At first it seemed like a restoration attempt that failed. Then, for a while, this partly parasitic beauty just barely hung on. Gradually, we learned to nurture a species that had good reason to be called "wild and crazy."
The eared false foxglove (Tomanthera auriculata) is threatened in Illinois and under review by the U.S. Fish and Wildlife
Service for the federal endangered list.
Eared false foxglove – first
confirmed near the North Branch by a student of H.S.Pepoon,
who probably traveled to its habitat on the “Crazy Train.” |
According to the “National
Collection Plant Profile” of the Center for Plant Conservation, this species
has “About 40-50 known occurrences, most with populations of only 25-250
individuals.” The largest populations are found in Arkansas, Mississippi, and Missouri.
Recently discovered in Kentucky. Presumed extirpated in Michigan, New Jersey
and Texas.
The species was already
rare here in 1927 when H.S.Pepoon published the Flora of the Chicago Region. But
one of the three occurrences he listed was a few miles south of Somme at
“Dunning” – then a relatively wild and unsettled area. Most people didn’t want
to live there, perhaps because it was the location of Chicago’s insane asylum. The
main transportation to Dunning was called the “Crazy Train.” This false foxglove
may actually be a bit unbalanced itself; the species seems not to do well in
settled situations; the little rascal seems to need violent disturbance.
Methods
As we searched for seeds to restore health to depleted ecosystems, we noticed this foxglove
in small numbers at three sites in Cook County; at each it seemed to be associated
with areas where shrubs had recently been burned back by fire. Fluctuating
shrub borders were once a major feature of the tallgrass landscape. Shade from
shrubs can kill prairies. When we started with Tomanthera, most prairie
managers were trying to wipe out shrubs completely.
We wondered if this
species might have a role in the savanna dynamic (Packard 1988). We collected
a few seed capsules from a few plants south of
Dunning. We broadcast that seed in areas of Somme Prairie Grove that seemed similar to where we
found it and had similar plant associates to those listed by Swink and
Wilhelm (1994). A few years later we heard from Ron Panzer that a large population
near Midlothian was about to be destroyed. Panzer provided us with about one
quart of seed capsules, and we broadcast that seed where a few of the Dunning
plants had bloomed – and similar areas.
Date
of the First Seeding
Oh, yes, it would be
great for this report if I could find recorded dates and details of those first plantings. I can’t, so far. I do
remember that they happened.
Tomanthera’s seeds are odd and fragile looking, yet they survive in the soil
and germinate after many years. What’s with the honeycomb
effect?
|
A
1988 reference in Natural Areas Notes suggests that I may have sowed
the seeds that early. I was collaborating then with Gary Horn, a fellow volunteer
steward and an animal keeper at Brookfield Zoo. He carefully managed a “south of Dunning” site. We had just started to burn that newly discovered
prairie, and the foxgloves popped up next to some burned shrubs. Gary has
sharp eyes, and he discovered that deer were eating all the foxgloves before
they could set seed. So he tried some recommended deterrents: he scattered
human hair near the plants (a failure) and then lion hair (also failed). He
finally succeeded with his ‘ultimate weapon’ – leopard dung. According to Gary, “Leopard dung has a smell beyond
imagining.” He reported that his rare plants then flowered and set seed.
The first foxglove entry
I can find in the Somme field journal comes ten years later:
“Sept.
4 (1998). Tomanthera auriculata appeared for the first time (although
I can easily believe it’s been there previously; it would have been easy not
to find it; especially since the flowers fall off by afternoon).”
For
five years, no subsequent mention of Tomanthera in my journal – but in 2003
there’s the note:
“August
24. Found Tomanthera auriculata for the first time in years. Also
first time in years that that area has burned. 31 plants along old footpath
to Circle Grove … scattered up to 10’ from the trail. Also found one plant
2/3 of the way to the Pothole Pond ... Both of these (areas) have now been
scythed.”
Here's the translation: An intense fire –
scorching a brushy area that hadn’t usually burned – results in thirty-one
foxglove plants. And why scything? A scythe is that long-bladed implement
that Father Time carries on New Year’s. We had noticed that saw-tooth
sunflower and tall goldenrod could become “thugs” – overpowering and eliminating most other vegetation, under some circumstances. In high-quality ecosystems, they’re not common but multiply
after disturbances, like a scab that helps heal a wound. In degraded
ecosystems, like we’re working to restore, they can get out of hand and
prevent healing. In previous experiments, scything these thugs back into
balance seemed to have long-term benefits for diversity generally – and
especially for some rare plants. Now we started to help out Tomanthera by scything thugs in areas
where it used to thrive. We later found that the foxglove sometimes returned
years after scything. One good thing about crazy annuals is that seed may lie
in the ground for years or decades, waiting for the right conditions.
