The Final Sorting

Well over a hundred harvester ant colony mounds were explored and the data used to demonstrate that harvester ant colony densities were a function of grazing intensity on the landscape around the Painted Pony Resort.  Finally, all the small crystals collected from the mounds were sorted.  Quartz, in the form of Chalcedony as well as small quartz crystals (6 sided) were noted in the samples as well as other crystal morphologies, such as cubic and octahedral crystals.  The first image below was taken with a digital microscope and shows the variety of crystalline forms found around the harvester ant colonies.  The next 2 photomicrographs show some of the octahedral crystalline morphologies found during the sorting process.  By examining about 100 colonies within about 1 square mile and estimating the amount of soil sampled by the ants at 50 cubic feet (based on measurements from an exposed ant nest), about 5000 cubic feet of soil was sampled in looking for crystals.  No more than about 20 grams of crystals were recovered and of those only 3 showed clear octagonal crystalline structure.  Not a very good yield and lots of work for very little return, but the utility of harvester ants as an indicator species made the effort worthwhile.

While some may have heard the story of the great diamond hoax of 1872 all these stones were collected from around the estate, but one has to be willing to kneel in active harvester ant colonies to collect these tiny crystals.  You can find almost anything in the boot heel of New Mexico, if you have eyes to see.

harvester ant mound crystal specimens
A photomicrograph of clear crystals from harvester ant colony mounds.

Octahedral crystals.

Octahedral crystals from harvester ant nest mounds.


More Gifts From the Ants.

While testing the idea of harvester ants as a rangeland health monitor species, small crystals from the ant colony mounds were collected and sorted.  Below are small (~3 mm) specimens of chalcedony found outside colony entrances.  The image was taken using a digital dissecting microscope.  While the second image is the same grouping but photographed under UV light with a camera.  Note several of the chalcedony pieces fluoresce with a greenish light.  This behavior was also noticed in larger chalcedony specimens collected from the high New Mexican desert around the Painted Pony Resort.

Chalcedony specimens collected from the mounds surrounding harvester ant colonies.
The same grouping of chalcedony but under UV light.


Harvester Ants as a Rangeland Indicator Species

Ants, especially harvester ants utilize seeds as a food source and might be a useful indicator species for the grassland restoration efforts at the Painted Pony Resort.  A number of reports suggest that both soil composition and grazing intensity can alter harvester ant colony frequency on the landscape (1, 2, 3). Variation in ant colony density across the estate was noted while preparing a previous post on indicator minerals in ant colony mounds so a small comparative study was designed to test the hypothesis that harvester ant colonies varied with the grazing intensity on the estate.  A 3 km transect across the estate from west to east, starting on grazed New Mexico State land was chosen and at 14 stations a 30 m diameter circle (area = 730 meters2) was examined for harvester ant colony entrances.  A colony was defined on the basis of a circular pile of small (1-2 mm) stones, and an entrance hole with or without harvester ants on the surface. Although other ant species were observed along the transect these were not included in the colony totals.
Constantly grazed land had a average of 1 colony/730 m2 while ungrazed land averaged 4 colonies/730 m2 and there was a significant difference in the frequency of harvester ant colonies between the 2 grazing regimes, P = 0.003, single tailed t-test.  Since soil type also varies across the estate the number of colonies by soil type was also tested. Forest-Pinleno association is found on the west side of the estate while Eba very gravelly loam predominates the eastern portion of the estate. There was no significant difference in harvester ant colony density between these 2 soil types, P = 0.12, single tailed t-test. This suggests that soil composition, and secondarily plant species diversity, are not a major contributor to harvester ant colony frequencies on the estate in the semi-arid southwest, but rather the frequency of grazing (constantly grazed versus ungrazed land) is the more important determinant of harvester ant colony frequency in and around the estate.

Satellite view of the 756 acre Painted Pony Resort showing 3 km transect and locations of test sites.  The red line indicates the property boundary but no fencing and accessible to cattle, while the white line indicates fencing around the estate where cattle are excluded.  The 3 stations furthest west lie on New Mexico State land which is grazed year round.

Frequency of harvester ant nest colonies.

Soil map of the Painted Pony Resort.


