Friday, June 5, 2015

Milkweed Chronicles - Asclepias Syriaca, Common Milkweed

When I was nine or ten years old, National Geographic magazine featured a cover story heralding the discovery of the migrating monarch butterflies' legendary overwintering site in Mexico. I can still remember my feelings of awe and envy as I considered the young lady on the cover smiling serenely in the embrace of millions of magnificent monarchs... 
How wonderful it would be to become an explorer like her, and someday commune with such an awesome congregation of wild creatures!

From that day forward, the migrating monarchs became a significant marker of my years growing up wild in North Carolina, as I eagerly surveyed the late summer skies each year for monarchs passing through the Sandhills on their way south. My experience was far from unique, and Americans' fascination with the monarch almost certainly places it among the most widely recognized wild animals in North America. 

Much to the dismay of their millions of fans across North America, hibernating monarch numbers have crashed drastically in recent years, declining by perhaps as much as 90 percent after numbering nearly a billion individuals in the mid-1990's.  
While a variety of factors have likely contributed to this dramatic decline, habitat loss in the monarch summer breeding range and associated reductions in the availability of milkweed plants, the exclusive food source for monarch caterpillars, are both factors which hit pretty close to home .

Various conservation organizations are joining in unprecedented cooperation with the governments of the United States, Mexico and Canada to better understand the crisis and help save this imperiled butterfly species which we so recently took for granted as a component of natural landscapes across North America. 
One important focus of these efforts is to restore the milkweed populations which have been decimated by herbicides and vanishing habitat.

In support of these efforts, Hoot Owl Karma is highlighting the native milkweeds of our area to kick off the summer wildflower season. 
Featured in the first of four posts is the Common Milkweed, Asclepias syriaca. 

True to its common name, Asclepias syriaca is still rather common throughout our region, thriving on roadsides, sunny wood margins and old fields, sometimes forming imposing stands of a dozen or more plants, like this clump along the Deep River near Carbonton in Lee County.

As you can see from our photos, milkweed is a source of abundant nectar and pollen for a wide variety of arthropods, including bees, butterflies and beetles in various stages of development, transforming even a brief visit to the milkweed patch into a veritable entomology lab .

The plants in this particular colony stand from four to six feet tall, and they are covered with sturdy, lush green leaves, the preferred food of the monarch caterpillar. 

Milkweed's name derives from the milky white latex that fills the stems and leaves. This substance contains a chemical which is toxic to most animals, including humans, but the monarch caterpillar is unaffected. In fact, the chemical provides larger caterpillars and adult butterflies with significant protection from predators.

While the milkweed in our photos is of the wild native variety, common milkweed and several other native species are quite easy to propogate, and there is evidence that planting even relatively small oases of milkweed can be helpful to breeding and migrating monarchs.  

 So whether you have an interest in the plight of the monarch or simply admire the beauty of our native milkweeds, we encourage you to browse the abundant resources available online, and see if there's a place for you in this important conservation effort.

Our nectaring monarch has moved on for the moment, but this pipevine swallowtail drifts in for a sip, while a troop of orange and black soldier beetles, or Pennsylvania leatherwings, scour the blossoms for pollen and nectar...
an entire ecosystem in minature, 
our little patch of common milkweed,

and so goes this chapter of the Milkweed Chronicles,
along a quiet country roadside near the Deep River bridge.

We'll resume the story a little later down by the creek with the purple milkweed and the bumblebees; hope you can join us! 

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