Naturalist Notes
July 2017
Our Butterfly weed (Asclepias tuberosa) has caused an explosion of color in the park this month. While much of it is bright orange in color, there are some variations from prairie to prairie, and plant to plant. In our demo gardens on the north end of the park, you can observe some that are more of a reddish hue, and some that are a lighter orange (a bit more yellow). These plants are loved by many of our pollinator species, such as the western honey bee (Apis mellifera) in the picture to the right. The orange coloration also attracts monarch butterflies (Danaus plexippus) who utilize their stiff foliage as they move from caterpillar to chrysalis form.
While monarchs may transform on butterfly weed, they exclusively eat common milkweed (Asclepias syriaca) and other milkweed species in their caterpillar stage. Similar to other insects that feed on milkweed, their diet gives them an unpleasant taste that deters predators. Decreases in common milkweed populations, as well as disease and predation, are directly linked to decreases in monarch populations. In 1996, it was estimated that over 1 billion monarchs resided in the US (during summer months), which had decreased to 35 million in 2013. We will be maintaining a few areas of milkweed to help address this issue here in the park.
Look closely at the milkweed throughout the park and see if you can find these other insects that call milkweed a home:
Lakeshore State Park
Wisconsin Department of Natural Resources