Where the Wood Thrush Sings

It's a sound that will stop me dead in my tracks, and turn my head like dog on point.  The song of the Wood Thrush.  Frozen, I listen waiting for the silence to break, half worried it might just be my imagination.  There it is again, the ethereal notes echoing through the woods and across the yard.

I drop my shovel and make a beeline for the thicket to the east of our house.  I pause and listen.  It is still far off.  The song is a bit choppy.  A few notes here and there.  Maybe it's just warming up.

I follow the fence up to the road and straddle the gravel shoulder.  Slowly I advance afraid I might scare it off, but the dense brush that hides this solitary performer must also obscure me.  

Now the song really picks up, and I am happy to provide an audience. 

My mind drifted back to when we first visited our new property.  I opened the door of the realtor's truck, and as I stepped out I heard the call of the Wood Thrush, one of my favorite (if not my top favorite!) birds.  Just a solitary note.  Nothing more, and since that hot July afternoon I haven't heard a peep.  No surprise there as I know it is a migratory species.  But, I have long wished to live in a place where one could walk outside and hear the trill of this passerine.  And for the past eight months, I've also hoped that first impression of our new property would not be the last.  The ee-oh-lay was certainly a good nudge saying, "This is right", and let's be honest, a small reason why I signed the closing papers.    

I started the short trek back to my planting, and throughout the day I was tickled pink to have it performing a natural oratorio with the ensemble of vireos, bluebirds, and gnatcatchers.  

I'm happy to live on an earth and happy to garden in a place where I can go outside and enjoy all that nature has to offer.  

Happy earth day, gardeners.  

“Whenever a man hears [the Wood Thrush song] he is young, and Nature is in her spring; wherever he hears it, it is a new world and a free country, and the gates of Heaven are not shut against him.”

— Henry David Thoreau

Discovering Blue Wood Sedge

Last fall, a plant caught my eye under the mammoth Magnolia grandiflora in our front yard.  Few plants save for moss can survive under its shade, but yet here was a grass ally holding its own.  Squatting down, I ran my fingers over the triangular edges and felt giddy.  It was a sedge I had never before seen.

Sedges are the "in" thing in horticulture.  Using Carex is quite fashionable now as green infrastructure, rain gardens, no mow lawns, and designed plant communities are all trends that capitalize on this incredibly durable species.  I have been searching high and low for the latter reason, good candidates to use as a ground cover layer in my plantings, and here was one right under my nose.  Well, my tree.  

The foliage was glaucous and broad, which limited it to a few species.  Searching online images and Carex keys made me believe that it was Carex flaccosperma (blue wood sedge).  But, with time I started leaning towards Carex glaucodea (whose common name is confusingly also blue wood sedge.  Why not call it glaucous sedge?).  Evidently Carex glaucodea used to be a variety of Carex flaccosperma, so I don't think I'm that far off.  And, the official taxonomic identity doesn't matter for the purpose I have in mind.  

Carex glaucodea/flaccosperma in a wooly part of our yard.  

I considered digging the single clump to propagate, but as with many flora finds, once you acquire the mental image it's suddenly everywhere.  The plants are primarily along the property perimeter—on the front bank, skirting fencerows, and under trees.  A few are actually hiding out in our lawn in full sun.  Frost made it easier to locate them as it browned the surrounding camouflage, and made the evergreen, glaucous blue blades easier to see.  With the arrival of longer days it's still easy to see from a distance.  The emerging foliage is colored honeydew and spikes above the turf.  

Back in November I started transplanting clumps into a bed along the roof drip line of our house, and recently, I finished filling it with plugs.  Any plant that can grow in such varied conditions warrants evaluation in the garden as we turn to using lesser known but ecologically importance species.  These relocated clumps will serve as a source for propagules and seed if the plants produce any.  In total, I moved over 100 clumps, and there’s still plenty more around our property.  

Saved from the mower blades, a wheelbarrow full of Carex ready for planting.  

Carex is hipster Liriope.  

Propagating all this Carex reminds me of reading in Larry Weaner and Thomas Christopher's Garden Revolution where they share how Native Americans would replant Carex barbarae (Santa Barbara sedge) as they dug clumps to use the blades for weaving.  And, as I re-wild our 2.5 acres of mostly turf, I’ll be sure to move some back into the landscape once I make more.

As far as the first plant that started it all, I left it.  I figured as a survivor under a mighty tree it should stay right where it is.  Plus, who knows how long it'll live if not moved.  We shall see. 

Chanticleer in Winter

During my recent escapade to Philadelphia to attend the Seed Your Future board meeting, I was able to visit Chanticleer in the offseason.  I love seeing a garden in each of the four seasons, and winter was one I hadn't witnessed at Chanticleer. 