In July 2004 eighteen Tomantheras bloomed. So far so good. But a note in my journal that fall
indicates that only one plant survived to make seed. That hurts. I remember a
foreboding: What’s wrong here? Is Tomanthera doomed – a few plants pop up
some years; then they’re gone, perhaps no new seed being made for the future.
Almost certainly I took half the seed from the one successful plant and scattered it in other likely places. I find no note to that effect, but that's what I would have done with so rare a plant.
In 2005, the data page
shows a whopping 75 plants bloomed. Did they survive to make seed? Did I
check? No note on that. Certainly I had good intentions - but lots of competing work and only so much time. My comments in 2006 suggest disaster – and a determination to do better.
August 27, 2006: a jumble of rushed words:
“Put
out 2 cages and 8 mouse traps for Central Swale population of Tomanthera.
(There had been 6 plants on the 25th. One of them cut off at
ground level on the 26th.) 28th: 1 short-tailed shrew.
29th: 1 each deer mouse and meadow vole.”
There my notes stop, but
my memory is vivid. Mouse traps? Short-tailed shrew? The battle has just kicked up a notch.
Here's the drama, as it unfolded: On August 25th
I had been excited to find six foxglove plants far from the area where I’d seen them in the past. (Probably I’d broadcast seed in all these areas back
when Panzer donated it. Probably the little crazy little devils sense chemical and
physical changes that indicate conditions may be right for them. Then they
germinate and bloom. If they can set seed, the population may continue. If
not, the population flickers out.) When I checked the next day, one of the
six had been cut and sectioned. Not only were the deer eating the foxgloves
from above; the meadow voles were attacking from below.
Voles are clever. They
stay in grass tunnels but drag lofty seedheads down to them. A vole stands up
and gnaws through the stem, grabs the new bottom, pulls it down to the
ground, stands up, makes another cut, and keeps repeating that sequence until
it has a pile of vole-length stems on the ground and the seed capsules down
where it can eat them in safety. Hawks eat voles that are not hidden in the
tunnels they make through the grass.
So on the 27th
I probably pirated a couple of deer protection cages from some lesser priority species and put out 8 humane
Havahart live traps baited with oats, peanut butter and molasses.
Next day, despite my
efforts, another stem was vole-cut. Four left. If we could only protect just
a few long enough for next year’s seed. I had a dozen snap traps to fight off
the mice that otherwise devastated the rare seed we gathered and stored for
later planting. But killing the little gerbil-ish rodents in the wild (even
with FPD approval) felt different and more ugly. All the same, losing an
endangered species population felt worse. However, no voles blundered into
the snap traps despite delicious bait. One shrew was in one trap. Next day,
another foxglove was gone.
On the 29th,
one vole and one mouse died in traps. But others had avoided Havahart
and snap traps to get another
Tomanthera. The assortment of contraptions looked insane amidst the nature.
Next day, another
foxglove down. Now just two left. I have other things to do in life. I don’t
have time for this. But I go to the hardware store and get talked into a
package of stinky stuff – blue cakes of foul stench – guaranteed to repel
voles. I place four of them around those two vulnerable stems.
Next morning I return,
wracked by angst. Yet the scene I see makes me laugh out loud. It’s an oddly
free and happy laugh – a laugh of the absurd. I stare down at a little piece
of wilderness decorated by 2 big green deer cages, 8 silver Havahart traps,
12 tan and gold snap traps, 4 bright blue stench cakes, and the last two foxglove
stems sectioned and lying carnage among the pathetic technology. Every last
ripening seed has gone to its doom.
I began to experiment with vole
exclusion cages. They are harder to make and harder to install – a cylinder
of half-inch metal mesh. I’m hoping they don’t need tops, because voles stay
low. One more “to do” during a busy time of year – yet they work.
Note from 2007: tried spraying repellent on the foxgloves.
Note from 2007: tried spraying repellent on the foxgloves.
2008:, all but three plants were destroyed by
voles. Those three plants wore the newly invented vole cages.
An
Angel from Darwin or God
Then a human miracle happened. A year earlier, mild-mannered
occasional volunteer Lisa Culp asked if there was more she might do. I hardly
knew her. She said later that I “baited” her with fringed gentians. Not
really. But I did tell her that deer and voles had been eating nearly all of
those rare beauties, and would she like to adopt them? Lisa, who sometimes
compares herself to “the Energizer Bunny,” made deer and vole cages for every
gentian, scores of them, a lot of work.
