October 21, 2023

I do not always go behind our outbuilding when I mow.  The view of the area is blocked by the building and the trees that are on either side.  The area of only about 600 feet² (56 m²) and much of it is covered with the dead needles of the large Loblolly Pine (Pinus taeda) on one side of the building.  When I do go back to mow, I often find interesting things happening.  Several years ago, I wrote about how a large portion of the area was covered with mock strawberries (Duchesnea indica).  While the mock fruit is similar in appearance to wild strawberry (Fragaria vesca) it is not edible, although the plant itself has been used medicinally as an antiseptic, an anticoagulant, and in a poultice for boils and burns.  The next year the gardener from the church that abuts our yard knocked on our door to say the large American elm (Ulmus americana) had blown down in the wind and was lying on their property.  He asked if I would allow his friend to cut it up for firewood.  I did allow it, or else I would have had to pay to have it removed.  Last week when I went back to mow the area was covered with honey mushroom clusters.

When I looked online, I found the Ringless Honey Mushroom (Armillaria tabescens) is a species of fungus in the family Physalacriaceae.  The mushroom is an infectious organism (pathogen) that is found in warm and dry regions, so it tends to be in southern areas.  It has been found in altitudes ranging from sea level to 4,300 feet (1,300 m).  the mushroom clusters frow quickly at 82 to 86F (28 to 30C) and more slowly at 41F (5C).  The species has a golden, honey-colored cap, white spores, narrow to broad pinkish/brown gills, and thick, cluster stalks.  This type of mushroom grows from late summer to early winter throughout the United States, including Arkansas.  You can often find the Ringless Honey Mushrooms in Oak Tree Stumps and Trunks in local parks.

The honey mushroom is a plant pathogen and is often found to attack trees that are already stressed or have a wound (like what is left of my elm).  The mushroom can spread its mycelia and get into the trunk or root of a tree.  The fungus can spread its mycelia throughout the root and trunk system and form mycelial mats (the root-like structure of a fungus).  Mycelia is damaging to trees because they absorb the nutrients by secreting enzymes to breakdown the plant material.  It specifically breaks down the support tissue of the plant (lignin) because it is a white rot.  The root system of the downed elm was expansive, and that explains the number of mushroom clusters I found in the back area of our yard.  Another website stressed you should kill these mushrooms when you see them as they are considered a parasitic fungus that will attack and kill your trees by depleting them of water and nutrients.  

Thoughts:  One interesting fact is that the ringless honey mushroom grows underneath the ground, rather than on top of it.  The best way to get rid of the mushroom is to destroy its roots beneath the ground.  Since I had come back to the area to mow, I went ahead and mowed most of the mushroom clusters but did preserve one large cluster so I could examine it further.  I was surprised when I went back to the area to see all the mushroom clusters I mowed were gone.  The mower was set too high to cut them down and had only damaged the tops, but all that was left (except for the big one) was white patches on the ground.  I assume that is the remains of white rot.  Like most species in nature, even pathogens have purpose and worth.  The mushroom in my back yard was busy breaking down the remains of the tree roots I had left in the ground.  This will eventually allow another tree to grow in the same spot.  Each species has a unique place in the local ecosystem.  Nature will return systems disrupted by human activity back to balance, but it may take hundreds of years or more.  Humans may not have that much time to wait.  Act for all.  Change is coming and it starts with you.

October 20, 2023

I received several likes and comments from my “Last” blog, and I thought I would share what my sister in Maine said.  She had also brought in the last of her green heirloom tomatoes and hoped they would ripen on the counter.  When she had cleared away the foliage and ripped up the vines there were two ugly cucumbers (Cucumis sativus) hidden among the undergrowth.  Together the tomato and cucumber may provide toppings for a tasty salad.  The last item was a huge sunflower that had been growing in the garden.  I have occasionally grown sunflowers along the back fence (from spilled bird seed) and had intended to plant several rows of sunflowers in the front bed (maximum sunlight), but again this was one of the projects life had thwarted this year.  My sister’s sunflower had been grown purposefully and she was hoping to harvest and dry the seed.  Perhaps another tasty morsal for her growing salad.