If you haven't been to this pleasure garden in Wayne, PA, most horticulturists will tell you it is in their top ten favorites.   For me, I'm mesmerized each visit by how the gardeners weave creativity into plantings of both ordinary and extraordinary flora.  Even with the dearth of many flowers, forbs, and foliage, the garden still looked stellar.  Below are photos with comments along the way.  

The big takeaway for me from the visit was a reminder of the importance of incorporating strong lines into garden design and then maintaining them.  From this overlook view, manicured lines delineate areas, and different colors of the detritus enhance the contrast next to the torpor turf.  

A close up from the previous image taken from the bottom of the elevated walkway.  Here you can see different materials compose different beds.  Mowed ornamental grass in the foreground, and fall leaves in the ovoid beds in the back.  

The serpentine plays homage to the agriculture crops grown in the Pennsylvania countryside and features a different crop each year.  Even from a distance you can make out the bold curves of the bed.  

An upclose shot of the serpentine.  Again, look at how neat that border is between the turf and the bed.  

Curvilinear turf severs this sea of Sporobolus heterolepis.  The contrast between tamed lawn and wild grass already creates interest, I feel it is even greater now that winter color has manifested on the prairie dropseed.

It appeared that one part of the Sporobolus prairie had a test burn.  With the foliage removed, you can really appreciate the cespitose nature of the grass.  

With the dormancy and death of plants in the cut flower garden, curved arches provide drama when little remains.  I like to appreciate their importance by imagining their absence.  

One behind the scenes practice I witnessed was the staff's efforts to keep plants alive.  Here yuccas in the gravel garden were covered with plexiglass.  

And, here caged leaves insulate a tender banana near the tea cup garden.

A lone Schizachryium echoes the color of the blazing branches of Salix alba 'Britzensis' in the background.  

With the foliage gone, prickles on Rosa sericea subsp. omeiensis f. pteracantha (whew, that's a mouthful) are quite visible.  

A glance towards the pond.  Nary a weed to be seen.  

In all my visits I've never seen this three-foot-tall, stone pear.

A final shot of a prominent primary axis that runs part of the length of Chanticleer.  Such primary axes help to connect separate parts of a garden.  

Field Notes from Philadelphia: Seed Your Future & Longwood

SEED YOUR FUTURE

Recently, I travelled to the Philadelphia area for an advisory board meeting with Seed Your Future.  If you are not familiar with the movement, it is the green industry’s effort to increase the awareness of horticulture, and it was enlightening, encouraging, and exciting to see so many high-level hort heads pursuant in connecting more people to our gardening world.  There are some really cool announcements ahead from Seed Your Future, so keep checking the website.  Some of the the takeaways that I can share are below.  

My wife Karen who is a graphic artist tagged along with me on the trip and made this great illustration of the Seed Your Future hashtag #ilovemyplantjob.  #shesgotskills

• #DOYOULOVEYOURPLANTJOB?  We are all advocates for horticulture.  We can’t set behind our ivory hedges and expect horticulture to burgeon.  We need to tell everyone that #ilovemyplantjob.  As horteconomist Charlie Hall said during the meeting, "We need to show them what the world is with us."

• ALL IN A NAME:  The world horticulture is hard for some people to understand.  Terms like plantologist and gardenologist were thrown around, and from this very etymological base, we were encouraged to rethink how to make it easy to share horticulture with others.

• SEED YO' FUTURE:  We need to speak to students in ways that are understandable for them and make sense.  For example, instead of saying pursue a career in horticulture we can say put some horticulture in your career to help show students that working with a plants is an option.  I feel like Emeril Lagasse saying that encouraging students to bring some plant spice into their lives.  BAM!!!!!!!!!  I can't tell you the number of times that I've heard a student say, "I never knew that I could have a career in plants."  (It happened this past weekend at SFA orientation.)  My fifteen-year-old self was in that category once. 

LONGWOOD GARDENS

The meeting was held in Longwood Gardens conservatory.  During breaks and before and after the meeting we were encouraged to galavant through the gardens.  It didn't take much on those chilly Philly days.  Pretty pictures follow.  

We visited during Orchid Extravaganza, and per Longwood standards, everything looked stellar including this 12-foot-tall arch covered in Phalaenopsis orchids.  

Much of the conservatory featured the towering, yellow flowering Roldana petasitis.  Here it carpeted underneath by the coral, tubular flowers of Kalanchoe x houghtonii and the golden Euryops pectinatus.

It's amazing to have all this color inside when everything outside is dark green and brown.  

I encountered an old friend in a cooler part of the conservatory.  I fell in love with the exploding flowers of Scilla peruviana years ago at the JC Raulston Arboretum.  Fun fact, it is not from Peru but from Africa.  Linnaeus named it so because the specimen had a note about "Peru" on it.  That was the name of the ship carrying the cargo.  

