been decreased due to multiple reaspons reported in Scinece magazine. Reduction of native milkweed plants is thought to be a big cause. To support efforts to restore vegetation for Monarch butterfly by many organizations such as Xerces.org, I planted milkweed seedlings 2013.

We need to be careful which milkweed species to plants because some non native tropical species contain a protozoan parasite called Ophryocystis elektroscirrha (OE) that cause diseases in Monarch butterfly (https://www.sciencemag.org/news/2015/01/plan-save-monarch-butterflies-backfires). The National Wildlife Federation looks provide information of native milkweed at your location.

Save native plant vegetation!