Big Spring Plant Survey Flora Data and Discovering Texas Tree Ring Science

The former Jenkins Farm as it looked during tree clearing for the future Texas Horse Park. Pictured are Sean Fitzgerald with the orange helmet and Tim Dalbey who are extracting tree trunk samples from a huge downed Post Oak estimated to be over 150+ years old

The rough edged realities of progress come quick to large construction sites. What man built and has stood for a century is reduced to scrap over the course of an afternoon. What nature took centuries to grow falls in the fraction of that. It’s a dramatic farewell that bulldozers often orchestrate, a permanent change of landscape. Caught in the middle of all that are unseen gems of history that at some point will help Dallasites understand not just the past but where we are headed in the future.

In 1846 Sam Houston gave a speech on the floor of the United States Senate entitled A Tribute To The Indians “As a race they have withered from the land, Their arrows are broken, and their springs dried up;……Ages hence, the inquisitive white man, as he stands by some growing city, will ponder on the structure of their disturbed remains and wonder to what manner of person they belonged.”

Dallas is fortunate to have a handful of very dedicated private citizens who fit the bill of what Sam Houston spoke of so long ago. Nowhere does his speech ring more true than the woods surrounding Big Spring in the Great Trinity Forest. The Yeoman’s work here over the last year to discover the centuries of history and the combined preservation efforts will have a far reaching legacy for generations to come.

Through some very hard work Big Spring will become an official Dallas Landmark. Believed to be the first natural landmark in the City of Dallas, landmark designation is traditionally given to buildings, places and physical things. This new landmark, still in just the formative infancy of the process will be unique in what it represents, a rare natural spot ripe with the complete story of Texas at ones feet.

The story and the people involved in the awareness and preservation is rather remarkable and maybe someday once the dust settles some the background of how this came to be will be shared to a greater extent. As of this writing much is still in Square One with regards to how it will all shake out, written on bar napkins, sketched into dirt drawings with a stick and what amounts to over a thousand emails.

Part of that hard work includes some rather obscure data collection and preservation of tree slices from an old Post Oak trunk and a continuing cataloging of plant species around Big Spring.

 The Big Post Oak at 811 Pemberton Hill
The dying Post Oak at 811 Pemberton Hill Road as it looked in June 2012

For as long as there has been a Dallas, a Post Oak tree has commanded the high terrace of the Trinity River Valley in Pleasant Grove. From the spot one can see west clear to Oak Cliff,The VA Hospital, Fair Park and Downtown Dallas some miles distant.

The tree is most likely more than 150 years old and witnessed the first surveyors, Texan explorers, pioneers and settlement of this very spot. The Beemans, Bryans, Pembertons, Kirbys, Jenkins, Cantrells and Jassos made a living under this tree as it served as part of their farm and ranching operations over the better part of two centuries.

The rainfall, the weather, the heat of the summer and the cold of the winter that all those families saw over the last two hundred years are recorded in the tree trunk of that old tree.

Post Oaks Quercus stellata are extremely sensitive to root disturbance and lack of oxygen in the root zone, so construction activities that compact the soil, pave over the roots, or change the soil grade can kill existing trees. Chemical contamination of the soil and poor care will slowly kill even the strongest of trees. Roy Appleton of the Dallas Morning News has recently written an article that discusses some of the issue, it serves as a great primer to some of the underlying concerns:

The area near the old Post Oak was scraped as part of the remediation process and with it went the old Post Oak. Tim Dalbey got word that the tree would be removed from the property entirely in just a couple days so the race was on to get some priceless tree ring “cookies” from the trunk.

The work to remove tree slices first began at the conclusion of a plant survey at Big Spring(results are below, scroll down for an ever growing list). Those attending were able to speak with construction supervisors about removing slices, got the OK and were given word on that Friday that they only had till Monday at dawn to get the tree parts.

The work was supervised by Geo-Marine, the city archeology contractor that coming late Sunday afternoon. The work was started that Friday by Billy Ray Pemberton with his trusty chainsaw.

Followup work that Sunday was completed by Tim Dalbey and Sean Fitzgerald. Sean in addition to being great with a chainsaw is also the very best photographer of the Trinity River, bar none. showcases much of what he sees on the river.

Sean Fitzgerald at Lemmon Lake in his floating blind with Roseate Spoonbills flying over him, July 2012

His stunning images dominate public places around town, in print and on the City of Dallas website. 

Tim Dalbey and Sean Fitzgerald

Tim Dalbey has slices of one other Post Oak tree from this same part of town that date back to when the Beeman family first settled the land in the 1840s. Using a scientific method called dendochronology one can first sand the surface of the slice and painstakingly measure and record each growing year.