When I looked online, I found the common sunflower (Helianthus annuus) is a species of large annual forb of the genus Helianthus that is commonly grown as a crop for its edible oily seeds.  Apart from cooking oil production, sunflower is also used as livestock forage (as a meal or a silage plant), as bird food, in some industrial applications, and as an ornamental flower in domestic gardens.  Wild sunflower is a widely branched annual plant with many flower heads, but the domestic sunflower often has only a single large flower head (inflorescence) atop an unbranched stem.  The plant has an erect rough-hairy stem that reaches a typical height of 10 feet (3 m), but the tallest sunflower on record reached 30 feet 1 inch (9.17 m).  Sunflower leaves are broad, coarsely toothed, rough, mostly alternate, and those nearest the bottom are largest and commonly heart shaped.  The plant was first domesticated in the Americas and seeds were brought to Europe in the 16th century.  The seeds and oil quickly became a widespread cooking ingredient.  The bulk of industrial-scale sunflower production has now shifted to Eastern Europe.  During 2020 Russia and Ukraine produce over half of worldwide seed production.

The common sunflower was one of several plants cultivated by the Indigenous peoples in prehistoric North America as part of the Eastern Agricultural Complex.  It was once thought the sunflower was first domesticated in the (now) southeastern US around 5,000 years ago.  Recent evidence indicates the species was instead domesticated in Mexico around 2600 BCE as the seeds were found in Tabasco, Mexico, at the San Andres dig site.  The earliest known US examples of a fully domesticated sunflower have been found in Tennessee, dating to around 2300 BCE.  Other early examples come from rock shelter sites in Eastern Kentucky.  Many of the Americas indigenous peoples used the sunflower as the symbol of their solar deity, including the Aztecs and Otomi of Mexico and the Incas in South America.   Of the four plants known to have been domesticated in eastern North America that have become important agricultural commodities, the sunflower is currently the most economically important.

Thoughts:  During the 18th century, the use of sunflower oil became very popular in Russia, particularly with members of the Russian Orthodox Church, because fasting traditions only allowed plant-based fats during Lent.  The sunflower was commercialized in the early 19th century in the village of Alekseyeva by a merchant named Daniil Bokaryov, who developed a technology suitable for its large-scale extraction.  The town’s coat of arms has included an image of a sunflower ever since.  That makes the sunflower a mix of (indigenous) American discovery and Russian ingenuity.  To quote Rocky IV, “During this fight I’ve seen a lot of changing . . . if I can change, and you can change, everybody can change!”  That is wisdom to strive for.  Act for all.  Change is coming and it starts with you.

October 19, 2023

As I have been harvesting the last of my vegetables this last week, I have been dislodging the baren plants and throwing them over the patio fence.  That allows me to come along later with my mower and mulch them into the ground.  I mentioned earlier how I had harvested my last batch of jalapeño peppers (Capsicum annuum) and four of my Arkansas Traveler (Solanum lycopersicum ‘Arkansas Traveler’) tomatoes.  I did leave two of the travelers with larger green tomatoes on the vine as there is a chance for weather in the mid-70’sF (23 C) this week.  Several have now started to turn red, so it is just a race to see if the weather can ripen the last few tomatoes on my two vines before the cold shuts them down.  I only grow a limited variety of vegetables, but I am considering increasing the types next year.  That made me wonder when produce ripens in Arkansas and what are the last crops available.  

When I looked online, I found there are several types of Arkansas crops that are harvested in October.  This marks the end of the season for fruit trees like apples and Asian pears.  Second crops of greens (generic for edible plant leaves), along with broccoli (Brassica oleracea var. italica) and cabbage (Brassica oleracea var. capitata) can last into November, weather permitting.  A variety of species of gourds (family Cucurbitaceae; pumpkins, squash, and watermelons), along with my tomatoes all tap out as the last of the warm days leave and the plants succumb to the cold.   I had mentioned how the various herbs can be grown and harvested from April through October, and if they are in a transportable container (and cared for) can be moved inside and last throughout the winter.

