More Horse, of Course

With the arrival of the monsoon more bone has come to light.  The small arroyo where the teeth were originally found produced another bone.  Tentatively identified as a calcaneus bone,  it was discovered about 4' from the pelvis.  It is still unclear whether the animal was dis-articulated after death (either by scavengers or humans) or whether the animal was initially intact but poor preservation conditions resulted fragmentary fossilization.  This question will have to wait until more evidence is uncovered, but a map of artifacts found on the surface surrounding the location currently do not give any indication of obvious relationships.  In spite of the fragmentary evidence, the location of the teeth (especially those with fresh breaks), the pelvis, and now a calcaneus suggests the animal was on its right side with the head toward the road when it was covered and the preservation process began.

An in situ fossilized calcaneus bone from a horse.

Location of calcaneus relative to the presumptive pelvis.

Marrow cavity and spongy bone is visible in the cross section of the calcaneus.

Google map showing distribution of surface artifacts noted around the horse.

Rangeland Rehabilitation: In Defense of Weeds

Weeds, the ubiquitous unwanted plants.  Their characteristics such as rapid growth and spread, combined with their ability to colonize disturbed environments make them the bane of many land owners.  But there is an upside to weeds, especially if working to rehabilitate former rangeland such as the grassland restoration project at the Painted Pony Resort.  Local Plamer's pigweed or Amaranthus palmeri grows on the estate and particularly likes the lowest sections of the river bottom where it can be found in large swaths during the monsoon season.  Native to the southwest and edible, its' ability to quickly convert soil nutrients into biomass results in rapid growth and combined with the ability to sequester excess nitrogen makes it ideal for topsoil barriers construction (no additional fertilizer required).  Since pigweed may be toxic to cattle because of the nitrates in the leaves, it is an undesirable species in the restored grasslands of the riverbed so an alternate use for this plant was sought.  The previous years test barrier experiments with local pigweed resulted in new grass along the test barriers (see last image), so this was expanded to include additional areas on the estate.  Pigweed in the river bottom was harvested with the rake on the tractor.  The material was then transported up onto the benches along the riverbed and distributed in rows perpendicular to the dip (parallel to the San Simon riverbed) allowing the biomass to collect wind and waterborne sediment and additional seeds.  This micro-habitat will in turn support new grass next season.  The new grass will continue to slow water on the landscape allowing time for more water to soak into the ground which will in turn support more grass, creating a cycle which will eventually rebuild topsoil and return the landscape into desirable grasslands.  So what is considered a nuisance by some has an important use on the estate and is one more way to use what the land produces to help restore other areas.

Collecting Amaranthus palmeri from the San Simon riverbed

Clearing pigweed in the river bottom

Several hundred feet of topsoil restoration barrier in place.

A pigweed barrier from last year with new grass on barren soil.

Like a Kid in a Candy Store

As a biologist I have always had access to a microscope, whether in school or operating a lab, a microscope has always been an integral part of being a biologist.  But for the past several years I have not had access to a microscope.  A good compound microscope is expensive and all I really needed was a dissecting microscope but even those can be expensive.  A local dissecting microscope became available but tires for the vehicle had priority and ate up all the savings.  So I had been looking online at available microscopes.  Noticing that a variety of USB digital microscopes were available I began looking at them as opposed to a traditional dissecting microscope.  While most available digital microscopes have either no stand or a poorly designed stand, one manufacturer has included a solid stand to hold it's digital microscope, a must for steady closeup work.  Celestron, a telescope manufacturer, has a series of digital microscopes which come with adjustable stands.  I chose the 5 MP digital microscope based on the potential resolution and the adjustable stand.  With both course and fine focusing this digital microscope may also be calibrated for measuring objects.  Easy to setup and use, it will be a useful addition to my tool box allowing exploration of the 756 acre Painted Pony Resort at a much smaller scale.  Below are a few images made while testing the new instrument.