Growth rings, also referred to as tree rings or annual rings, can be seen in a horizontal cross section cut through the trunk of a tree. Growth rings are the result of new growth in the vascular cambium, a layer of cells near the bark that is classified as a lateral meristem. This growth in diameter is known as secondary growth. Visible rings result from the change in growth speed through the seasons of the year, thus one ring usually marks the passage of one year in the life of the tree.

Many trees make one growth ring each year, with the newest adjacent to the bark. For the entire period of a tree’s life, a year-by-year record or ring pattern is formed that reflects the climatic conditions in which the tree grew. Adequate moisture and a long growing season result in a wide ring. A drought year may result in a very narrow one. Alternating poor and favorable conditions, such as mid summer droughts, can result in several rings forming in a given year.

Success! A great clean slice from the old Post Oak trunk

Since Dr Dalbey has two sections from different trees of the same species, one interesting idea will be to cross-reference the data. It should tell what the environment, weather, rainfall and growing seasons were like in this part of North Texas going back several centuries. The slices extracted here are near perfect for such work, free from rot and splitting.

I would not hazard a guess to the absolute age or conclusions that will be drawn from the data. Post oaks can often kick out a false ring when a growing season stops and restarts during the same year.

The slices measured 38 inches or so in diameter, almost too large for any conventional chain saw one would have at home.

Bill Pemberton with a tree slice he started on and Sean finished

Two slices in all were extracted. One was taken by Tim for his dendrochronology work, the other was brought over to the Pemberton home where it was given to Mr Billy Ray Pemberton. His family’s slice was sawed by him to a large extent and finished off a couple days later by Sean Fitzgerald.

Very difficult and hard work. So much of it is down here. The reward though is one that few get to experience. Only a handful of folk have ever seen the sunset from the backyard of the Pembertons. A sunset view of many miles to the west. Gotta be a special person to command a sunset audience there. A priceless experience.

The Ongoing Plant Surveys at Big Spring

High School Senior Alexander Neal and Historian MC Toyer discussing the history of Big Spring among the fall wildflowers in the Big Spring pasture, October 2013. Alexander is a student at Townview Magnet and is working on a Senior thesis about preservation and the aspects of the Trinity River Project

The stark contrast of landscapes between the construction next door at the Horse Park and that of the serene Big Spring landscape are readily apparent in the fall of 2013. The late summer and early fall rains have contributed to a new growth of second crop wildflowers in the pasture here that serves as a bio-buffer between the construction and the fragile Big Spring site.

Indian Blanket wildflower growing at the “topographic high” area of the Big Spring meadow. The exact spot where this wildflower is growing is known as 41DL72 a pre-historic Native American site, October 2013

Plant surveys are an important part of understanding the overall environment here. Quarterly surveys have begun here in 2013 which over time hope to catalog the wide and diverse plant and animal life of Big Spring and the surrounding area that will become a future city landmark.

Master Naturalist Jim Varnum, Master Naturalist Jim Flood and Geo-archeologist Dr Tim Dalbey taking notes on a plant species not seen before on previous visits

The plant survey work is led by the local Master Naturalist chapter here in North Texas. The Master Naturalist Program in Texas is a certification process through a Texas Parks and Wildlife program. More information can be found on their website

One of the more well known and whom many regard as the foremost expert Master Naturalist is Jim Varnum. Pictured above in the red checkered shirt. In addition to his near encyclopedic knowledge of plants, he runs one of the best aggregated online newsletters in Texas called Jim’s This and That. A worthwhile link to bookmark as he condenses what is going on around North Texas on a weekly basis. If you ever needed to find something to do in a pinch some weekend outdoors, he always has great suggestions and great insight.

The other Jim, Jim Flood, seen in the middle of the photo, is the trail steward of the Buckeye Trail just across White Rock Creek from Big Spring. His website has contact information about guided hikes and workdays on the Buckeye Trail.

Below is the ever growing and compiled list of flora seen at Big Spring in visits. The list was compiled in spreadsheet format by Jim Varnum. It includes plants through the end of September and number 188 species. An additional 15 new species were documented in mid-October and are not on the list. This list has been previously shared with the City of Dallas office of Trinity River Watershed Management.

