Tuesday, June 22, 2010

The Little Bog of Horrors

Note: This blog entry is bound to be controversial since it has to do with the introduction of non-native species, their spread, and what ought to be done about them.  I'll not take sides in the controversy but will let those who read this entry decide for themselves where they stand.

In early October of last year I went on a field trip with a small group from the Washington Native Plant Society.  I had seen the trip advertised on their website and had asked if I could accompany them, even though I was not a member of the WNPS.  They very kindly invited me along.

The field trip was advertised under the same name as this blog entry, "Little Bog of Horrors," and promised a visit to a floating bog where non-native carnivorous plants had been introduced and were flourishing (non-native, that is, to the state of Washington).

The field trip took place on a Saturday and took us to a small lake about an hour south of our home where we found five species of carnivorous plants growing.  We looked for a sixth, the Cobra Lily (Darlingtonia californica) but did not find it.

The trip was everything it promised to be and more.  After finding a place to park near the lake we made our way to the edge of the floating bog that almost completely surrounds the lake and balancing precariously on half-sunken logs and a few floating planks, made our way out onto the floating mat of vegetation.

I had never seen a floating bog before and it was amazing to see that this floating mat easily supported our weight and allowed us to explore right up to the edges of the mat.  One did have to be careful for holes and places the mat did not reach, and most of us, even those with high boots, ended up with wet feet.

We found a lot of different plants growing on the mat, including many sedges, the Western Bog Laurel (Kalmia microphylla),which was in bloom, and the Bog Cranberry (Vaccinium oxycoccos), whose fruits were just ripening.  In fact, I ate enough of the cranberries in the course of the day to give myself a stomach ache.

We explored the east side of the lake first and found three species of carnivorous plants there,and then followed the mat around the south end of the lake to the west side where we found two more species.  Later on we explored the northern end of the lake from a different route, looking for the Cobra Lily, but did not find it.

The first of the carnivorous plants we found was the Purple Pitcher Plant, Sarracenia purpurea.  This plant was growing in huge clumps, some of them several feet across and had already finished blooming.  We found this species only on the east side of the lake.

On the same side of the lake we found a number of clumps of the Yellow Pitcher Plant, Sarracenia flava,and these were in bloom, their strange flowers standing among the pitchers.  We could see large clumps of these on the other side of the lake as well.

This plant varied a great deal in color, from a bright yellow to a dull brown.  In some cases the pitchers had fallen over but in most cases they were standing tall, the largest being nearly three feet in height.

My son, who was along, had a small point and shoot camera and was able to take some pictures of the insects that were floating in the pitchers.  One of his photos has since been published in the March-April issue of the Mexican conservation journal, Especies, in an article on carnivorous plants.

Also on the east side we found the Roundleaf Sundew (Drosera rotundifolia).  These tiny plants were everywhere, but were hard to see because they are so small.  This is actually a native species, but may have been introduced in this location.  One had to get wet to get down far enough to take pictures of these delightful plants.

Making our way around the south end of the lake we continued to see clumps of the Yellow Pitcher Plant, and on the southwest end of the lake found it everywhere, growing, like the Purple Pitcher Plant, in large clumps.

On that same end of the lake we found two new species, one of which was the well-known Venus Flytrap (Dionaea muscipula).  These, too, had finished blooming sometime before, but many of the traps had insects in them.  They were not as abundant as the Pitcher Plants, but the clumps we found were very large, some of them with hundreds of traps.

Nearby we found several individual pitchers of the White Pitcher Plant, Sarracenia leucophylla.  There were not more than half a dozen of these and they seemed less securely established than the other species of Sarracenia.  They also varied considerably in color, the deep maroon veining being much heavier on some plants than on others.

No one seems to know who introduced these species and why.  No one even seems to be sure how long they've been there.  Nor, it seems, does anyone quite know what to do about them.  Apparently the DNR has discussed the possibility of trying to eradicate them, though I think this would probably be quite difficult in the case of Yellow and Purple Pitcher Plants, which are very well established.

Since then my son and I have made several trips back for photographs and in the hope that we would find some of the other species in bloom.  We hope to go again later this summer when the Venus Flytrap and the Purple Pitcher Plant are blooming, but the last trip we made this spring found the water in the lake very high and made the effort to get out on the floating mat a real balancing act.


  1. First of all, thank you as always for the lovely photos.

    It is hard to know what to think. On one hand the ecology of these plants is interesting and exciting to see first hand.

    On the other hand they are abnormal predators, for lack of a better term, and are out of place. They impact the ecology of this pond.

    Are they displacing a native plant. Are they robbing the prey from native animals or plants that would use them. If they were pulled what would move in.

    If they were threatening escape I would want them to get aggressive, but if they are confined to this environment there is a tip in their favor.

    The pond and bog sound unique, however. From that standpoint I would hope they do what they can to preserve and protect a fragile place

    No one answer. Pulling/ controlling invasives can be done but it can take years of replication , year round , to get a success

  2. The good thing about this place, Marti, is that the Lake is very isolated with no evidence that these plants are spreading elsewhere, and they do not seem to have had a huge impact on the ecology of the place, though of course, that is not always so easy to tell.

  3. yes I will always have a concern when it comes to the environment and frogs and toads. But then again, some of these plants can support a tadpole.

  4. Interesting post. I lived in Olympia for a time and had no idea these introduced plants were up there. As far as I know, only a handful of carnivorous plant species have ever shown any tendency toward invasiveness or altering their environment significantly. Utricularia inflata, for example, is invasive in several lakes in Washington State, New York, and elsewhere in New England; it has been shown to dramatically alter the water quality and become quite weedy. Most of the other carnivorous plant species, though, are quite reserved and require such unique growing conditions that invasiveness is out of the question.

  5. Thanks for the comments, Ryan. It's good to know that there's nothing to worry about with therse plants. We were down there again yesterday - took a friend there, so I'll be doing yet another post about the place in the next few days.

  6. I like the concept of a "quite reserved" plant, but you are right, "aggressive invasive" is the opposite term.

    I visited the bog with Ron and it is a wondrous and unique place

  7. Tanks for commenting Marti and grice.


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