Thoughts:  I had started this year’s planting season with high hopes (again).  I planned to plant several new varieties of vegetables along with my usual tomatoes and potatoes.  Life got in the way at the beginning of planting season and my expectations fell short.  Now that I have harvested the last of my crops, I have reflected on the fact that if this was subsistence farming, I would be in for a bad winter.  My grandmother used to have a large vegetable garden (1/2 ac/0.2 ha) where she grew the vegetables to be canned and preserved for the winter.  I heard grandfather told her if she would allow him to grow wheat on the garden space, she could afford to buy what she needed from the produce store in town.  While I am not there yet (nor have the amount of land) it is not far from my own reality.  Still, I am committed to try and reduce my carbon footprint.  Act for all.  Change is coming and it starts with you.

October 18, 2023

(AP Photo/El Imparcial, Julian Ortega, File)

I found a reprint of an AP article in the Business section of yesterday’s local newspaper that addressed a complaint filed against Mexico’s biggest copper producer.  The Grupo Mexico mining company was involved in the August 2014 mine spill which sent 10 million gallons (40 million liters) of acidified copper sulfate from a waste reservoir at Grupo Mexico’s Buenavista mine into the Sonora and Bacanuchi rivers.  Maria Luisa Albores González, head of Mexico’s Environment Department, said there are still “alarming levels of air, water and soil pollution across 94 square miles (250 square kilometers) to this day.”  The mining company closed its remediation fund in 2017, arguing that it had met its legal requirements.  The government contends the closing was premature and is asking the courts to order the establishment of a new fund.  In the original agreement Grupo Mexico had promised to establish 36 water treatment stations.  Only 10 were installed and only two of those were finished, and those two quickly ran out of funding.  Activists in the affected area were cautiously optimistic after the government’s legal action.

When I checked online, I found Grupo México is a Mexican conglomerate that operates through the divisions of transportation (GMxT), mining (Minera Mexico), and infrastructure (Fundacion Grupo Mexico).  Grupo’s transportation division operates the largest rail fleet in México, with 6,935 miles (11,000 km) of track, more than 800 engines, and 26,300 coaches.  The track interconnects five major inland Mexican cities, five cities along the border with the United States, and 13 seaports (5 on the Pacific Ocean, 8 on the Gulf of Mexico).  Mining is Grupo México’s largest division, operating 14 mines and 52 plants in Mexico, Peru, the US, Argentina, Chile, Ecuador, and Spain.  The division operates as Americas Mining Corporation, whose main subsidiaries are Southern Copper Corporation in México and Perú, American Smelting and Refining Company (ASARCO) in the United States, and Minera Los Frailes in Spain.  Grupo México is the largest mine operator in Mexico and Peru, as well as the third largest in the US.  The company is primarily focused on the extraction of copper and is the world’s fourth largest copper producer and controls the largest copper reserves in the world.

Grupo Mexico was founded by Raúl Antonio Escobedo and Larrea Mota Velasco in 1978 and purchased several of the countries key copper mines after the government of Carlos Salinas declared the state mining company bankrupt in the early 1980’s.  By 2000, Grupo México was responsible for 87.5 % of Mexico’s copper production.  Grupo holdings also have a history of pollution and mining disasters.  The Sea of Cortés acid spill (2019) leaked 792.5 gallons (3,000 liters) in northwestern Mexico.  The Rio Sonora spill (referenced above, 2014) sent 52,318 cubic yards (40,000 m³) of copper sulphate into the Sonora and Bacanuchi Rivers.  Grupo was also involved in the Pasta de Conchos mine disaster (2010) which gained worldwide attention for the 33 miners trapped in Copiapó, Chile.  In the US, the Environmental Protection Agency (EPA) has found Grupo’s ASARCO operation responsible for the environmental pollution at 20 Superfund sites across the country.