Equisetum hyemale subsp. affine Tall scouring rush Hrstls Equisetaceae
Juniperus virginiana Eastern red cedar Tree Cupressaceae
Dicliptera brachiata False mint Forb Acanthaceae
Ruellia humilis Low reullia, Wild petunia Forb Acanthaceae
Ruellia strepens Smooth ruellia Forb Acanthaceae
Acer negundo var. negundo? Box elder Tree Aceraceae -> Sapindaceae
Amaranthus hybridus Green amaranth Forb Amaranthaceae
Amaranthus tuberculatus (PLANTS db) (OLD A. rudis) Water hemp Forb Amaranthaceae
Rhus lanceolata Prairie sumac Tree Anacardiaceae
Toxicodendron radicans subsp. ? Poison ivy All Anacardiaceae
Chaerophyllum tainturieri Chervil Forb Apiaceae
Daucus carota Wild carrot Forb Apiaceae
Hydrocotyle sp. (peltate) ? Pennywort Forb Apiaceae -> Araliaceae
Torilis arvensis Hedge parsley, Beggar’s lice Forb Apiaceae
Ilex decidua Possumhaw holly Tree Aquifoliaceae
Asclepias viridis Green milkweed Forb Asclepiadaceae Apocynaceae
Cynanchum laeve Bluevine Forb Asclepiadaceae Apocynaceae
Matelea gonocarpos Anglepod Vine Asclepiadaceae Apocynaceae
Ambrosia artemisiifolia Little ragweed Forb Asteraceae
Ambrosia psilostachya Western ragweed Forb Asteraceae
Ambrosia trifida var. texana Giant ragweed Forb Asteraceae
Symphyotrichum drummondii var. texanum (OLD Aster drummondii var. texanus) Texas aster Forb Asteraceae
Symphyotrichum ericoides var. = (OLD Aster ericoides) Heath aster (white) Forb Asteraceae
Symphyotrichum lateriflorum var. = ? (OLD Aster lateriflorus) Calico aster Forb Asteraceae
Symphyotrichum divaricatum (OLD Aster subulatus var. ligulatus) Fall aster (white) Forb Asteraceae
Calyptocarpus vialis Straggler daisy, Horseherb Forb Asteraceae
Cirsium altissimum Iowa thistle Forb Asteraceae
Cirsium engelmannii Blackland thistle Forb Asteraceae
Conyza canadensis var. = Horseweed Forb Asteraceae
Dracopis amplexicaulis Clasping-leaf coneflower Forb Asteraceae
Eclipta prostrata Pieplant Forb Asteraceae
Gaillardia pulchella Firewheel, Indian blanket Forb Asteraceae
Amphiachyris dracunculoides (OLD Gutierrezia dracunculoides) Broomweed Forb Asteraceae
Helenium amarum var. = Sneezeweed Forb Asteraceae
Heterotheca subaxillaris Camphor daisy Forb Asteraceae
Iva annua Marsh-elder, Sumpweed Forb Asteraceae
Lactuca serriola Prickly lettuce Forb Asteraceae
Mikania scandens Climbing hemp-weed Vine Asteraceae
Packera tampicana Great plains ragwort Forb Asteraceae
Parthenium hysterophorus False ragweed Forb Asteraceae
Pluchea odorata Camphorweed Forb Asteraceae
Rudbeckia hirta var. pulcherrima Black-eyed susan Forb Asteraceae
Solidago gigantea – tall, lin lvs, glab stem Tall goldenrod Forb Asteraceae
Vernonia baldwinii Western ironweed Forb Asteraceae
Bignonia capreolata Cross-vine Vine Bignoniaceae
Rorippa nasturtium-aquaticum

