It all started with a text message back in February. My friend and colleague Thomas Rainer was reaching out to ask if I had ever been plant exploring in Arkansas. He was keen to see Amsonia hubrichtii in the wild.
So, who is Thomas Rainer, and what plant is worth traveling from Washington, DC for him—or Nacogdoches, TX for me—just to see in the wild? Thomas is no stranger to the plant world. He and his coauthor Claudia West had helped galvanize the naturalistic planting movement with their book Planting in a Post-wild World. Now, they are business partners and integrate horticulture and ecology into their designs at Phyto Studio.
And, for the plant, Amsonia hubrichtii (Arkansas bluestar, thread-leaf bluestar, Hubricht’s bluestar) is beloved in the horticulture industry for its starry blue flowers that appear on top of the softest textured plant ever. Seriously, I just want to hug the feathery round-mound anytime I see it. And, then in the fall the foliage turns a brilliant caramel yellow. This species grows well in practically any garden situation minus deep shade or a flooded pond. And, while it thrives in many parts of the eastern half of the country, Arkansas bluestar is native to only 20 or so counties in Oklahoma and Arkansas.
Thomas wasn’t alone in wondering about this species. Amsonia hubrichtii had been on my mind this past year. I had been struggling with Arkansas bluestar here in Texas. In conversations with others here in the lone star state, the bluestar didn’t seem to quite like something. I know we are hotter than the Lurie Garden in Chicago, IL where it is massed and the John W. Nason texture garden at The Scott Arboretum in Swarthmore, PA where it provides soft billowy edge to paths. But, are we really that much hotter than Arkansas? I lacked the in situ knowledge, of seeing where it grew in the wild, and I suspected there was more to the situation.
So, we started planning a trip to see where Amsonia hubrichtii grew. I reached out to local plant enthusiast Eric Hunt. He is a member of the Arkansas Native Plant Society who I had conversed with on social media in the past about Arkansas flora. He had photos on Flickr of Amsonia hubrichtii blooming wild in the Ouachita mountains. We decided that late April into early May would likely be the best time to see Arkansas bluestar in flower, and we picked a weekend that best fit our schedules.
We met Eric mid-afternoon at Middle Fork Barrens Natural Site near Hot Springs, Arkansas. He was chipper to see us and show us around. In talking with Eric, we learned that he had moved around the country from Alabama to California, and finally ended up in Arkansas. He worked on computer systems, and on the side he enjoyed botanical expeditions and plant photography.
We approached the area from the south, walking one of those gravel roads that when a giant yellow school bus comes barreling by and picks up a cloud of dust, you are thankful there’s a stiff breeze blowing it away. Eric started talking to us about Middle Fork Barrens. He said botanists had known about the barrens for years, but it had only been recognized as a natural area since 2004.
As we walked, he began identifying our inquiries. An aster dotted the ground, and he shared that the barrens were one of the more eastern sites for the spring flowering Astranthium ciliatum (Comanche western-daisy). And, Valerianella nuttallii (Nuttall’s cornsalad) was everywhere as a nice dusting of white over the carpet of green.
Walking in we also saw our first of many Baptisia bracteata var. leucophaea (cream wild indigo), which occurred more often in shadier sites than I expected. I have seen the other variety Baptisia bracteata var. bracteata (long-bract wild indigo) near where we live in east Texas, and it was nice to compare it against this lighter yellow form with more upright flowers.
We reached the main entrance to the barren guarded by a fence and gate and made our way through a narrow opening on the side. Eric made a point to show us a borrow pit where locals had harvested stone in the past for various projects. It was here where a new to science Phemeranthus (fameflower) grew. Thomas commented on how this habitat created by humans made it possible for a species to grow where it might not have previously as the area around was covered in vegetation. This thinking can be applied to urban sites. We humans can have positive effects on creating habitat for unique species to grow.