Thoughts:  When I was with the state of Utah in the late 1980’s I worked with the EPA and ASARCO on remediation of one of the superfund sites.  The lead and copper smelting industry had polluted the entire Salt Lake Valley at the turn of the 20th century, and litigation brought by the local farmers closed all but the ASARCO site.  ASARCO later purchased the lead smelter turned steel mill which the EPA was going after.  The settlement defined cleanup for the site and residences in the surrounding blocks.  The original lawsuit specified acidic rain killed everything in a swath 15 miles long.  Remediation is never sufficient to counter the havoc wrought.  Act for all.  Change is coming and it starts with you.

October 17, 2023

The weather is turning colder with nights down into the high 40’sF (4.5’sC) and days in the high 60’sF (15.5’sC).  Even though I have harvested the last batch of (nearly 20) jalapeño peppers (Capsicum annuum) I have allowed my six Arkansas Traveler tomato plants (Solanum lycopersicum ‘Arkansas Traveler’) to continue.  They are filled with dozens of small unripe green tomatoes.  Yesterday I decided there was not much hope for the fruit to ripen and thought I would harvest and then see what I could do with it.  Since Melissa is from the South, she had often spoken of the fried green tomatoes her family had eaten when the end of the season arrived.  We have recently purchased an air fryer to get away from the added fat that comes with fried foods.  Still, I am always looking for different types of uses for my produce.  That was when I found “10 ways you can use green tomatoes” on Oddbox.

When I checked online, I found the Oddbox story began in 2016 when the founders tasted a delicious but ever-so-slightly ugly tomato from a market in Portugal.  What struck Emilie and Deepak was they only saw identical-looking fruit and vegetables in their supermarkets.  When they began to dig, they found nearly 40% of food produced globally goes to waste because it was “too odd” or because growers have “too many”.  The Oddbox mission is to rescue those fruits and vegetables, at the same time making sure all the energy and water that went into growing it are put to good use.  The company (based in the UK) specializes in procuring odd and surplus fruits and vegetables from local producers and offers the products in home boxes to a community of food waste fighters, enabling customers to get a variety of fresh produce and contribute to a sustainable environment.  The company now works directly with growers to deliver thousands of boxes every week and is continuing to grow.

Oddbox not only delivers oddly shaped fruits and vegetables to consumers, but their website also offers recipes for using them.  There are two types of green tomatoes.  Sometimes, they are a separate variety of heirloom tomato that are still green when ripe.  Heirloom green tomatoes like Aunt Ruby’s German Green (Solanum lycopersicum ‘Aunt Ruby’s German Green’) is a beefsteak tomato that tastes like a typical red tomato.  More often, green tomatoes are just tomatoes that missed the chance to ripen (like mine) before the weather started to get colder.  These tomatoes are safe to consume either raw or in a cooked dish.  One of the recipes I found was for green tomato paste, or a variety of salsa verde.  The ingredients called for 2 pounds (900g) of green tomatoes, 4 mild chili peppers (1-1/2 of my hot jalapeños), one coarsely chopped onion, and 3 garlic cloves.  These are cooked for 10 minutes along with

1 teaspoon salt, 1/4 teaspoon ground cumin, 1 tablespoon olive oil, and 3 tablespoons water (I added a little more).  The mixture is brought to a boil and then simmered over medium-low heat for 10 minutes (stirring occasionally).  I added 2 tablespoons of fresh lemon juice and 1 tablespoon sugar and simmered for another 5 minutes.  Finally, I mixed the paste with a hand blender to get the consistency I wanted (btw: it tastes great). 

Thoughts:  The Oddbox mission is to ensure oddly shaped (but edible) food reaches the market.  Global food waste prior to reaching the consumer accounts for 2.5 billion tons each year and is responsible for 10% of all greenhouse gas emissions.  That means the environmental impact of wasting this food is about 248 times larger than plastic.  This is food that can be eaten, meaning it can also address world hunger.  I have begun to take a different attitude toward the vegetables I grow in the garden.  While they seldom look perfect, they are often tastier than what I buy at the store.  Oddbox knows that just because something looks different than we are used to does not mean it is worthless.  The same can be said about our encounters with other humans.  Act for all.  Change is coming and it starts with you.