I liked how Longwood espaliered fruit trees on fencing material in one of the cool houses.  Such an easy option for the homeowner, too.  

When you go to Longwood and you have to "go", you'll find the restrooms are nestled amongst the largest green wall in North America.  

Stalwart Asparagus

Asparagus is a real stalwart, evidenced by the times I’ve seen it in road right-of-ways and farm borders.  My first encounter was a clump catching the breeze off Highway 22 that led to my grandmother’s house in Tennessee.  While I thought this lone survivor from an old timer's garden was a fluke, I’ve since seen the frilly fronds on roadsides in Arkansas, North Carolina, Georgia, and Texas.  

Asparagus also thrives in the north as seen here at Chanticleer.  

They aren’t native.  No, these old landrace plants are relics of yesteryear, markers of some old homestead or the final brush pile containing said homestead.  In these places it has survived abandon and bulldozer and seems to do just fine as the stem slithers under the surface of the ground, gaining a bit more purchase each year. 

The true stem, that is.  Most people call what we eat stems, but the spears are actually called cladodes, modified leaves that resemble a stem.  If you ever want to check, damage the asparagus’s foliage top.  New shoots don’t originate from the fronds as they would from stem tissue.  Instead, they pierce upwards out of the ground from the rhizome.  

These remnants may not be the supped up cultivars we see in seed catalogs today, but they are still delicious.  Asparagus's culinary essence seems to attract all the attention; however, the plants are quite ornamental, an epiphany I had when I saw in our SFA Sprout garden two falls ago asparagus's senescing canary-colored foliage next to blue, bold Rudbeckia maxima.  It was one of those color combinations that gives you pause in the garden and makes you ask, “Why didn’t I think of that?”  The autumn color and the plant's dainty foliage lent to its installation as a see-through structural interest plant in the food prairies on campus last spring.  The leaves on some individuals reached six feet tall before the end of the summer. 

I'm sure I'm not the first to appreciate Asparagus officinalis's texture and color attributes, but I feel like it.  A plant that you can see going 70 mph down the road warrants more use in ornamental plantings.  I don't think I've ever heard of using asparagus as a perennial like I have the tomes on Rudbeckia, Phlox, and Hosta.  I suppose that's because it "only belongs in the kitchen garden."  Rubbish.  

Nestled amongst Bouteloua, Symphyotrichum, Liatris, and more, one might not immediately notice the Asparagus in our plantings.  But, in the fall when the foliage fades gold, it hides no more.  It will hold a light yellow/tan color for the rest of the winter.  

I didn't even mention the flowers.  While they are no bigger than a rice grain, small pollinators like to jump from blossom to blossom.  The plants are different sexes.  You need a male and a female for fruit set.  The red fruit are usually not preferred since they take away energy from the spears, but if you're using the plant for ornamental purposes, have at it!

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This week, I planted asparagus into our kitchen garden at the house with the end goal of contrasting the fine-textured foliage with herbs and low-growing perennials.  A few students helped me collect some wild plants (thanks Aries, Jade, and Jevon!).  

Dividing the mature clumps took some finger work.  The rhizome can be separated into smaller pieces.  The five clumps we dug resulted in about 16 propagules, each with solid, off-white roots and a few buds.  Finding the growing buds, which resemble turtle heads just poking out of their shell, was fairly easy since on most specimens the remains of last years foliage were visible.  Broken up, the crowns look like they belong in Animalia, resembling a jellyfish with long tentacles.   

A clump just after excavating

Pulling the rhizome apart

See any turtle heads?  Then you've found the buds!  If you need a hint, one is at the base of this large out-of-focus root in the left corner of the photo.  

Planting was a breeze.  One has to go wider than deeper.  I prefer to shovel soil out of the first hole, situate the crown, and then use soil from the next hole to fill the first.  The last hole gets the first soil.  Before watering and mulching, I made sure that the buds on the crowns were visible or close to the surface.

Jellyfish washed up on shore?  Nah, just asparagus crowns ready for planting.

By the end of the summer, they’ll form a swaying, verdant wall enjoyed in our side porch rocking chairs for years to come.  Who knows?  Maybe a century or two from now some other lad will find them and ponder from whence they came, and maybe he or she will enjoy how delectable they are as both a feast for the mouth and the eyes.  

Field Notes from Connecticut, January 2018

When I travel, I always report things I’ve learned to my students upon my return, and in the spirit of education I decided to start sharing these field notes from my trips on the blog. 

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This past week I travelled to the frigid north to speak at the Connecticut Nursery and Landscape Association on engaging millennials in horticulture, and after an enchanting trip I wanted to share knowledge I gleaned from my excursion.  