Celestron digital USB microscope

Secondary flaking along the edge of a burin.

Tentatively identified as a Longhorn beetle, tribe Lepturini .

Cut surface of an interesting magnetic rock from the estate under study.

Range Restoration: Building Topsoil

The Painted Pony Resort lies in San Simon Valley between the Chiricahua Mountains and Peloncillo Mountains of southwestern New Mexico just a couple of miles from the Arizona boarder which bisects the valley.  An open valley set between towering mountains ranges a variety of people have called it home.  From early hunter gather groups to early agricultural groups such as the Mimbres and Hohokam and up to the present the valley has seen it all, from hunting to farming and most recently grazing.

Past range management decisions, beginning in the late 1800's with corporate ranching combined with changes in rainfall have resulted in a generally altered rangeland in many areas of the valley.  A decrease in grasses combined with an increase in woody shrubs, notably mesquite and creosote, have reduced the current productivity of the landscape.  A local attempt to restore and sustain the grasslands is spearheaded by the Malpai Borderlands group whose goal "is to restore and maintain the natural processes that create and protect a healthy, unfragmented landscape to support a diverse, flourishing community of human, plant and animal life in our borderlands region."  Through their efforts much of the bootheel is managed for both cattle and wildlife.  Yet there are other areas (notably public lands, state and federal) where management practices are not producing an increasingly productive landscape but rather a continuing decrease in productivity is observed (see image below).  One of the goals at the Painted Pony Resort is to increase range land productivity on the estate through the grasslands restoration project.

The estate is composed of 750 deeded acres spanning the both sides of the San Simon Riverbed, it includes 6 types of soil, and last year received about 10.75" of rain (CoCoRaHS rain network, NM-HD-17).  The ground cover varies significantly across the estate and ranges from areas denuded of grasses where erosion has eliminated the topsoil to other areas such as the riverbed where fencing has created a seed reservoir used for spreading native grass seed back onto the surrounding landscape.  After successful preliminary experiments with simple top soil restoration barriers as a tool to slow erosion and encourage new grasses these barriers were expanded in both scope and materials.  Instead of simple barriers constructed from cut weeds, mesquite from the riverbed was employed to create topsoil restoration barriers.  Mechanically removed mesquite is transported up out of the riverbed and placed in rows perpendicular to either the dip or to the prevailing winds on a scarified subsoil base.  Grass from the riverbed is then harvested and placed on the upwind (up dip) side of the mesquite barrier followed by some soil from the riverbed to reintroduce microbes and nematodes crucial to developing new topsoil.  The branches of the mesquite combined with raked grasses create micro climates on the exposed subsoil leading to new plant growth.

The result of this effort is already producing results.  As shown below the mesquite topsoil barriers have caught wind blown seed, slowed water flow and new grasses are developing along the restoration barriers.  A simple technique that can be implemented by anyone, the topsoil restoration barriers are useful tools for building new topsoil and restoring the landscape and best of all require no investment beyond time and energy.

Blowing dust on New Mexico State land, the result of poor range management decisions.

Soil map showing the boundaries of the Painted Pony Resort.

Three topsoil restoration barriers installed on the exposed subsoil, click to enlarge.

New grass along a mesquite topsoil barrier

New grass along a topsoil barrier

A topsoil restoration barrier with new grass created from road waste.

Louisiana State Arthropod Museum (LSAM) Returns

The Louisiana State Arthropod Museum returned this month for another visit.  Students and museum staff make the yearly trip and upon their arrival at the Painted Pony Resort is transformed into a field station for the duration of their visit.  Collecting equipment is unloaded, processing stations created in the garage, and microscope stations set up in the computer room.  After dinner and an evening introductory lecture on the high desert of New Mexico everyone relaxes in the hot tub or heated pool after the long drive then begin preparations for collecting projects.  The days are filled with collecting at various locations from the valley floor up to elevations over 9000' in the high country.  While a series of flight intercept traps are set up around the mountain range to sample the local insect populations.  Favorite collecting locations are visited and repeat samples collected.  Each evening students and staff return and a communal dinner is prepared.  Every day a different person is responsible for preparing dinner for the group which creates a series of international meals since students and staff come from around the world to study at the museum.  After dinner samples are processed and then the group relaxes with a movie, more swimming, and black light stations set up around the estate are monitored.  Of course with 750 acres the Painted Pony Resort and adjoining public lands are also used for collecting and students could be found out on the landscape with nets throughout their visit.

