Canada Goldenrod & Wood Betony

 “What is the greatest gift? …something else - something else entirely holds me in thrall.  That you have a life that I wonder about…” Mary Oliver

I want to update our methods of keeping Canada goldenrod (Solidago canadensis) in check.  At right is a beautiful specimen surrounded by a diversity of other prairie plants (photo by Sandy Stark).

Some managers use a mowing or cutting schedule, either twice yearly or once a year when the plants are flowering.  Tom in his blog said mowing does not eradicate the goldenrod clones, but trichlopyr (20% garlon 4) does (August 31, 2011).  He described a “spritz” technique for killing the plants using a spray bottle of garlon 4 to very sparingly spritz just a few upper leaves.  Alternatively, Canada goldenrod can be cut, leaving a 12 inch stem that is then dabbed or sprayed with garlon 4.  We’ve found this latter method to be less messy in that walking through and around treated plants leaves fewer drips on our clothing.

The past five years or so we have been experimenting with two methods of Canada goldenrod control.  The first is to simply cut the stems in a flowering clone with a hedge shears once a year, not treating with herbicide, and repeating the cutting in subsequent years.  This is followed by burning yearly or every other year and then seeding with a mix collected from adjacent areas.  Seeds include but are not limited to woodland goldenrods, asters, black- and brown-eyed Susan’s, golden Alexander, ox-eye sunflower, monarda, showy goldenrod, hyssop, tall bellflower, milkweeds, savanna grasses, native thistles, bonesets, stiff gentian, and more, all generally fast-growing prairie or savanna species.  Wet-mesic species go into areas where the goldenrod is growing near the marsh.  These include lousewort (see below), Culver’s root, cup plant, mountain mint, dark-green bullrush, wool grass, meadow rue, gentians, great blue lobelia.  The rationale here is that herbicide, however carefully applied, always damages adjacent plants, eliminating competition.  In subsequent years, therefore, the goldenrod may rebound (see Chris Helzer - Prairieecologist.com/2011/08/19 - for support).  “Over seeding is a must,” and, to paraphrase, the vegetative spread of goldenrods increases with disturbance (Driftlessprairie.org). The Driftless Prairie managers also stress that goldenrod control be “multi-pronged” and will take years.  But they crucially remind us that this species sustains scores of important insects, so total elimination should not be a goal.  For us, this method has so far resulted in shorter, fewer and less robust goldenrod plants over the patient years.

Our second method of Canada goldenrod control is exactly the same as the first, with the addition of seeding the goldenrod clone areas with wood betony (Pedicularis canadensis) either shortly after collecting the seed, later in the season, or after spring burns.  At left is a wood betony specimen in flower (photo by Amanda Budyak).

Why are we trying this?  Several sources, including Luke Dahlberg, Citizens for Conservation, have written that wood betony helps control the prevalence of warm season grasses, such as big bluestem and Indian grass, as well as goldenrods and sunflowers.  The people at Prairie Haven say that “it seems to mostly affect Canada goldenrod” (5/25/2017), and use it along with mowing.  Tom also has weighed in:  “The role of wood betony in increasing diversity in prairies has been well established.”  It increases species richness (J. Torrey, Botanical Soc., Herbert et.al., 2005).  Richard Henderson has compared the function of wood betony to bison grazing (Proc. 18th N.A. Prairie Conference, 2003).  Wood betony has been shown to reduce the biomass of partridge pea and increase forb diversity and floristic quality where seeded (J.P. DiGiovanni et.al., Restoration Ecology, 2016).  We are now seeing wood betony flowering in amongst Canada goldenrod clones, and species diversity is slowly increasing with this method.

What is the secret?  Wood betony is hemiparasitic.  That means that is uses a host plant for nutrients, and also makes its own food through photosynthesis.  Not surprisingly, the plants it robs from are set back dramatically, allowing competitors to do better.  It has been shown to parasitize the roots of 80 species from 35 families (Piehl, 1968).  At right are areas of yellow-flowered wood betony in Toby’s Prairie in early spring.  Indian grass has been nicely tamed throughout this prairie through the years.  I’m sure that’s the result of many factors.

Hemiparasites do not take over an area, but tend to fade as their hosts weaken.  Or perhaps a balance of sorts eventually establishes itself.  You may be familiar with other hemiparasites such as bastard toadflax (Comandra umbellata) and lousewort or swamp betony (Pedicularis lanceolata).  We’ve been interseeding wetland areas dominated by Carex trichocarpa with lousewort for years.  Tom talked about this in his blog.  It’s also good for taming Canada goldenrod.  Somewhat like using a diversity paint brush in the marsh.  Toadflax has 40 different host species; we haven’t explored its potential as yet.  So much happens underground.

I’m wondering if we can use hemiparasites in our recipes for controlling woodland sunflower or pale Indian plantain, or?  I won’t mention using dodder, but…

“…your friend is your needs answered…” Kahlil Gibran, On Friendship

Blowing in the Wind

There is one pollinator and seed-dispersal agent as old as the Earth itself.  It’s everywhere:  the wind.  My symbol for the wind at left can be added to the hundreds easily found on the internet.  You might draw your own. 

Uplifting, breath taking, breath giving.  Breath:  our first act in life, and our last.  Inspiring and expiring.  We take it for granted.

 

Wind pollinated plants are called anemophilous.  Anemo, meaning wind and philous, meaning loving.  I like to think of it as the wind helping the plants in their love making, as opposed to plants just loving the wind.  Wind pollinated plants include almost all the gymnosperms (pine, spruce, fir) and also many of the grasses, sedges and rushes.  Others include oaks, pecans, pistachios, alders, hickory and walnuts.  Many of our food crops are also dependent on the wind for the spread of pollen:  rice, corn, wheat, oats, etc…..as many as 12% of plants in the world.  