Lisa was celebrating a year of gentian success and
happily preparing for the 2009 gentian season when I laid before her the
plight of the foxgloves. She gave it some thought. Then the mass production
of vole cages began. In 2009, all large plants were protected. Probably as a result, in 2010 Lisa
had the great pleasure of being witness to a huge surge of foxgloves 178
plants – too many to cage – even for Lisa. Still, she caged scores of them.
Is this too much
meddling with nature? I sympathize with whoever answers yes. To land managers
and stewards who don’t want to do it, I say, “Great. Your site tests the No
Heroic Action alternative.” Yet the effort seemed good to us. Can it be
judged by the results?
2011 – now numbers have blown through the roof.
719 plants. Still caging as many as we can.
The graph below shows this population limping
along in very low numbers for many years. Then it seems to explode. By 2012,
we’re thinking that we may be “over the hump,” and perhaps so. But after you
pause for a happy look at the graph, see concerns below.
In one big way, 2012 was a failure! This year we rested on our laurels. We caged just a few. We concentrated our energies
on other species. Voles ate most Tomantheras without a vole cage – many
hundreds. We also lost about half the caged ones, probably to white-footed
mice. (Voles stay on the ground, but the rascally white-foots are great
climbers.) Maybe some foxgloves make so much seed that losing 95% of the
plants is good enough? Many species on the planet lose most individuals – to
something or other – and still prosper. Is it even possible that critters
actually help distribute seed in some way?
Our decades-long study was gloriously imperfect. It had to outlast changes in jobs, places of residence, life goals, etc. This account suffers from some lost data. But it sure beats doing nothing – or those neat and complete little studies of a year or two. Let me revise that: it offers something that shorter and “more scientific” studies don’t.
Next steps for the foxglove at Somme? We’ll continue to ask advice from the best experts we can find. We’ll probably broadcast the much-increased amounts of seed in various areas and record as best we can what seems to be happening under various management regimes. At some point, probably, we may just tell Tomanthera to sink or swim without our help. It will find niches, or not, and persist, or not. Best of luck, Tomanthera auriculata.
Speaking of "next steps" - a 2024 update on this 2012 post is here.
Credits
Principal credit for the
success of Somme’s eared false foxglove in recent years goes to Lisa Culp who
does most of the caging. She reports that she makes 16 vole cages per hour.
Great credit also goes
to Forest Preserve District of Cook County fire manager John McCabe who has
vastly improved the controlled burn program in recent years.
Thanks to Karen
Glennemeier, Ron Panzer, Gary Horn, John Balaban, Bernie Buchholz, Linda
Masters, Steve Flexman, Robbie Sliwinski, Doug Chien, Lisa Culp and many
others for edits and for their contributions over the years.
Photos
by Lisa Culp
References:
Center for Plant
Conservation: www.centerforplantconservation.org/Collection/CPC_ViewProfile.asp?CPCNum=6601
(Note that scientific
names change, and Tomanthera is also called Agalinis.)
Cunningham, Maureen and
Patricia D Parr, Successful Culture of the Rare Annual Hemiparasite Tomanthera aurucularta (Michx.) Raf.
Scrophulariaceae), Castanea 55(4) 266-271. DECEMBER 1990
Packard,
Stephen, 1988, Rediscovering the Tallgrass Savanna of Illinois:
digicoll.library.wisc.edu/cgi-bin/EcoNatRes/EcoNatRes-idx?type=div&did=EcoNatRes.NAPC10.PackardSavanna&isize=M
Swink
and Wilhelm, Plants of the Chicago Region, 1994.
END
NOTES
1. If anyone who lives
nearby would like to help on this (or some other) rare species, let us know
through “Comments” here or “Contact us” at www.sommepreserve.org. There are lots
of great experiments to try for anyone who finds this work compelling.
2. Some people think we
should not reveal the locations of rare plants. They may be right. There’s
danger of misbehavior if rare species locations are not kept within a limited
community. Botanical psychopaths may steal plants or seeds from known
populations. They may degrade, damage or destroy other populations or
ecosystems as they indulge in “copycat” vigilante efforts of their own
design. But secrecy can also kill. We need to build constituency and enthusiasm
for endangered species work; we need our ideas enriched by broad discussion.
Overall the best results may come from empowering more conservation than can
possibly be done by the grant-driven scientists and plodding bureaucracies
that, bless their hearts, do most now. This argument suggests the need for
“wiki” type safeguards, ethics, and communication. Your thoughts?