Here are several images by Mike Ferro of LSAMs 2014 visit to the Painted Pony Resort.  Additional images from the 2014 LSAM collecting trip may be found at:
https://www.flickr.com/photos/12666884@N00/sets
https://www.flickr.com/photos/98218272@N05/14669413607/
https://plus.google.com/photos/108279953306115325580/albums/6047139897560460737?banner=pwa

The first evenings lecture

The arrival and unloading

Collecting in the high desert

Collecting at the light trap

Processing samples in the garage

Microscope station in the computer room

Relaxing after a day of field work

Collecting from an ephemeral pool next to the estate

2014 Monsoon Season in Southwestern New Mexico

The monsoon season is well underway and the mountains on both sides of the San Simon valley are receiving good rains.  But out in the middle of the valley it is a little slower.  The Painted Pony Resort has received about 6" so far this year and hoping for more.  Yesterdays rain was heavy in both the Peloncillos and Chiricahuas but we received only 0.07".  This morning though the views were nice and I took some time from cleaning to capture the image below.  Desaturated, the image is just one of the many faces of the Chiricahua mountains, always changing with the light and seasons.  Always something new to see.

The 8000' Portal Peak on the east side of the Chiricahua mountains

Mesquite Treatment and Rangeland Restoration

One of the goals of the grassland restoration project is to return the segment of the San Simon riverbed at the Painted Pony Resort to open grassland, creating a seed reservoir, and this means removing mesquite.  The riverbed was over run with mesquite as a result of unmanaged cattle grazing.  Cattle are a major dispersal agent in the spread of mesquite, eating and passing seeds back onto the landscape where they germinate.  Originally confined to riparian areas, mesquite has spread across the landscape in modern times.  But it is not all bad, mesquite provide forage for cattle and other native browsers, habitat for nesting birds, and most importantly they fix nitrogen in addition to holding the soil.  Mesquite can be stubborn to remove since they produce deep tap roots and mechanically removed mesquite come back quickly requiring further treatment.  A backhoe or other device that will pull the taproot out is required to completely remove the plant and prevent regrowth.  Alternatively, herbicide treatment may be used after initial removal of the above ground portions of the plant.  But tests by others with a number of different herbicides show variable results with both application timing and herbicide compound being important variables.  Because of the variable results with different herbicides a 2 prong approach was chosen for herbicide treatment.  Glyphosate (the active chemical compound found in Roundup) is available off label at 40% concentration.   This is diluted to a final concentration of 2% (found in commercially available formulations) and combined with 2,4-D at a final concentration of 0.2%.  2,4-D is a plant hormone analogue while Glyphosate interrupts amino acid synthesis.  Once absorbed both herbicides work through different mechanisms interrupting plant growth and killing the reoccurring mesquite.  Below are photographs of a mechanically removed mesquite in the riverbed treated with this combination of herbicides.  Although effective some regrowth is noted requiring a second application to finish off the mesquite.

This combination of mechanical removal followed by herbicide treatment is returning the riverbed to an open grassland while maintaining a few large single stemmed mesquites for habitat and leaving mesquite along the margins and on the uplands to provide cover, soil stabilization, and nitrogen fixation this approach shows what may be accomplished with a minimal investment.  