Anemophilous flowers typically lack scent and are not showy or rich in nectar.  They usually produce lots and lots of pollen, most of which is smooth, light and non-sticky.  Some are flattened.  Some are winged for flight (pine, pictured above).  The stamens (pollen producers) are well-exposed to the wind, as are the large feathery pollen-catching stigma.

Insects sometimes do visit wind-pollinated flowers, such as oaks, grasses and corn, and of course birds come too to eat the insects.  Although lower in protein, sometimes bees have no other pollen choice.  Grasses are the most important producers of allergens in our area.  Many of us are especially allergic to reed canary grass pollen, whether we realize it or not.  Tap a seed head and watch in amazement the huge cloud of pollen issuing forth!  (I exaggerate.)

The wind is a very common and important seed-dispersal agent as well of course, not only in prairies, but also for tree species such as pine and maple.  The whirlybirds of the maple and pine are familiar.

Seed dispersal by wind is called anemochory.  Anemo, meaning wind, as we know, and chory, a suffix meaning to spread or disperse.  Plants using the wind produce lots and lots of seeds that are very light and often winged.  

Sometimes entire plants are blown around, like tumbleweeds.  Some seeds have hairy plumes, some have balloons, some fuzzy parachutes.  (Dandelion seeds can fly 500 miles, and the Javan cucumber seed, with five-inch papery wings, can glide more than the length of a football field - with no wind!)

Above are some of the anemochorous seeds we collect at Pleasant Valley, seeds we call the “fluffies.”  To name them and a few more:  liatris, goldenrod, asters, milkweed, ironweed, lion’s foot, thistles, joepye weed, ragwort, bonsets, pale and sweet Indian plantain, and on.  Grass and sedge “seeds” are small, light, papery fruits carrying one seed (achenes).  Of course, animals do eat and spread these seeds as well (zoochory), and the wind will even blow seeds around that have landed on water (wait for it…pleustochory, such as willows, and cattails).  Pleust means to sail or float.  And scientists must name things.  

At right are pine seeds liberated from their cones.  Below are seeds of big bluestem.  You’ve no doubt noticed that not everything that is blowing in the wind in seed dispersal is the actual seed.  In like manner, if you were to fly to New Zealand you would indeed be carried by the wind, but you would also undoubtedly be wrapped in an aircraft of some kind.  Similarly, seeds flying happily away from their parent plant are often surrounded by thin, papery ovary walls (grasses and sedges) and/or are attached to flower or leaf (calex) parts modified as feathery appendages, fuzzy parachutes, or wings.

Blowin’ In The Wind, by Bob Dylan (excerpt)

“…how many times can a man turn his head

and pretend that he just doesn’t see?

…and how many times must a man look up

before he can see the sky?

…The answer, my friend, is blowin’ in the wind.

The answer is blowin’ in the wind.”
 

There is a Season

 “To everything there is a season, and a time for every purpose under heaven.”  (Pete Seeger, 1959 and made famous as “Turn! Turn! Turn!” by The Byrds, 1965)

“A time to plant, a time to reap that which is planted….A time to keep, and a time to cast away.”  (Ecclesiastes 3:1-8)

Phenology:  the study of cyclic and seasonal natural phenomena such as migration, flowering, seed formation, spawning…repeated life cycle events.  Changes in the timing of these events from year to year reflect seasonal changes in temperature, moisture, disturbance, daylight and in the interconnections of the individuals living in an area.

I made this little table with its 2023 dates in order to inform this older person next year approximately when to collect some rare early prairie species and when to go after small areas of pesky weeds that I’m particularly suited to tackle (because focusing on smaller, picky tasks is sometimes better left to the slower moving).  You’ll note that some of the more “famous,” meaning in-your-face large, labor intensive weed problems, that even Pleasant Valley Conservancy still has, have been left out:  for example, garlic mustard, reed canary grass and the sweet clovers.  Amanda takes care, mostly, of the big nasties.  (This chart ends where July ends, but collecting seeds and weeding will be ongoing.)

Our website has a table of yearly seed collecting times for a much wider list of species: https://pleasantvalleyconservancy.org/seedcollectingtimes.html

At right are seed pods of Bird’s-Foot Violet (Viola  pedata) copied from Tom’s Blog.  I mostly missed the seeds this year, and noticed that Tom’s collecting time differs somewhat from my estimated times.  My chart is not his chart and these charts are not your chart.  You are making your own - to remind yourself to keep coming back.   Next year’s first wood lily blossom may be on June 5 instead of June 8.  I only hope I am there to see it, after a winter and a spring.  But if I miss it, I will not be so sadly at a loss as will the warbler who misses an early or late oak bloom, or the pollinator who emerges after the blossom wilts.

Asymmetric phenological shifts or mismatches, such as de-coupling of plant-pollinator or predator-prey interactions, are becoming more common as we warm the planet.  Hardly the comedy of my dog Luna not fitting (unexpectedly) through the cat door, but the misfortune of food spoiling before the guests arrive, of a bee waking up before the dandelions bloom, of baby birds needing insects that have already blown in the wind.

“In our sad mismatch, that unforgettable encounter -

that was never completed.”  (alkas poetry)

“…why, since these be changed since May, shouldst thou change less they they?”   (Elizabeth Barrett Browning, Change upon Change)