23 May 2010

The Monarchs have arrived in Wisconsin

Yesterday I captured this image of a female ovipositing on a newly-sprouted milkweed.  When you see a butterfly visiting a non-flowering plant, it's obviously not nectaring.  It may be basking in the sun to recharge its solar batteries, or, as in this case, depositing eggs.  Monarchs curl the abdomen down briefly to just touch the plant and place a single egg.

The white egg itself (click photo to enlarge) is actually sort of camouflaged because it looks like a droplet of milkweed sap exuding
from the plant.  And since the sap is relatively toxic to most insects, it probably looks less attractive.

These photos were taken at the edge of a field which a farmer is in the process of enlarging to accommodate a larger corn harvest.  Unfortunately, he has extended it into a patch of milkweed that has been growing there for a long time (it takes several years for a milkweed to build up a root system sufficient to support a flowering several-foot-tall plant).
He tilled the field a couple weeks ago.  The milkweed are sprouting right on schedule, but they are doomed because he will be back to plant the corn quite soon.  The milkweed will get disced under at that time and likely not resprout.  This is sadly representative of what is going on around North America, as traditional Monarch (and other butterfly) habitat is lost to agriculture (and homebuilding).  I would encourage those of you who are interested (and blessed with a yard/garden) to consider growing plants that support butterflies either as food for their caterpillars or as flowers for their nectar. 

4 comments:

  1. On our farm we have a fair bit of milkweed (in local parlance also known as cotton bush, wild cotton or swan plant). It's not native to this area and is considered a noxious weed. So it's a bit of a dilemma, really: I know the butterflies depend on it for their lifecycle, but on the other hand it's poisonous (too bitter for the horses to eat though: they know better)... but it competes with native grasses and plants. So at present I keep two and a half paddocks (= fields, each about 2 - 4 acres) free of the plant by pulling it out by hand (strangely, unless I wear gloves, a few hours after working on this job my tongue and lips go numb for a few hours ... must be the toxicity). The rest of the farm (the lower paddocks) though have plenty of milkweed and we have lots of wanderer butterflies as a result.
    I'm just not sure what constitutes best practice is in this regard, though ... I guess in the best interests of the natural, native environment I should pull it all out ... But I'd miss the butterflies!

    ReplyDelete
  2. P.S., If you look at this link you can see one of our horses standing in a patch of young milkweed down in the lower paddock:
    http://moretons-myth.blogspot.com/2010/05/novas-back.html

    (I know, I know, you can spot a host of other invasive weeds there too: lantana, camphor laurel, scots thistle ... ::sigh:: ... I'll get onto them, I will ...)

    ReplyDelete
  3. In the children's garden we just built for our summer nature camp, we made sure to include plenty of butterfly-attracting plants: fennel (for swallowtail caterpillars), butterfly bush, cosmos, cabbage (for cabbage butterflies), moonflower (for moths in the Saturniidae family), and tons of other fragrant, colorful flowers. Our park has tons of milkweed, which the kids learn to identify easily on our nature hikes. Can't wait 'til the kids and the butterflies are sharing the garden! And we'll be on the lookout for monarch eggs and caterpillars on the milkweed!

    ReplyDelete
  4. Dr.Mieke, lantanas and especially thistles are host to a variety of butterfly caterpillars, but you may need to weed them for the sake of your horses.

    ReplyDelete