Thursday, November 5, 2009

Finding Frostweed

November 4, 2009
Mud Pond, Moreau Lake State Park

With the coming of colder weather, it’s time for an annual ritual – finding Frostweed.
It was three years ago that I first saw it. That was when I went on my first-ever guided hike in Moreau Park. It was a little morning tour around Mud Pond, led by then-park-naturalist Laura Connor. Neither she nor I knew what in the world it was when we saw it.
Later at home, I looked it up in Henry Thoreau’s Journal (which I had just checked out of the local library for the umpteenth time) – and found therein a perfect description of it, including his little field-sketches.
At that moment, Thoreau, Moreau and I were bonded – and we’ve been inseparable since !

There is more than one plant known as Frostweed, but the variety we see in upstate New York is Helianthemum canadense, or Rockrose, a small plant in the Cistus family. It puts forth a delicate, primrose-yellow blossom in early June ( and again in late summer, something the Journal entry clued me in on.)

When the first frosts come, the seemingly lifeless embrowned plant forms curls of frost along the stem. Apparently the stem splits from the cold, and there is enough sap remaining to form vapors -- which then freeze, looking like extruded cotton candy by morning.

It’s an ephemeral phenomenon, since it happens only a few times per plant, and since the sun’s first weak rays are enough to melt these formations. You’ve got to get up early to see it!

Which is what I did today, arranging to meet with park educator Dave at 8 am at Mud Pond. He had a group of kids coming in to the Nature Center at 9:30, so we drove to the far end of Mud Pond for a quick Frostweed-Finding mission.
We found it within ten minutes. (By now I know where the plants are.)

Along the way, the frost had settled on the upper surfaces and edges of most everything.

I saw a mushroom that had escaped the night's descending frost by hiding:

But the frostweed frost is different – it comes from within:

You can see how the stem splits:

Here is the plant in June, and how it appears now (sans frostworks). It favors sandy soil.

So now, you can look around and find your own patch of this remarkable plant. But get out there soon!
By the end of the month, it will look like just another dry stem in a tangle of brown twigs.

There was just a little time left before Dave had to head back to the Nature Center, so we walked just as far as the hillside above the beaver lodge.
After a banner year for deer-ticks, during which all of my Moreauvian friends have had close-encounters of the unpleasant kind with them, the sightings seem to have greatly declined.
I shared with Dave my astute observation that
“I haven’t seen a single deer-tick since August!”
“Like this one?” he replied, casually plucking a very-much-alive tick from the leg of his wool pants.

It is striking how much change has occurred since that colorful day a mere week ago. Most of the bright leaves are down, but the water is still a beautiful looking-glass.
At this time of morning, the geese have not yet arrived.
It was serenely quiet. And then --

I heard an odd noise, and turned to look. Was that Dave’s stomach growling?
Then he heard it too. A sort of froggy, purring noise.

We saw a small group of hooded mergansers in the next cove. The males were pursuing each other, even coming straight at each other in little watery jousts.

All the while they emitted that growly noise. You can hear it at

We took photos of frost, fungi and the hoodies, testing the limits of our cameras’ macro and zoom lenses.

After just a few moments, the mergansers got wise to our presence. They postponed their arguments and beelined for the other shore, silently.

Then, as if to prove that Nature abhors a vacuum –- came a distant honk from the first arriving goose of the day.
My watch bleated out a weary beeep beeep beeep – - nine a.m.
Time to head back.

Oh and here is a copy of the Journal page, which three years ago, set me on this Trail which I now so happily tread.
(the photo is my own, from that day three years ago.)


  1. This post is terrific, Sue. Thanks for copying those pages from Thoreau's journal. I can't wait to join you on our hunt for Frostweed and whatever other wonders await at Moreau Lake State Park. What a treasure we have in that wonderful park!

  2. These are lovely pictures - and what a fascinating find! I feel curious as to whether there are any plants native to the UK which also exude frost; it seems to me that something must. It will probably be a while before it's cold enough to find out in London and some years we get no frost at all. But when I'm out of town I'm going to go searching for this on a frosty morning - and you've given me the clue so if I ever find it by accident, I'll already know what caused it.

  3. Very interesting -- that's a new one for me! Some nice shots (!) and a nice read.