October 15, 2023

After removing the potato plants (not “harvest” because I grew so few) from one of the back beds there is not much that has taken hold.  That was in part due to the straw mulch, which was still over most of the area, but also because Loki kept digging holes in the bed.  While I still intend to amend the soil and mulch the bed before winter, I have not got that accomplished.  When I removed the potato plants and grass there were some weeds that had already established in the perimeter along the house.  Now that they have access to the sunshine they have begun to thrive.   When I checked the bed this morning the plants had pink flowers that were in full bloom. 

When I checked online, I found Pennsylvania Smartweed (Polygonum pensylvanicum), also known as pinkweed, is a species of flowering plant in the buckwheat family, Polygonaceae.  It is native to parts of North America and is widespread in Canada and the US and has been introduced in parts of Europe and South America.  Pennsylvania smartweed is a variable annual herb that grows from 4 inches (10 cm) to 6.5 feet (2 m) tall.  The upright, ribbed stems can be either branched or unbranched and the lance-shaped leaves have a short stalk that attaches the leaf blade to the stem (petiole) that is able to twist the leaf to face the sun.  This produces a characteristic foliage arrangement (spacing of blades).  The petiole and a blade are about 1.5 to 6.5 inches (4–17 cm) long but may grow up to 9 inches (23 cm).  The flowers have five pinkish or greenish tepals each a few millimeters long.  The seeds are black, shiny flattened, almost round.  The plant grows in moist, disturbed habitat types, such as ponds, reservoirs, riverbanks, irrigated fields, and ditches (as well as garden beds).

Pennsylvania smartweed is considered an important part of the habitat for waterfowl and other birds, which use it for food and cover.  At least 50 species of birds have been observed feeding on the seeds, including ducks, geese, rails, bobwhites, mourning dove, and ring-necked pheasant.  The seeds and other parts are eaten by mammals such as the white-footed mouse, muskrat, raccoon, and fox squirrel. 

The smartweed family (Polygonaceae) includes around 900 species that range from annual herbs to perennial trees, and includes buckwheat, dock, and rhubarb.  The genus Polygonum typically has simple leaves which often have dark blotches on them.  In some manuals, Pennsylvania smartweed is called Persicaria pensylvanica.  Native Americans have various uses for the plant.  The Chippewa use it for epilepsy and the Iroquois use it for horse colic.  The Menominee take a leaf infusion for hemorrhage of blood from the mouth and post-partum healing and the Meskwaki use it on bleeding hemorrhoids.

Thoughts:  I found it interesting that smartweed was listed as an invasive weed on agricultural sites even as it is sold on garden sites as wildflower.  Agricultural sites focused on the invasiveness in hay fields and cultivated lands.  Garden sites point to the different types of insects that seek out the plant in search of nectar (bees, butterflies, moths, wasps, flies, and beetles).  Bird sites say the plant and seeds are an important part of diet for various waterfowl and gamebirds.  The seeds eaten by birds are not fully digestible, so the partially digested seed is spread in bird droppings.  Yet another case of one person’s weed being a viable part of other bird and human ecosystems.  Act for all.  Change is coming and it starts with you.

October 13, 2023

The lead story in October’s “Audubon Advisory” concerned a bipartisan bill in the US Senate that advanced out of the Senate Committee on Environment and Public Works on September 27, 2023.  The bill, Strengthening Coastal Communities (SCC) ACT of 2023, was jointly bill introduced by Senators Tom Carper (D-DE) and Lindsey Graham (R-SC).  The legislation will update and modernize the Coastal Barrier Resources Act, a law that for more than 40 years has protected undeveloped beaches, wetlands, and other coastal areas while saving taxpayers billions of dollars.  Portia Mastin, coastal conservation policy manager at National Audubon Society, said, “Birds and people urgently need more protection on our coasts from storms and flooding.  This bill meets that challenge by extending the benefits of the Coastal Barrier Resources Act to more areas along the coast and will also identify the areas where marshes and beaches can naturally migrate inland as sea levels rise.”  If this bill is not enacted the country will risk losing many of the wetlands for birds, and the storm buffers protecting development along the coast.