 

GIRDLES ARE HURDLES

Rick Harper from University of Massachusetts Amherst spoke before me on how production influences tree survival.  He sees many cases of stem-girdling roots in trees in the landscape, a paradoxical condition where life-giving roots end up strangling the plant.   He reminded the audience to watch for causing this disorder when installing trees.  The disorder can occur on some species during production when roots in the pot grow out, hit the side, and then begin to circle.  What I learned is that in others like Acer, it may be due to planting the root flare too deeply.  If not corrected by slashing or disturbing the rootball or by planting at the right depth, the girdling roots can eventually result in poor health in the tree.  

BROKEN ARROW, PERFECT PLANTS

Caleb Melchior reminded me that Broken Arrow Nursery was in Connecticut.  Once I found out it wasn't far from where we were staying, I took Adam Wheeler, Broken Arrow's plant development guru, up on a previous offer to visit if I was ever in the area. 

Once we arrived, we bundled up for a brisk but sunny walk through the display gardens and nursery.  Near the entrance we passed a massive Larix kaempferi 'Pendula' that was planted in 1960!  Adam hinted that it was likely one of the largest in the US.  

Larix, Larix, let down your hair, so that I may climb thy golden stair.

Adam said that diversity is king at Broken Arrow, which is quite evident once you enter a greenhouse.   They have over 6,000 different taxa on the property, many offered as both retail... and mail order options!  Adiós, paycheck!  

As we walked in the the plant-packed, solar-warmed cold frame, my eyes wandered through potted shrubs and perennials.  One of the coolest plants I spied was ×Didrangea, a new-to-me cross the national arboretum made of Dichroa febrifuga and Hydrangea macrophylla that may have a chance in east Texas since both parents perform decently for us. There was also Acer conspicuum 'Esk Flamingo'.  I fold for great winter stem color on woodies, but alas, my appreciation must remain in the north and the Appalachians as most of them don't fair well in Zone 8.  Yes, I know.  I need to give 'White Tigress' a try.

Adam Wheeler is all smiles in his element.  

Nerds, anyone?  The candy that is.  The grape-colored buds on ×Didrangea tease a taste.  

Snake-bark maples tempt me to make a purchase, but alas they wouldn't fair well long in Zone 8b.

Back outside Adam recounted that history of the nursery.  It was started by Dick Jaynes who worked on Kalmia latifolia breeding for 25 years, and upon retirement, he opened the nursery in 1984.  As was briefly mentioned earlier, Adam’s role is plant development.  He stays on the cutting edge of what’s new and what’s been found to help the nursery keep its niche.  

On the east side of the nursery, we paused to enjoy the spectacular view of the low mountains of Connecticut with the sun hovering over Sleeping Giant Mountain.  Off to the side was a solar panel that impressively powered electricity in the main house and heat in the greenhouses.  I appreciated them as a nursery leading an effort toward sustainability as I feel all of us should be doing.  

Photosynthesis and artificial photosynthesis powers Broken Arrow, each in it's own way.  

One take away for our operation at SFA was this nifty stack of pots to educate customers on the different sizes of pots.  As anyone learning a new craft language, customers (and students!) don’t always understand logistical terms like gallon pot or three inch pot.  Having something visible and readable helps ease any learning pains.  

The leaning, learning tower of pots.  

 

HORTICULTURE.  EVERYWHERE.

I never knew that Connecticut was so agricultural!  While I had a brief visit once before, this time was the first I really got to explore the state.  It was charming seeing all the rustic farms and barns.  It seemed every road had this quintessential New England feel, and in every small town we saw a farm stand, garden center, or farm store.  Many were closed for the season, but in discussions with people I learned they come to life after the thaw.  Locals told me that there was a demand for plants in all forms, partly because Connecticut is New York’s playground.  As I left the state, I wondered why can’t we have more communities support small agricultural enterprises?

 

SIGN, SIGN, EVERYWHERE A SIGN

One of the inspiring things I also saw was that many nurseries, farms, greenhouses, and vineyards were featured on a Connecticut Grown sign.  I began thinking back to many of the side roads and city streets I’ve explored searching for a garden center.  I wondered why more states don’t do this?  And, if they aren’t willing, maybe garden centers, farm stands, etc. should put more signs up so that passers by at least know they exist?  There's power in alerting people that you exist.  

 

A BLANKET OF NEEDLES

While visiting Washington Depot to let Karen get her Gilmore Girls geek on, we saw a great use for your old Christmas trees.  Chop the branches off and lay them down to protect plants.  While in this setting the coniferous cover was for herbaceous ornamentals, the minute I saw the foliage I recalled how Eliot Coleman once wrote that spinach covered with evergreen boughs had a 90% survival rate while those uncovered only saw 10% survive.  I think it looked pretty, too.  