Lonicera japonica Japanese honeysuckle Vine Caprifoliaceae
Dichondra carolinensis Dichondra Forb Convolvulaceae
Convolvulus arvensis Bindweed Vine Convolvulaceae
Convolvulus equitans Texas bindweed Vine Convolvulaceae
Ipomoea cordatotriloba var. ??? Morning-glory Vine Convolvulaceae
Ipomoea lacunosa White morning-glory Vine Convolvulaceae
Ipomoea wrightii Wright’s morning-glory Vine Convolvulaceae
Melothria pendula Meloncito, Speckled gourd Vine Cucurbitaceae
Acalypha ostryifolia Hop-hornbeam copperleaf Forb Euphorbiaceae
Croton monanthogynus Prairie tea Forb Euphorbiaceae
Poinsettia dentata (OLD Euphorbia dentata) Toothed spurge Forb Euphorbiaceae
Triadica sebifera (OLD Sapium sebiferum) Chinese tallow tree Tree Euphorbiaceae
Tragia ramosa Noseburn Forb Euphorbiaceae
Chamaecrista fasciculata Partridge pea Forb Fabaceae
Desmanthus illinoensis Illinois bundleflower Forb Fabaceae
Desmanthus leptolobus Prairie bundleflower Forb Fabaceae
Desmodium paniculatum Panicled tick trefoil Forb Fabaceae
Gleditsia triacanthos Honey locust Tree Fabaceae
Indigofera miniata var. leptosepala Scarlet pea Forb Fabaceae
Lathyrus hirsutus Singletary Pea Forb Fabaceae
Prosopis glandulosa Honey mesquite Tree Fabaceae
Sesbania herbacea Coffee bean Forb Fabaceae
Quercus macrocarpa Bur oak Tree Fagaceae
Quercus shumardii Shumard red oak Tree Fagaceae
Carya illinoinensis Pecan Tree Juglandaceae
Juglans nigra Black walnut Tree Juglandaceae
Monarda citriodora Lemon mint Forb Lamiaceae
Monarda punctata ssp. = var. intermedia (OLD Monarda punctata var. intermedia) Spotted beebalm Forb Lamiaceae
Teucrium canadense American germander Forb Lamiaceae
Lythrum alataum var. lanceolatum Lance-leaf loosestrife Forb Lythraceae
Callirhoe involucrata var. ? Spreading winecup Forb Malvaceae
Hibiscus laevis Rose-mallow Forb Malvaceae
Modiola caroliniana Carolina modiola Forb Malvaceae
Sida rhombifolia Axocatzin Forb Malvaceae
Melia azedarach China-berry Tree Meliaceae
Cocculus carolinus Carolina snailseed Vine Menispermaceae
Broussonetia papyrifera Paper-mulberry Tree Moraceae
Maclura pomifera Osage orange, Horse apple Tree Moraceae
Morus alba White mulberry Tree Moraceae
Morus rubra Red mulberry Tree Moraceae
Boerhavia diffusa (coccinea) Scarlet spiderling Vine Nyctaginaceae
Forestiera acuminata Swanp-privet Shrub Oleaceae
Fraxinus texensis Texas white ash Tree Oleaceae
Ligustrum japonicum Wax-leaf ligustrum Shrub Oleaceae
Ligustrum quihoui Quihoui’s privet Shrub Oleaceae
Ligustrum sessile fruit