When I checked online, I found the Coastal Barrier Resources Act (CBRA) was established in 1982 and prevents most federal spending in flood-prone coastal areas.  The current CBRA system includes 3.5 million acres (1,416,399 ha) of undeveloped barrier islands, beaches, inlets, and wetlands along the Atlantic Ocean, Gulf of Mexico, Great Lakes, Puerto Rico, and the US Virgin Islands.  In 2022, the Department of the Interior recommended that Congress add over 277,000 acres (112,097 ha) to the CBRA system in the nine states hit hardest by Hurricane Sandy to save federal tax dollars offer and better protect the Atlantic Coast from New Hampshire to Virginia against future storms.  The SCC Act will implement those recommendations and add new protected areas to the system in other states that are vulnerable to storms and sea-level rise, including South Carolina, Florida, and Louisiana.  The Act will also authorize a pilot project to identify new upland areas where beaches and marshes can naturally migrate as sea levels rise, along with expanding the definition of coastal landforms included.

A recent study found that CBRA is highly effective at achieving its intended goals.  The 1980’s bill reduced coastal development by 85% in flood-prone areas, reduced flood damage in nearby human communities by 25%, and added an ecologically important layer of protection for these established human communities.  The protection also ensures threatened species of coastal birds like the American Oystercatcher (Haematopus palliatus) and Piping Plover (Charadrius melodus) that rely on these areas can nest, feed, and rest safely.  When environmentally healthy, the protected habitats act as nature’s speed bumps, buffering nearby communities from storms and floodwaters.  While neither act prohibits construction (and destruction of the natural buffers), they do remove taxpayer-funded subsidies for development in hazardous coastal areas.  The CBRA promotes public safety and has already saved federal taxpayers nearly US$10 billion over 25 years.  The SCC Act will extend protections further.

Thoughts:  Alongside the least tern (Sternula antillarum), piping plovers have an unusual relationship with coastal mining.  Where most species suffer habitat loss from mining activities, these birds are known to nest in the waste sand piles generated by nearby mines as the replacement for lost sand bars along coastal areas.  The sand piles remain topped-up and hostile to vegetation while the mining activity continues.  Modern mining practices now transport much of this waste sand to more remote areas or reuse it commercially, which limits colonization opportunities for these birds.  Abandoned mines often serve as construction sites for housing developments.  That means bird habitat and sand dune buffers are removed and the areas become vulnerable to storm surge and flooding.  Protecting coastal habitat is good for both humans and birds.  Act for all.  Change is coming and it starts with you.

October 12, 2023

I receive a free weekly town newspaper that provides the usual local sports, school, city hall, and local interest stories that were previously reported in nearly every small town in America.  One of the special interests stories this week was about the bear hunt season in Arkansas.   You may recall last summer I commented on the bear that showed up in a wooded area near our neighborhood in the Arkansas River Valley.  The Arkansas Game and Fish Commission (AGFC) reintroduced bears into the Ouachita and Ozark Mountains (to the north and south of us) during the late 1950’s and 1960’s.  Bear season opened for hunting in 1980 and this year most of the state is open.  It is estimated that 700 animals will be harvested.  Muron Means, Coordinator for the Large Carnivore Program with AGFC, said without the hunters, sales taxes collected, and the work of AGFC scientists, the revival of hunting black bear in Arkansas would not have happened.