Untreated, 2 weeks after mechanical removal

96 hrs post herbicide treatment

10 days post herbicide treatment, residual new growth will require a second treatment

An Unusual Tool

While out walking the other day with one of the LSU Arthopod Museum's staff the tool shown below was found amongst a scatter of mano fragments.  Downstream of several room shaped crop marks, the presence of flaking and grinding stone tool fragments suggests we were close to a former habitation site.

The oddly shaped piece measuring 3.3 x 6.5 cm was constructed out of a fine grained local red rhyolite common to the area.  Four long primary flakes running the length were removed from one side to create the tool from a single larger flake.  Several very small secondary flakes were removed from the inner curved surface creating a partially serrated cutting edge.  The shape and curvature of the tool suggests right handed usage and when held the thumb fits comfortably in the basal depression at the base while the index finger comfortable wraps around a groove on the backside.

Tentatively identified as either a burin or awl, this unusually shaped tool would be a handy addition to any early tool kit and would work well in either punching holes in leather or cutting and scraping wood or bone shafts.

An oddly shaped rhyolite awl or burin

The back of the tool showing natural finger groove

Addendum:

The tool fits neatly into the right hand.

New Mexico Rangeland Restoration

The grassland restoration project at the Painted Pony Resort continues to bear fruit.  In many areas the topsoil is completely removed due to poor range management techniques in the past and as a result large swaths of landscape are completely barren of vegetation leading to additional erosion problems.

These eroded areas are generally surrounded by terracettes, individual plants or low woody shrubs which hold topsoil and sit up to 18" above the surrounding subsoil.  While observing these naturally occurring terracettes and noting how the plants hold the topsoil an artificial terracette was found.  This artificial terracette was the result of several pieces of hog fence left laying on the ground.  The mesh work held the top soil, creating a micro habitat for new plant growth.  The plants and mesh work would also catch additional windblown seeds and soils continuing the process of topsoil regeneration.  In an attempt to replicate this process an experiment in topsoil restoration was started.  The first treatment utilized weeds pulled around the estate and this material was laid in widely spaced rows perpendicular to the dip, to catch water, or if the ground was level, perpendicular to the prevailing winds.  With the arrival of the monsoons new grass has sprouted along these test barriers and additional soil has accumulated.  The placement of biological material in rows on the landscape creates not only a micro habitat for new plant growth but also slows water running across the landscape decreasing soil loss and in combination with the seed reservoir will help heal the landscape naturally and continue to restore the landscape to its' original condition.

Untreated state land showing soil movement and little grass.

An artificial terracette of hog fencing.

Black lines denote new growth along test topsoil barriers.

A close up of new grass growth along one topsoil test barrier.  Note the accumulation of soil around the line of grass.

A Most Polite Visitor

All curled up in a shallow depression I never saw the Mojave, his light green and brown coloration blended in with the rock and soil covering the ground in the front garden. I had been weeding and was now busy examining an Ocotillo, looking for ways to weave the long stems into something interesting and my mind was elsewhere. Never hearing a rattle the beautifully marked Mojave remained quiet and in an uncharacteristic fashion did not alert me to his presence. Without noticing I stepped over him and continued to look up at the Ocotillo stems trying to divine some some way to train the stems into something interesting. After weaving several stems together I glanced down and saw the Mojave between my feet. Reacting to the presence of a venomous creature between my feet I gave a yelp raised one foot and comically hoped back like some cartoon character. All the time the Mojave just sat there unimpressed and unresponsive. So I retrieved the snake tongs along with a 5 gallon bucket and caught the 18” specimen for relocation. After carrying him about a mile and half away he was released into a low mesquite bush to find a new home off the estate.

I make it a habit to speak with guests about the presence of venomous creatures found in the high desert of New Mexico and if they should see one, to come and find me and the animal will be captured and relocated. The current group of Biologists were of course interested in seeing the specimen and those students on their first trip to the Chiricahua's got their first introduction to some of the wildlife found in the area.

Signage about wildlife in the high desert

A most polite visitor.  Photograph by Michael L. Ferro