Such a lovely carpet of green!  Better than bare soil or mulch.  

Another fun tale from Washington Depot.  The bookstore The Hickory Stick Bookshop had an incredible selection of gardening books.  AND, IT WAS VISIBLE FROM THE FRONT DOOR!  Not tucked away in some obscure corner covered with cobwebs.  

 

A FEW PRETTY PICS

Connecticut roadsides offered many places to stop and pull off for photo ops.  I leave you with a few favorites.  

Happy Anti-privet Day!

“The only thing necessary for the triumph of evil is for good men to do nothing. ”

— Edmund Burke

Now that a hard freeze has descended on east Texas and erased the deciduous foliage from the landscape, the evergreens radiate in thickets and pastures alike, their verdant foliage an afterglow of warmer days when the world was all green.  

Most of these I like.  Eastern red cedar I adore.  Pines are ok.  I have an aversion to the shroud of needles they drop, but I love when wind whispers through them.   Even honeysuckle I’ll leave to make the flowers into sorbet.  

Sparse now, but once it leafs out in the spring, privet casts dense shade.

But, the one emblem of green I hate seeing more than any other in this dearth landscape is privet (Ligustrum sp.).  The scourge is everywhere and is a horticulturist’s nemesis.  The evergreen, shiny leaves cast dense shade preventing the growth of native plants below.  The emerald glow that does make it through isn’t enough for species to germinate or grow.  Some creature could eat it, but I’ve read due to distasteful compounds the leaves aren’t tasty to animals save for deer.  Now if only we could train these prized-plant-devouring, four-legged pests to eat only privet two of our problems would be solved!

Privet spreads like a plague upon the land near and far.  Rhizomes locally increase the pestilence, and it’s indigo-colored berries are feasted upon by birds and the seed spread by their wings.  Those seed not eaten drop below the mother plant, sprout, and create a carpet of minions .  

My first encounters with privet were at my grandmother’s house where I had my first vegetable garden.  I would hack the branches and use them for stakes.  Yet, sometimes even these limbs would attempt resurrection by sprouting shoots and roots.

It is so depressing to see a plant that we humans introduced for utilitarian purposes—to create living fences and hedges—now in some ways has a mind of its own.  It is taking over our land and erecting its own barriers, similar to the stories where robots we brought into being have become self-aware and gone astray to create a post-apocalyptic world.  

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There. is. hope.  Research shows that removal of privet results in the return of native species. 

We should have an anti-privet day, a day when people and communities go out as a mob with pruners, loppers, machetes, axes, and saws to eradicate this species.  I vote sometime in winter when it can’t hide in the smokescreen of foliage,few other garden tasks occupy our time, and most ticks and chiggers slumber.  It doesn’t have to fall on a set cardinal date every year.   A warm, sunny day will do where working outside for a bit will welcome the removal of a jacket.   

Before privet removal.

After privet removal.  Hey, there's a fence there!

I’ve been celebrating a few anti-privet days.  At our new property we have a few behemoths along our fence rows, but most are spindly young whips.  I’ve been eyeing their demise since we first moved in August. 

Small switches are easy.  A swift stab through the earth with a heavy shovel will make quick work of the job.  Larger beasts require a cut back approach.  They will sprout up in the spring, but a shot or two of glyphosate will kill the Hydra heads.  Be cautious cutting near or through barbed wire as the metal pricks can grab your clothes and you.  

Once cut straight branches can be used for trellising and staking material.  The rest of the refuse goes on a burn pile.  

A good afternoon's work.  There's more privet rubbish that's not visible past the pile in the back.  

Clearing along our fence row I had the idea of planting a fruiting shrub like a native Ilex or Sambucus where I rip a few out so that the birds have something to sustain them and tempt them more than privet in the future.   

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The east fence row is now clear of privet, and the north side is next.  The perimeter of our yard will soon be free of this curse.  Sure, there will be a few renegades I missed.  But, in the words of Seth Godin, I’ve put in the work and positively impacted my little microclimate.  I look forward to next winter when the deciduous leaves once again drop, and maybe the only verdant foliage I see will be the desirable evergreens.  If a few privet remain or have since sprouted, then I'll celebrate another anti-privet day.  

Maybe you should celebrate anti-privet day, too.  And, tell or bring a friend.  

The Avoidance Zone

Don’t you love learning?  Wrestling with a concept, and finally putting the puzzle pieces together to see the bigger picture.  That’s been me lately with this amorphous concept called the avoidance zone.  

Well, longer than lately.  It's been something I've wondered about since childhood, but I didn't know it was called that. 