When I checked online, I found the American black bear (Ursus americanus), or black bear, is a species of medium-sized bear endemic to North America.  The animal is the smallest and most widely distributed bear species on the continent.  The American black bear is an omnivore whose diet varies greatly depending on season and location.  It typically lives in largely forested areas, but will leave forests in search of food, and is sometimes attracted to human communities due to the availability of food.  The International Union for Conservation of Nature (IUCN) lists the American black bear as a least-concern species, due to its widespread distribution and a population estimated to be twice that of all other bear species combined.  Along with the brown bear (Ursus arctos), it is one of only two modern bear species not considered by the IUCN to be globally threatened with extinction.  Today, black bear fatalities are mainly attributed to humans (vehicle accidents and hunting). 

The black bear was nearly eradicated from Arkansas due to predation for bear fat, which was used to make oil for lamps in cities like New Orleans and Galveston.  The oil was cheap but would leave dark greasy stains on the street if it was spilled.  The only bear meat I have ever tasted was bear jerky bought from a big box hunting chain.  I had always heard bear meat was greasy, and the jerky (at least) affirmed this.  Still, meat was number one of the four reasons given for why people in the US hunt bears.  The next reason is conservation.  Bears cause huge amounts of damage to the moose (Alces alces), deer (Odocoileus virginianus), elk (Cervus canadensis), and caribou (Rangifer tarandus) populations in the US.  The biggest reasons the black bear is hunted is for trophies, although it was stated this also included eating bear meat.  The final reason is for management.  As people encroach on bear territory, they become familiar to humans as a source of food (garbage).  The bear is then either relocated or shot. 

Thoughts:  The bear season in Arkansas shows that 80% of the black bears are harvested with archery equipment, and that is not unique for other states.  The reason is most people bait and bear hunt early, usually as soon as the season opens.  Most of the damage in the bear harvest is within the first couple of weeks of archery season.  The normal reason for wildlife hunting to be illegal is managing population, and bear hunting is legal because there is a healthy population.  While that may be good for the hunters, it is not so much for the bear.  Act for all.  Change is coming and it starts with you.

October 10, 2023

Photo: National Park Service

Buried inside of today’s front section of the local newspaper was a USA Today reprint on a new study on the footprints found in September 2021 in White Sands National Park, New Mexico.  Researchers from the US Geological Survey and an international team of scientists had announced the ancient human footprints were dated between 21,000 and 23,000 BP.  This discovery pushed the known date of human presence in North America back several thousand years (from 15,000 BP) and implied that early humans and megafauna co-existed for several millennia before the terminal Pleistocene extinction event (around 12,000 BP).  In a follow-up study, published October 5, 2023, in Science, researchers used two new independent approaches to date the footprints, both of which resulted in the same age range as the original estimate.  The 2021 results began a global conversation (and controversy) that sparked public imagination and commentary throughout the scientific community as to the accuracy of the ages.  The original ages were obtained by radiocarbon dating based on seeds of the common aquatic spiral ditchgrass (Ruppia cirrhosa) found in the fossilized impressions.  Aquatic plants can acquire carbon from dissolved carbon atoms in the water rather than ambient air, which can potentially cause the measured ages to be too old.   

When I looked online, I found seed and pollen dating is often used to establish relative chronologies when the material is stratified (layered) and can be securely dated.  All three pollen samples used for radiocarbon dating were found fossilized in the sedimentary rock that contained the human footprints.  Pollen dating can also complement other dating techniques, and pollen grains are “highly suitable” for radiocarbon dating.  Pollen grains have morphological characteristics that allow them to be identified into different taxonomic groups providing contextual information for dating the sample.  Combined with radiocarbon dates, pollen analysis can provide a more comprehensive understanding of the context of an archaeological site and help archaeologists construct a more accurate timeline of human activity.  In addition, pollen dating can provide “relative dates beyond the limits of radiocarbon (40,000 years)”.