Lunar Eclipse: Rained out in Southern New Mexico

All prepared for the big lunar eclipse but it was rained out.  The Painted Pony Resort received 0.21" from this late monsoon storm and it made viewing the event impossible.  I did manage a photograph just at moon rise as the full moon rose just over the mimetolith (stone face profile) in the Peloncillo mountains just south of Antelope pass in southern New Mexico.  Visible from the estate, this large stone face profile appears to be watching the full moon rise over awaiting the eclipse.  I felt very fortunate to walk outside just at the right time on an evening when the moon was full and positioned over the mimetolith, it was just the right combination of factors to get a unique image.

Looking at the Moon


Indicator Minerals and the Gift of the Ants

While ants are considered pests by many, their biology is of interest to many entomologists. In the desert southwest the Harvester ants of the genus Pogonomyrmex are a common occurrence on the landscape.  In fact at the American Museum of Natural History Southwest Research Station a yearly course on southwestern ants is taught.  Harvester ants nests are easily found since they occupy large open areas which the ants clear of plant material and the entrance mounds may be over a foot tall looking like small volcanic cones.  The detritus that makes up the mounds is a combination of excavated material from chambers in the colony, plant refuse, and other organic material.  Harvester ants colonies essentially sample the soil while building chambers within their nests by removing small gravel and dirt which is conveniently placed just outside the entrance for inspection.  The volume of soil sampled is a function of nest size and in the images below a profile of an abandoned nest over 4 ft in depth and 2 feet across resulted in a sampling of 50 cubic feet of soil.  These naturally produced soil samples are used by geologists in explorations for commercially important minerals and in Australia, ant nest mounds are explored to locate gold deposits.  Recent explorations of harvester ant nest mounds at the Painted Pony Resort did not identify any specific mineral deposits but did uncover some interesting crystals.  While small in size and not very common in nest mounds the crystals are quite beautiful with some interesting crystal structures. 

In the process of looking for nest mounds there seemed to be variation in the frequency of harvester ants colonies across the landscape and this may be related to landscape quality.  Areas to the east with little ground cover seemed to have fewer ant colonies while on the western side of the San Simon riverbed, where grazing is excluded, there seemed to be more colonies.  This observation suggests that harvester ants may be useful a proxy indicator species for range land health and an experiment to test this idea is under development. 

The surface expression of a large mature Harvester ant colony.  The mound of excavated material is over 1 ft in height.

Underground expression of an ant colony.  Four foot deep and approximately 2' wide this nest sampled approximately 50 cubic ft of soil.

Ant nest, closeup of underground chambers.  Note the connections between chambers.
clear crystals from nest mounds.

More clear crystals from harvester ant colony mounds.  The rounded specimen in the bottom left is chalcedony which is weakly fluorescent.


Tumbleweed Cannoli

Cannoli are great Italian desserts with a fried pastry shell stuffed full of yummy filling but down in the bootheel of New Mexico there are not available, so we make do without.  In terms of landscape restoration though, the idea of a cannoli translates to another use for tumbleweed.  Tumbleweed is used in garlands on the Painted Pony Resort for arroyo stabilization and has been adapted for use in topsoil restoration barriers.  One of the problems with using annual grasses in topsoil barriers is their light weight.  With a wind storm the grasses become dislodged and move reducing the efficiency of the barrier.  But by wrapping the annual grasses, Amaranth and other weeds in a shell of tumbleweed the mass is heavier and stays put.  The natural stickiness of tumbleweed stems makes them ideal for wrapping the lighter grasses and weeds.   Below are 3 photographs of the process used to create tumbleweed cannoli.  Flattened tumbleweed is filled with annual grasses and then rolled allowing the tumbleweed shell to hold to itself.  The finished cannoli is then placed on the landscape as a barrier to catch sediment and create microhabitat for new grasses the next year.  It is similar in design to using rolled hay barriers but costs nothing in materials since everything is off the landscape.  Another example of using products of the land to heal the land and restore the landscape.

Flattened tumbleweed as the cannoli shell.

Annual grasses and amaranth as the cannoli filling.

A 5' long rolled tumbleweed cannoli ready for placement.