Growing up in west Tennessee I loved to go romping o'er hill and dale searching for wildflowers.  But, finding any was rare.  I can count on my hands and toes the number of really unique native wildflowers I found within a mile of my house (Erythronium albidum, Trillium recurvatum, and Phlox divaricata near the old creek; Arisaema triphyllum in the woods by the river; and on roadsides and in fencerows Tipularia discolor, Yucca flaccida, Vernonia gigantea, Podophyllum peltatum, Sedum pulchellum, Pycnanthemum tenuifolium, and Rudbeckia sp. along with a few other yellow Composite species I never keyed out.  That’s pretty much it. 

I felt so gypped. These books I read showed forest floors and prairies covered with a plethora of plants and blooms as far as the eye could see. Even traveling east towards Nashville you could see Trillium and Geranium going 70 mph on I-40.  I lived in the country.  Rural America.  There should be ample flora for a budding young botanist.  

Why weren’t there more wildflowers in west Tennessee?  It wasn't that we couldn't grow plants.  What flora was there grew very well.  We had fertile soil, and we received abundant rainfall.  I felt I should be finding more.  Go east or west, and the number of different kinds increased.  I assumed the reason why was because the region had been farmed to death.  Fields and pastures now occupied my would-be floral dreamland.  

But, had the species diversity been richer before conventional agriculture arrived on the scene?  I wasn’t certain.  Richer, of course, in a technical sense.  Species richness is an evaluation of how many DIFFERENT types of species are present in an area.

Once in a conversation with one of my undergrad professors Dr. Nancy Baushaus, it arose that the same phenomenon is observed with mammals. The further you go east toward middle Tennessee or the Ozarks westward, the richness of mammals increases.  This observation followed the same trend as what I saw with flora and made sense if we assume that the upper levels of the food pyramid are limited in their richness by the layers of species beneath them.  The pyramids in Egypt don’t get wider as you climb.  

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A few years after I left home for grad school I became aware of the Biota of North America Program (BONAP), a great website for finding county-level distributions of plants species. With that data they help visualize what species occur where, and they can run analysis to see the richness of species diversity in different regions. Browsing the website I discovered this map...

All credit to Biota of North America Program for generating this informative map.  While a legend doesn't exist for the map, green has the highest number of plant species followed by lighter greens and yellow, followed by tans and browns for lowest diversity of native vascular plants.  There is more information on the website about the terminology in the map.  

...and that I had been living my childhood in a region called the… dun dun DUN... AVOIDANCE ZONE.  It's like a little yellow desert island in a green sea of vegetation in the south.  Maybe the dearth of wildflowers wasn't my imagination.  Maybe there was something else going on here.  

But, what?  And, what is this thing called an avoidance zone?  The BONAP website states it is where "flora [is] limited by [a] lack of suitable habitat for a diverse flora, whereby widespread species may have a range gap in this area rather than having its own flora.  

The inner first grader in me came out yet again as I asked another why.  Why a gap?!?  There's plenty of resources in west Tennessee, especially with decent soils and ample rainfall.  Years passed as this question sat on the back-burner in my mind, occasionally being stirred from a conversation here and there with a colleague.   

Enter Thomas Rainer.  He turned my mental stove up to high when he presented at Speaking of Gardening in Asheville this past August.  Rainer said during his talk that stresses in a landscape actually increase plant diversity.  

Wait, what?!  Why would stress increase diversity?  It seemed to go contrary to everything that I knew about organisms in their environment.   If environments are too stressful, then hardly anything can grow well.  (*Cough* Antarctica *Cough*)

Several Google searches later with keywords including species and stress and diversity yielded nothing.  But, here is where things got interesting in my thinking.  I flipped the increasing-stress-then-increasing-diversity hypothesis on its head and asked, "If stress increases diversity, could an absence of stress or low stress decrease diversity?"  I.e. better conditions resulting in less types of plants growing in a region.  Perhaps, but again I wanted to find hard evidence why.

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A few weeks ago, I started reading Sowing Beauty by James Hitchmough.  (Side note:  I’m only a few pages into the book.  It’s a great, great read if you want to learn more about how ecology can influence gardening.)

I found the answer!!! 

James wrote that resource-rich environments have low species diversity because the competitor plants present outcompete other species (see my prior post to learn more about the three survival strategies of plants). That’s what they’ve evolved to do, to use resources more efficiently.  And, with their resource-harnessing prowess, they tower over others and crowd them out.   

Mind. Blown.  I think competitor species created the avoidance zone.  West Tennessee habitat is suitable, perhaps too suitable.  I was amazed that it could be not directly due to resource availability or habitat suitability but an indirect effect from some species being resource hogs.  

