from the National Wildlife Association
About ten years ago, a neighborhood friend of mine told me with great enthusiasm about her adventures raising monarch butterflies. I was intrigued. I followed her lead and went to a small plant nursery that didn’t use pesticides and bought my first milkweeds. Sure enough, I quickly encountered caterpillars! Unlike my friend, I did not bring the caterpillars inside to raise. Instead, I left them to survive in the confines of my backyard. As the first caterpillars grew and turned into eating machines, it was quickly evident; I needed more milkweed! Soon I was up to 50+ plants. That number would increase every year, as the number of hungry caterpillars increased to approximately 80 at a time!
Around year three, I noticed a disturbing trend among the newly hatched monarchs. Many were unhealthy, deformed, weak, and unable to fly. What was happening!?! I was distressed to see these sick and dying monarchs, and I wanted to know if I had done something that contributed to this unhealthy population. I started doing research, and my distress grew as I read about OE (Ophryocystis elektroscirrha), a debilitating protozoan parasite that infects monarchs. What I learned next stopped me in my tracks: one of the main reasons OE spreads in coastal areas is the predominant use of tropical milkweed, a non-native plant species that doesn’t naturally die back in the winter. Tropical milkweed (Asclepias curassavica) can also interfere with monarch migration and reproduction. What?!? But this plant is so easy to grow and maintain for a non-plant person like me! What are my alternatives? And what can I do with the plants I currently have?
Natural History Wanderings 
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