Rangeland Restoration: Mesquite Removal

While mesquite removal continues in the river bed in an effort to restore the area to open grasslands, mesquite removal began on the upper benches around the main complex of buildings at the Painted Pony Resort.  Because of deep taproots, mesquite is difficult to remove and experiments using the tractor required a second treatment with herbicide to completely kill the plant.  The Galion Grader, on the other hand, weighs 35,000 lbs and easily pulls the mesquite, taproot and all, out of the ground.  So after some modification to protect the hydraulic hoses, the machine was used to grub mesquite off the benches above the river bed.  Between 30 and 40 acres of mesquite were removed with the grader by the owner of the estate over a day of work.  The front tines were lowered and used to grab each plant and as the machine was moved forward the big diesel engine would provide enough power to pop most intermediate sized mesquites out of the ground.  So piles of uprooted mesquite dot the landscape at the moment but the material is being redistributed along the contours of the land to create additional topsoil barriers.  This spreads out the plant material allowing more rapid decomposition the creation of micro-habitat for the catchment of wind and rain blown seed and soil which will in turn provide new grass the opportunity to grow and spread over time.  With the establishment of new grass the tumble weed problem will slowly resolve itself since perennial grass cover will out compete the yearly tumble weed crop.

Intermediate sized mesquite with tap root and stringer roots.

Topsoil barrier created from grubbed mesquite.


Tabosa Grass, the Grassland Indicator Species

The Painted Pony Resort's grassland restoration project is aimed at restoring the native grasslands once so common through out New Mexico and the southwest.  In the segment of the San Simon riverbed on the estate the major grass species is Tabosa,  Pleuraphis mutica. This drought tolerant grass species is a major component of the grasslands and as restoration work proceeds this species is a useful qualitative indicator species of the restoration process.

Slowly new Tabosa grass is moving up out of the riverbed and back onto the landscape where grazers are excluded.  Below is a photograph from the riverbed showing complete ground coverage while the next image is from a bench above the riverbed where  grasses are being recovered.  The presence of new stands of Tabosa grass indicate that the seed reservoir concept is producing results.  While the topsoil restoration barriers have produced annual grasses during their first year, the eventual presence of the perennial Tabosa grass along the barriers will mark the next step in the restoration process and a shift from annuals to perennial grasses.

Tabosa grass in the San Simon riverbed (the seed reservoir)

Tabosa grass on the upland benches


Odile's Gift to the Twin Cities of Portal Rodeo

Hurricane Odile arrived from the Pacific after moving across northern Mexico and southern Arizona.  Its' arrival began as a slow march of cloud cover up the San Simon valley and over the mountains.  The resulting sunset was a multicolored event that belied the amount of rain that was to fall.  The first 2 days of rain were light at the Painted Pony Resort where a modest 0.11" and 0.26" of rain were recorded.  Then the main mass of the storm arrived bringing significant amounts of rainfall to the area with reported 1 day totals between 4 - 5 inches of rain around the valley.  Cave Creek Canyon experienced serious flooding as did areas of the valley including highway 80.  The main mass of the storm delivered 3.34" of rain to the estate over a 24 hr period and then began to taper off with a final days total of 0.41".  The total accumulated rainfall for the storm on the estate was 4.17" bringing the yearly reported total for station NM-HD-17 to 12.54".

As shown in the images below, water flow across the landscape (flooding) was confined to 2 areas where an old drainage from the west crosses the estate on its way to the San Simon river bed.  Experiencing mostly sheet flooding water depth reached a maximum depth of 1-2', although wide swaths of the road were flooded.  Of course the riverbed itself as conduit for water from up the valley (to the south) had several feet of water and the east side of the estate is currently inaccessible.  The check dams, tumbleweed garlands, and topsoil restoration barriers preformed well and all were in place after the storm.  Capturing sediment and slowing water flow these structures protected segments of the road and barren areas of the landscape slowing the water and depositing sediment.  One problem arroyo along Painted Pony Rd. collected about a foot of sediment during the storm demonstrating the efficacy of water management efforts on the estate.

The arrival of Odile was heralded by a multicolored sunset over the San Simon valley.
After the big rain - looking west at the flow across Nighthawk Rd.

After the big rain - looking south at the flow across Painted Pony Rd.
After the big rain - an old drainage that has good grass cover.

After the big rain - a check dam with tumbleweed garland and newly collected sediment along Painted Pony Road.
After the big rain - performance of topsoil restoration barrier installed last year.


Rangeland Rehabilitation: Stabilizing Arroyos

Arroyos in the desert southwest are major conduits of water across the landscape and during the rainy seasons can be major sources of erosion on a lightly vegetated landscape.  On the 756 acres of the Painted Pony Resort just several arroyos contribute to the majority of erosional damage on the estate.  These arroyos collect water from the west flanks of the Peloncillo mountains which is concentrated into 3 arroyos by bridges along the old El Paso and Southwestern Railroad running along the base of the mountains.  The water collected on the up slope side of the railroad bed is funneled through the bridges and across the property down these 3 arroyos eventually reaching the San Simon Riverbed.  The concentrated and rapidly flowing water erodes both down through the soils and also moves the arroyos laterally.  The high velocity water makes roads on the east side of the estate impassible and washes out culverts and crossings which require significant repair work.  While the changes in drainage patterns as a result of the railroad bridges is beyond one persons ability to easily change, the arroyos resulting from a century of landscape modification can be managed to reduce the damage caused by concentrated high velocity water.  