On a whim, I started looking at factors for plant growth across the country like soil fertility.  The map below was created by Bradley Miller, Randall Schaetzl, and Frank Krist, Jr. (researchers at Michigan State University and United States Forest Service) to illustrate how productive soils are.  Orange soils are less fertile, pink is in between, and purple/blue soils have the highest fertility.

All credit to Bradley Miller, Randall Schaetzl, and Frank Krist, Jr. for their incredible work creating this soil fertility index map.  The link in the caption provides a more detailed legend, but again yellow/orange soils are least fertile, pink is in between, and purple/blue soils have the highest fertility.

To compare with the original BONAP map, I overlaid the two and created the nifty gif below. 

Psychedelic, huh?  While I haven’t done any statistical analysis, it appears that patterns exist between the two maps.  As soil fertility increases (map gradients go from yellow/orange to pink to purple/blue), the species diversity decreases (map gradients go from green to yellow to brown).  A few that popped out to me are listed below.  

• Orange on the soil fertility map corresponds with green/dark green in the Ozark Endemism Zone, Southern Appalachian Endemism Zone, Apalachicola Endemism Zone, and Coastal Appalachian Tension Zone.

• Lower Mississippi Alluvial Avoidance Zone (aka home) is pinker in soil fertility than surrounding orange regions and has yellow/tan species diversity compared with the surrounding green/yellow green areas.

• Great Plains Low Diversity Zone has a blue/purple color for soil fertility and tans and browns for species diversity (notice the orange spot in Nebraska where species diversity actually goes up a little)

Of course, soil fertility won't explain the entire interaction as there are other factors that influence plant growth, and not every part of the map follows the colors exactly.  But, I can see patterns, and this observation helped me answer why we had low species diversity in west Tennessee.   

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The concept that at some point decreasing resource availability and increasing stress species has to result in a drop in diversity still bothered me.  It is just logical, so how do we fit this thinking into a plant community model?

I was looking up some information recently on John Philip Grime who conceptualized the competitor, ruderal, and stress-tolerant model, and I came across his hump-back model of species diversity that really neatly wraps up much of what I've been mulling over since my childhood. 

Figures from Michalet, R. and B. Touzard.  2010.  Biotic interactions, biodiversity, and community productivity, p. 59–78. In: Francisco Pugnaire (ed.). Positive Plant Interactions and Community Dynamics.  CRC Press, Boca Raton, FL.

Grime used data he collected from British plant communities to generate the above models.  Curve B is of interest to this post.   Again, species richness is an evaluation of how many DIFFERENT types of species are present in an area.  As environmental stress increases, competitors can't grow as well; therefore, other species that can handle stress can survive.  However, eventually the stress becomes so great that even the stress-tolerant species begin to decrease in number. 

If you'd like to know about Curve A, it represents increasing management/disturbance.  The more frequently plants are killed due to fire, flooding, etc. decreases the competitors so that other plants can grow; this stress increases diversity until the disturbance becomes so great that even the ruderal species decrease in number. 

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So, what’s the application of this?  If I’m a common gardener, what do I care?  

One is a repeat of what many have been writing—stress can be and is an asset in our gardens.  We have a "more" mentality for the resources our plants need like water and fertilizer, but perhaps stressing things a bit would help us be successful with more species. 

I also think understanding this hump-back model can make us better gardeners and designers in combining different species together.  If we have a sense of what survival strategy a species uses, we can make sure that we aren't creating mini-avoidance zones in our gardens.  

Finally, I don't think that the area I grew up in should be called the avoidance zone.  I mean if you were a plant would you want to grow in an area called that?  Kidding aside, yes, the region is a gap between higher species diversity areas, but I don’t think it accurately explains why.  Plants were not avoiding west Tennessee.  They were just being outcompeted.  

2018 Garden Plans

It’s the new year, and we are excited to see the ideas we have for our homestead sprout, grow, and blossom.  I have much I want to accomplish this year, and to really hone my focus, I recently sat down and wrote out my big goals for the new year.  

MAKE A BASE MAP.  Over the holidays I constructed a base map for our smallholding so that we can plot and plan where the different gardens and production areas will go.  Using the survey information, I’ve created in Illustrator a polygon that perfectly fits an underlaid Google map image of our property.  It was amazing for me inputting the shape's criteria only to find that it seamlessly fits our fence rows.  The next goal is to get the trees on the property mapped with their identities.    