The follow-up study focused on radiocarbon dating of conifer pollen which avoids potential issues when dating aquatic plants.  With three separate lines of evidence pointing to the same approximate age, it is highly unlikely that they are all incorrect or biased and together provide strong support for the 21,000 to 23,000-year age range for the footprints.  The researchers used painstaking procedures to isolate approximately 75,000 pollen grains for each sample they dated.  The pollen samples were collected from the exact same layers as the original seeds, so a direct comparison could be made.  In each case, the pollen age was statistically identical to the corresponding seed age.  In addition to the pollen samples, the team used a different type of dating called optically stimulated luminescence, which dates the last time quartz grains were exposed to sunlight.  This method found that quartz samples collected within the footprint-bearing layers had a minimum age of 21,500 years, providing further support to the radiocarbon results.

Thoughts:  Various theories have attributed the wave of megafauna (animals weighing over 100 lbs./46 kg) extinctions to human hunting, climate change, disease, or other causes.  The first humans in North America were thought to have arrived around 15,000 to 12,000 BP and coincided with extinction.  The footprints in New Mexico (23,000 BP) also supports the wide presence of humans across the Americas by 12,000 BP.  While human hunting alone may not have caused extinction, global extinctions are known to occur not long after the spread of humans into new areas.  This is a legacy we have the ability (if not the willingness) to change.  Act for all.  Change is coming and it starts with you.

October 09, 2023

Our trash service happens early on Monday mornings and that means I need to get the trash before I go to bed on Sunday night.  I usually make a run through the house to collect all the trash and then take it to the waste bin we keep in the garage.   That means I need to open the garage door, guide the bin between the cars parked in the driveway, and then maneuver it out to the street for pickup.  After coming back inside I pushed the controller to bring the door down when I noticed something clinging to the bottom of the door.  I brought the door back up and saw whatever was still attached to the door.  When I went to see what was on my door, I saw a long black stationary object.  I touched it to see if I could discern what it was.  Even though the antennae were not extended, it was clear I had a large garden slug on my garage door.

When I looked online, I found the black slug (Arion ater), also known as black arion, European black slug, or large black slug, is a large terrestrial gastropod mollusk in the family Arionidae, the round back slugs.  The size of the black slug varies from 3.9 to 5.9 inches (10 to 15 cm), reaching maturity at about 1 inch (2.5 cm).  It moves at the blistering speed of 1.8 inches (4.5 cm) per minute.  The black slug is generally deep black, but some adults are brown or even white.  Their pigmentation is known to darken directly with increasing latitude.  Young specimens tend to be brown or ivory whitish, turning to grey before becoming characteristically black at maturity.  Rust-brown individuals are arguably classified as a separate species called the red slug (Arion rufus).  The two species of slug can only be distinguished by dissecting the reproductive anatomy.

Most slugs retain a vestigial remnant of their shell (underdeveloped) which is usually internalized, unlike other terrestrial mollusks (like snails) which have external shells.  Without external shells, terrestrial slugs produce two other forms of mucus that facilitate locomotion and prevent death from drying.  Slugs possess both male and female reproductive organs, structures, or tissue (hermaphroditic).  Slugs are often decomposers but are also omnivores.  The black slug is this type, decomposing organic matter, preying on other organisms, and consuming vegetative matter including agricultural crops.  The black slug is native to Europe and is an invasive species in Australia, Canada (British Columbia, Newfoundland, Quebec), and the US (Pacific Northwest). The black slug often appears chunkier and slightly less elongated.  These are not a full-proof distinction and dissection is often the only way to isolate the species.  I did not perform a dissection but threw it in the trash which was picked up this morning.

Thoughts:  Usually when I encounter a slug it is while I am digging in my garden, not hanging on my garage door.  The black slug is and invasive species that has been introduced to southeastern Australia and North America.  The black slug is a voracious seedling predator and endangers sensitive ecosystems, but it is not yet clear what affects the slug may have on plant community composition.  The slugs are of special concern in fragmented ecosystems and areas with high shrub and tree cover.  I am hesitant to destroy even a slug and was glad I sent it to the landfill where it will be happy decomposing local trash.  This environment will protect my garden and help rid the city of debris.  This slug is yet another example of human activity introducing invasive species into areas without historic predators or controls.  This is a lesson that needs to be learned and heeded as we prepare to move into space.  Act for all.  Change is coming and it starts with you.