One of several arroyo management techniques in use requires stabilization of the arroyo banks.  Over 10' deep in places on the estate, arroyo banks frequently collapse and stabilization would reduce the amount of soil eroded during the rains.  But what sort of stabilization technique is applicable?  Being in favor of utilizing low cost materials that are available on the landscape this is the approach most frequently chosen.  Many times people toss in whatever garbage is available into arroyos to slow water flow and protect the banks, but this approach results in an arroyo strewn with leftover wood and metal products which randomly catch sediment and is unsightly (the out of sight out of mind approach).  An alternative approach is to utilize plants for stabilization.  In this case, a native species of ground spreading gourd Cucurbita sp.. 

Members of this genus are low growing ground covering annuals and perennials, in many species the fruit is edible and include cultivars of squash and pumpkin.  Adapted to arid climates and growing well in sandy soils they can be found along roadsides and the gourds may be collected in the late summer.  Producing about 300 seeds/gourd, 3 species of Cucurbita are found on the estate, Cucurbita digitata , Cucurbita foetidissima, and an unidentified species.  The green developing gourds turn yellow when dried and are easily spotted on the landscape for collection.  Arroyo stabilization requires harvesting the gourds and extracting the seeds which are then planted high along the edges of arroyos.  The gourd produces a taproot allowing it anchor itself deeply in soil ensuring it will not wash out with periodic high water and hold the soil.  The long vines it produces cover the ground, absorbing energy and slowing water, and will hang along vertical surfaces allowing its large leaves to protect the underlying soil, reducing soil loss.

Previous tests with planted Cucurbita along the entrance driveway resulted in plant coverage over areas of barren ground which has allowed additional grass to establish itself.  So this is being expanded to treat problem arroyos on the estate.  Collected seeds were planted at about 50 locations along a segments of 2 deep arroyos at the bottom to the top at a depth of 1-2".  Starting at the old bridge, quarter sections of gourds were cut and planted along the banks for a distance of several hundred feet.  Next years crop of gourds should spread downstream with the goal of creating more plants that will stabilize these problem arroyos.

Fruit from C. digitata, C. foetidissima, and an unknown species harvested from the estate.
Looking downstream along a problem arroyo, treated by planting native gourds .

Looking upstream at an old El Paso and Southwestern railroad bridge that funnels water creating problem arroyos.

Native Cucurbita along an arroyo showing how the vines and leaves provide cover for developing grasses.



As a result of 5+ inches of rain in one month (August) the weeds have gone to town.  I hand pull most weeds so I have material for the topsoil restoration barriers but this is getting ridiculous.

This area around the bungalow, inside and outside the wall, was weeded numerous times this summer.  Three times for tumbleweed and other volunteers, and now for the annual finger grass that mysteriously grew after the last herbicide treatment.  Fortunately, finger grass is an annual and will die on its own after seeding and it is easy to pull, so I'll be spending the rest of the day pulling grass.

Partially cleared Finger grass, an annual grass growing around the bungalow.

cleared of weeds.


Chiricahua Peloncillo Heritage Days 2014

Another great community event this weekend.  The Chiricahua Peloncillo Heritage Days are a yearly event sponsored by local interests to celebrate the natural and cultural heritage of the area.  Starting Friday evening with a reception and keynote address by a climate scientist from Tucson.  Saturday was filled with talks ranging from C.S. Fly to soil mapping in Arizona and New Mexico and a special kids area with activities was hosted by local educators.  Lunch was catered by the Rodeo Tavern with tasty southwestern style chicken fajitas and eggplant casserole.  The rain held off, though we were hoping, and Sundays scheduled walk at Faraway ranch and the wildflower walk up Cave Creek had nice cool temperatures.  This year marked support for the event by Hidalgo county lodgers tax, as well as other local businesses, which means the event is becoming self sustaining.  This bodes well for future Heritage days and I certainly look forward to the event every year.

The craft and farmers market.

Waiting for the talks to begin.

Friends of Cave Creek Canyon display board.

Speakers and presentations.