FENCE AND PLANT THE ORCHARD.  The orchard has been an area that we have started transforming this fall.  It’s a full sun area with fairly level topography save for a slight rise on the southeast corner.  The area is backed to the north by a haggard fencerow, lined with mature Liquidambar, Juniperus (one of which has absorbed the old, rusted wire), and Quercus.  To this fence row we will attach two perimeter fences about five feet apart to keep out the dastardly deer.  The outer will house brambles and the inner muscadines. Within the inner fence, the long term plan is to plant fruit trees such as persimmons, apples, and peaches and fruit shrubs like blueberries.  While we wait for the woodies to mature, we will be growing edibles and cut flowers in the open areas, which is our current plan for this summer.  There’s been several small trees—random Lagerstroemia and Quercus—to remove before we can plant parts of it, and I’ve already cut down and quartered four of them.  I hope to be ready for planting with fruit trees late this spring, but next fall is more likely.  

EXPAND THE KITCHEN GARDEN.  Our kitchen garden right outside the kitchen door has been a delightful and delicious project this fall, and we will begin expanding it southward to grow more this year.  I need to cut down a spindly red maple that was planted there before we arrived.  It’s too big to move and had very poor color this fall.  I’ve been toying around with the idea of espaliering fences from figs and perhaps other fruit trees.  On the list for growing this year are tomatoes (of course), pole beans, peppers, sweet potatoes, sweet peas, southern peas, and more.  The seed orders are already in progress!  

BUILD A CHICKEN COOP.  Years ago when Karen and I were dating, I hid a book about raising poultry in her Christmas presents as a joke.  We laughed it off, but lately she’s been talking about wanting livestock like chickens.  Perhaps the prank planted a seed!  We both have talked about how they will be good for egg laying and picking pests out of the gardens.  The locals have recommended Black Sex-links.  Building the coop will likely be a summer project.  I’d love to have a mobile one with wheels that we can move throughout the property.  

A PERIMETER OF ANDROPOGON.  It took me a while to decide on what plant should surround our wrap-around porch.  I wanted something showy and attractive but nothing too high to block our view.  When we moved in, giant meatball Camellia and Loropetalum (yes, I know…) blocked the view of the house as well as vistas out our bedroom window.  These have slowly been making their way to the burn pile, save for the Camellia that I want to move to our winter garden.  I iterated through a variety of other options like Hydrangea quercifolia and Carex until finally one day the perfect fit hit me—Andropogon virginicus or broomsedge.  This grass has been a favorite of mine since childhood.  The auric strands in the winter sun look as if Rumpelstiltskin wove them himself.   Sitting on the front porch earlier this year I imagined watching the culms dancing in the wind next autumn in the low sun's vanilla rays and casting shadows on the front porch concrete. The planting will only be about four feet wide, the formal lines lending a modern yet wild look to the log cabin.  The seeds of course will come from local stands up and down the roadsides nearby.  I plan to start cutting sheaves soon before the seeds dislodge.  I imagine also plugging in some early Narcissus and self-sowing bluebonnets for early season color.

OPEN THE GLADE.  As I wrote about in a previous post, east of the house there is a mishmash scattering of woody plants that I want to move to open up the area and create a glade.  It’s a beautiful setting for an outdoor venue for parties and get togethers.  Most of the plants shouldn’t be too hard to relocate. The largest is one of hybrid Magnolia known as "the girls".  I’m not sure which cultivar it is yet, but it will be moved just a short distance to our front shrub border.   

COLLECTING AND PROPAGATING PERENNIALS FOR THE PRAIRIE.  The last big goal of the year is to accumulate and increase the number of perennials for a future prairie installation west of our house, probably in 2019.  An online order here, a stop at Big Bloomers last week in North Carolina there, and I’m well on my way in creating a grassland here in east Texas. 

That's enough to keep me busy for a while.  Good luck to all of you other there pursuing your #lifegoals.  

The Waiting Period

It’s hard.  It's hard to wait for plants to grow.

We want seeds to germinate now.  We want cuttings to root now.  We want fruit trees planted yesterday to bear fruit now.

Our industry spends countless hours and investment trying to short this propagation and growth process.  But, no matter how much research occurs, there will always be a waiting period.

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It’s hard.  It's hard to wait for people to catch the gardening bug. 

We want millennials to garden now.  We want the number of young people that come into our garden centers or horticulture programs to drastically increase now.  We want advertisements and sponsored social media posts from yesterday to bear fruit now.

Our industry spends countless hours and investment trying to shorten this propagation process.  But, no matter how much research occurs, there will always be a waiting period.

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The waiting period.  That's where the magic happens.  You can't always see what's happening beneath the surface, but that doesn't mean that nothing is happening.  It's where dormancy blossoms into life and roots take purchase in the soil, where wonder is imbibed and brown thumbs become green. 

The key is that we keep propagating and cultivating.  Every day do something that will help horticulture grow, plant-wise and people-wise.  Yes, it will take time for results to come from the pipeline, but that's ok. 

We are willing to wait.