Ligustrum sinense Chinese privet Shrub Oleaceae
Oenothera curtiflora (OLD Gaura mollis (OLD Gaura parviflora)) Lizard-tail gaura Forb Onagraceae
Oenothera suffulta (OLD Gaura suffulta) Kisses Forb Onagraceae
Ludwigia octovalvis Shrubby water-primrose, Narrow-leaf w-p Forb Onagraceae
Ludwigia peploides Water-primrose Aqua Onagraceae
Oenothera rhombipetala Four-point evening-primrose Forb Onagraceae
Oenothera speciosa Showy evening-primrose, Buttercup Forb Onagraceae
Oxalis stricta Oxalis, Yellow wood-sorrel Forb Oxalidaceae
Passiflora incarnata Passion-flower Vine Passifloraceae
Passiflora lutea Yellow passion-flower Vine Passifloraceae
Rivina humilis Pigeon-berry Forb Phytolaccaceae
Polygonum aviculare Prostrate knotweed Forb Polygonaceae
Polygonum hydropiperoides (white) Swamp smartweed Forb Polygonaceae
Polygonum pensylvanicum (pink) Water smartweed Forb Polygonaceae
Rumex crispus Curly dock Forb Polygonaceae
Rumex pulcher Fiddle dock Forb Polygonaceae
Anemone berlandieri Anemone, Windflower Forb Ranunculaceae
Clematis pitcheri Leather-flower Vine Ranunculaceae
Berchemia scandens Rattan-vine Vine Rhamnaceae
Geum canadense var. camporum White avens, Geum Forb Rosaceae
Prunus mexicana Mexican plum Tree Rosaceae
Pyrus calleryana Bradford pear Tree Rosaceae
Rubus trivialis Southern dewberry Forb Rosaceae
Cephalanthus occidentalis Buttonbush Tree Rubiaceae
Diodia virginiana (white) Virginia buttonweed Forb Rubiaceae
Zanthoxylum clava-herculis Hercules’-club, Prickly ash, Toothache tree Tree Rutaceae
Populus deltoides subsp. = Eastern cottonwood Tree Salicaceae
Salix nigra Black willow Tree Salicaceae
Cardiospermum halicacabum Balloon vine Vine Sapindaceae
Sapindus saponaria var. drummondii Western soapberry Tree Sapindaceae
Agalinis heterophylla – pedicel 4 mm Prairie agalinis Forb Scrophulariaceae / Orobanchaceae
Castilleja indivisa Texas paintbrush Forb Scrophulariaceae / Orobanchaceae
Ailanthus altissima Tree-of-heaven Tree Simaroubaceae
Physalis cinerascens Ground-cherry Forb Solanaceae
Physalis turbinata Thicket ground-cherry Forb Solanaceae
Solanum dimidiatum Horse-nettle Forb Solanaceae
Solanum elaeagnifolium Sliver-leaf nightshade, Trompillo Forb Solanaceae
Solanum rostratum Buffalo bur Forb Solanaceae
Celtis laevigata var. = Hackberry, Sugarberry Tree Ulmaceae -> Cannabaceae
Ulmus americana American elm Tree Ulmaceae
Ulmus crassifolia Cedar elm Tree Ulmaceae
Boehmeria cylindrica Small-spike false-nettle Forb Urticaceae
Callicarpa americana American beauty-berry Shrub Verbenaceae
Glandularia bipinnatifida Prairie verbena Forb Verbenaceae
Lantana urticoides Texas lantana Shrub Verbenaceae
Phyla lanceolata (OLD Lippia lanceolata) Lance-leaf frogfruit Forb Verbenaceae
Phyla nodiflora (OLD Lippia nodiflora) Texas frog-fruit Forb Verbenaceae
Verbena brasiliensis Brazilian verbena Forb Verbenaceae
Verbena halei Texas vervain Forb Verbenaceae
Viola missouriensis Missouri violet Forb Violaceae
Phoradendron tomentosum Mistletoe Para Viscaceae
Ampelopsis arborea Peppervine Vine Vitaceae
Ampelopsis cordata Heart-leaf ampelopsis Vine Vitaceae
Cissus trifoliata (OLD Cissus incisa) Cowitch Vine Vitaceae
Parthenocissus quinquefolia Virginia creeper Vine Vitaceae
Vitis cinerea var. = Summer grape, Swet grape Vine Vitaceae
Vitis mustangensis Mustang grape Vine Vitaceae
Tribulus terrestris Goat-head (yellow) Forb Zygophyllaceae
Sagittaria graminea Grassy arrowhead Mom Alismataceae
Sagittaria latifolia Common arrowhead Mono Alismataceae
Sagittaria platyphylla Delta arrowhead Mono Alismataceae
Commelina erecta var. = Dayflower Mono Commelinaceae
Carex sp. thin, light green leaves Mono Cyperaceae
Carex sp. broader, dark leaves Mono Cyperaceae
Carex cherokeensis Cherokee caric sedge Sedge Cyperaceae
Carex crus-corvi Crow-foot caric sedge Sedge Cyperaceae
Cyperus erythrorhizos (red roots) (BO) Red-root flat-sedge Sedge Cyperaceae
Cyperus retroflexus One-flower flat-sedge Sedge Cyperaceae
Cyperis sp.

Iris sp. Flag Mono Iridaceae
Lemna sp. ? duckweed Mono Lemnaceae -> Araceae
Juncus torreyi Torrey’s rush Mono Juncaceae
Zephyranthes chlorosolen (former Cooperia drummondii) Rain lily Mono Liliaceae -> Amaryllidaceae
Aegilops cylindrica Jointed goat grass Grass Poaceae
Bothriochloa ischaemum var. songarica King Ranch bluestem Grass Poaceae
Bothriochloa laguroides subsp. torreyana Silver bluestem Grass Poaceae
Cenchrus spinifex Sand-bur Grass Poaceae
Coelorachis cylindrica Carolina joint-tail Grass Poaceae
Cynodon dactylon Bermuda grass Grass Poaceae
Dactylis glomerata Orchard grass Grass Poaceae
Echinochloa sp.
Grass Poaceae
Echinochloa muricata var. = a barnyard grass, NCN Grass Poaceae
Elymus canadensis Canada wildrye Grass Poaceae
Elymus virginicus Virginia wildrye Grass Poaceae
Panicum virgatum Switchgrass Grass Poaceae
Paspalum notatum var. latiflorum Bahia grass Grass Poaceae
Paspalum dilitatum Dallis grass Grass Poaceae
Polypogon monspeliensis Rabbitfoot grass Grass Poaceae
Phalaris caroliniana Carolina canarygrass Grass Poaceae
Setaria parviflora Knot-root bristlegrass Grass Poaceae
Sorghastrum nutans Yellow Indian grass Grass Poaceae
Sorghum halepense Johnson grass Grass Poaceae
Tridens flavus Purpletop Grass Poaceae
Potamogeton nodosus Long-leaf pondweed Aqua Potamogetonaceae
Smilax bona-nox Catbrier Vine Smilacaceae
Typha domingensis Narrow-leaf cat-tail Aqua Typhaceae