13 comments:
The honeycomb pattern on the seeds reminds me of morels. Is it to help absorb moisture from the soil, increase the amount of surface area to absorb nutrients and water? - Just curious. K
Oh, Kathleen, I love your question. I wish I knew the answer. Perhaps someone will have suggestions. In a prairie soil with highly developed crumb structure, this honeycomb surface could actually keep the seed separated from moisture etc. The plant is said to be partly parasitic. More surface for some parasite reason??? Also, many plants that, like this foxglove, are in the figwort family have weird seeds. It would be interesting to look into what that's about as well.
When I saw these seeds, I immediately thought the honey comb structure was a fire adaption. The insulating honeycomb should effectively protect the delicate embryo from extreme but quick heat.
In contrast to this rare grassland annual, most other prairie or savannah plants are long lived perennials. If long lived perennials have all their seeds killed by a fire, they have time to wait for a favorable season. Annuals do not have the luxury of trying again next year. This is likely the reason the seeds of Tomanthera and other Scrophulariaceae have evolved an insulating exterior structure. Having one of the few seeds that can survive a fire would be a significant advantage to a seedling following a burn. It is also likely that the honeycomb structure helps prevent germination until after a fire by excluding moisture (as Stephen mentions above).
My college Thermodynamics instructor would have been so proud of me for finding a novel application of the subject.
James
Interesting comments, James. A quick Google search produced quite a few research articles on the seed germination of Tomanthera (and other fire=adapted species). Many complex issues arise from those papers. It might be fun to research some this more (although I didn't notice any immediate implications for conservation decisions).
One implication for conservation decisions from germination studies is that the seed of certain plants, like many grasses, germinate strongest with the most robust seedlings when collected the season after a fire. In contrast, a number of forbs have lower germination and weaker seedlings from seed collected the season after a burn has occurred. The time of seed collectors is best spent collecting certain species from areas that have recently burned and other species from areas which have not burned recently. This does not relate to the Tomanthera specifically, but restoration efforts more generally.
What I have noticed was lacking in the literature was studies on seedling recruitment in the wild after the occurrence of a burn. This information would be useful to those who broad cast seed for restoration. Different species would be sown depending whether a burn was scheduled to occur sooner or later. Fire can have a significant effect on germination. It is well known that certain species like Ceanothus and Baptisia germinate better after heat treatment.
Considering the Tomanthera is hemi-parasitic and seems to like disturbance, I suggest conducting an easy experiment. I would sow seed on the surface of two areas where people and deer have been excluded. One area would be the control and have no treatment. The other area would have the surface disturbed by raking just enough to scratch or beak surface plant roots.
The reason I suggest the above experiment is an additional engineering use of a honeycomb structure is great strength. The structure of the seed might be evolved to protect the embryo from trampling. Trampling that might be necessary for this hemi-parasite to attach to the roots of a host.
James
James, more good thoughts. Thanks.
The experiment you describe sounds good to me.
Of course to do the above experiment you would have to have a population of seeds that had been trampled and a population that were not trampled in each area. It would be worth recording the faces of those on the Nature Preserve Commission when you told them you planned to take very rare seed and step on it. :)
James
You're a much better scientist than most.
This is a very thought-provoking post, Steve. It demonstrates the value of accumulating data over time. At my site Tomanthera stubbornly blooms during a period when one monitor goes on an annual vacation, so plants that formerly were counted in flower are now counted in seed. The predation of plants in seed that you so vividly describe may explain the observed drop in numbers. Yet the now continual presence of a hawk and coyotes on the site may indicate an evolving predator balance that requires no further intervention to maintain the Tomanthera.
Another observation is the apparent shift in the population center toward the wetter end of the prairie. Was that a one-time response to drought conditions? Is it a permanent shift, or just a snapshot of the continual migration of annuals? More data is needed - and more Lisa Culps!
Mark, thanks for the interesting observations. I too have seen species move around sites, perhaps because of wetter or drier years. Or hotter or colder, or early spring vs. late spring, or whatever. Sometimes it almost seems like some species don't like to stay in one place - as if they've used up something in the soil for now - or they only thrive in one phase of the constant cycling of successional states or sets of associates that seems so compelling in prairies, savannas, wetlands and (perhaps) oak woodlands.
Here is an interesting article on others who have tried to propagate this seed:
www.jstor.org/stable/4033421
John Cherry
After the Tomanthera reach higher numbers, do they help contain the sunflower and goldenrod populations?
To "Anonymous" on whether Tomanthera might "contain" saw-tooth sunflower or tall goldenrod: The quick answer is that I have no data nor even observations on that question.
If I were to speculate about it, I'd say that Tomanthera never seems widespread or robust enough to have substantial impact on such widespread, aggressive species. On the other hand, it would certainly be interesting to study what impact species like this have in recovering as well as in already high-quality communities.
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