We then climbed up through a lightly forested hillside to approach the Amsonia site on the other side of the ridge. Eric commented about how these shale barrens existed due to the soil being more shallow, and thus trees couldn’t grow, thus creating a “barren.” These type of barrens are different from others in the southeast like serpentine barrens where the soil has toxic levels of nutrients that prevent tree growth. Eric made a comment that while everything around us was green now, the barrens baked in the summer time.
As we walked up to the top of the ridge we passed Glandularia canadensis (rose vervain) and a new to me shade preferring Monarda species, Monarda russeliana (redpurple beebalm). Down the other side we passed a large colony of Symphoricarpos orbiculatus (coralberry). We emerged from the thicket and in front of us was an open valley, punctuated by a thin stream that ran through the middle. Eric teased that we were almost to the Amsonia.
We approached the stream where bold leaves of Arnoglossum plantagineum (prairie Indian plantain) grew amongst the matrix of green. And, rounding a copse we found the Amsonia in bloom.
I stood there for a bit just looking at the thirty or so plants that were up and down this short section of the stream. Plants were either right on the edge of the water or a few feet away, and we didn’t see any other Arkansas bluestar anywhere else at Middle Fork Barrens Natural Site. So, why? Why hug the creek edge when Amsonia thrives in a variety of sites in the garden? In cultivated environs, I would rank Amsonia hubrichtii more of a generalist, but here we saw a specialist at this site, a species that had a limited set of requirements for survival. How in the world it was ever thought that some scraggly thing growing alongside a creek could have so much horticulture potential, eventually being voted the 2011 Perennial Plant of the Year, beats me.
Eric made the comment this site baked as well in the heat of summer and these streams often dry up. He noted how Amsonia hubrichtii had thick, long deep taproots to help deal with drought, a trait I knew well from relocating my plant in Tennessee to Texas years ago. Perhaps that was the case. The waterway in the wild is where Amsonia can survive. To me, the thread-like foliage and round-mound shape were also indicative of adaptations for drought. Eric also said that for a species that evolved to grow near waterways that the thin foliage wouldn’t shred as bad in flash floods, as we could tell had happened from the slight down creek bend of the dead bluestar stems from last year. He added that one can also find Vernonia lettermannii (thread-leaf ironweed) with similar thread-like foliage in similar creekside habitat with Amsonia hubrichtii.
Eric offered to show us more of the natural area, and we gladly accepted. As we walked further north out of the barren, the habitat began to feel more like the eastern forests I knew so well. We saw Delphinium tricorne (dwarf larkspur), Polemonium reptans (Jacob’s ladder), Cynoglossum/ Andersonglossum virginianum (wild comfrey, although we have that in east Texas, too). A new one to me was Tradescantia ernestiana (woodland spiderwort), which has nice thick straps of verdant foliage. Eric said that it was a clump former and didn’t spread like other spiderworts. And, of course, jokes about Ernest P. Worell and Vern ensued.
We arrived at the middle fork that gave the barrens its namesake. Thomas began discussing the river scour habitat, areas where rivers would erode during flood events. We talked how these events could create habitats where trees and shrubs could find purchase while the herbaceous plant palette could be more variable. To my surprise I saw Rudbeckia laciniata (cut-leaf coneflower). I sold ‘Herbstsonne’ at the nursery years ago, but I had never seen the species in the wild.
From here we started back toward the cars. As we walked along, Thomas called out, “Oh, there’s Silene!” Sure enough in the dappled shade, we found the red star-shaped flowers of Silene virginica (fire pink). This habitat was different from the usual vertical Appalachian cliffs from which I had seen Silene growing, and them being scattered along the forest floor reminded me of the mass planting along the elevated walkway at Chanticleer. We discussed how some species like Silene regia had been investigated for being carnivorous. Eric commented how in thousands of years this species could be, too. All it needs is to develop a way for attracting insects to the plant and to make enzymes to break them down for uptake.
We returned to our vehicles, and thanked Eric profusely. It was a grand day for seeing not only Amsonia, but many other incredible species in such a wild and rugged environment. Next week, I’ll be back with part 2 of our journey to see Amsonia hubrichtii in Arkansas.