Tuesday, October 31, 2023

An Enchanted Hike Through the Enchanted Mesa

Tall flowering grasses line the path

I could spend tons of posts on the beauty that we saw when we stayed in the Boulder, Colorado area this last summer, but one of the more notable periods of our stay was when many of the so-called wheatgrasses were in flower.

The Enchanted Mesa trail in the Flatirons hiking area is considered a moderate trail, but I remember it was relatively easy and flat. You also get some good spectacular views along part of the way.

The arching flowerheads of T. intermedium

But the best part of hiking this trail is that large parts of it lie in savanna grassland, and in mid-July, the path is lined by masses of tall flowering grasses. 

These include the wheatgrasses Pascopyrum smithii and Thinopyrum intermedium, whose arching flowerheads are positively ethereal against the filtered sunlight, as well as the usual Bromus inermis.

I was accompanied by my wife in the hike, and although she is not a die hard grassophile like myself, even she had to marvel at the scenery and comment on it.

In fact, many of the hiking trails in the area had the same grasses in flower, and another notable hike that we did was at the Red Rocks trail

Red Rocks Trail in July 

In this case, the sight of the ancient red rocks rising above the flowering grasses that surrounded them was almost a religious experience, especially with the grasses dancing in sinuous waves to the gusting wind.

So the next time you're in the Boulder area in July, be sure to lace on your hiking shoes and take an enchanted trip to the Enchanted Mesa!


Sunday, October 29, 2023

The Ancient Fire and Grazing Grasslands of Madagascar

Two types of grassland, side by side

Whenever I take a walk outside, I am always struck by how various grass communities (whether natural or artificial) seem to have very distinct physical appearances. In today's suburban world of course, the most visible grass communities are the lawns that grace many homes. They're composed of grass species that are short and adapted to lots of mowing. But go to some nearby natural area like a pine and wiregrass savanna, and now much taller grasses dominate. 

The grass species that are found in each type of community can vary significantly, and this difference was a topic investigated by researchers in Madagascar. In this country, the vast old growth grasslands (which includes savannas) are in peril due to misguided afforestation efforts by some. This is because the common misperception (as in many other countries in tropical areas that were once colonized) is that these grasslands are the products of human activity and derived from areas that were once forests.

Cynodon dactylon, a major component of the grazing grassland. Yes, that's Bermudagrass, a common turf grass in the USA and elsewhere.

In their study, they examined (1) whether some species were associated together more often than not to form a specific assemblage or community. They also looked at (2) the functional attributes of each species with regards to flammability, palatability and tolerance to fire and grazing. These were:

  • Plant height - taller plants tend to be more flammable

  • Leaf thickness - thicker leaves tends to be less palatable

  • Leaf C/N ratio - leaves with higher C/N ratios tend to be more flammable

  • Leaf shape - wide short leaves are preferred by grazers as more palatable, while long narrow leaves ignite easily and burn more intensely

  • Plant bulk density - high bulk density grasses provide more forage per bite, whereas low density grasses provide more aeration for fires.

They found several fascinating and important things:

First, they found that, indeed, species tended to cluster together into distinct spatial assemblages. Some species tended to be found together with the same group of species more often than not, and only in certain locations.

Secondly, they also found that the species they studied in Madagascar could be divided into 3 distinct functional groups. The first functional groups showed adaptions for grazing, and are mostly short grasses with high bulk densities, and leaves that are short, wide, and thin. Many of these are mat-forming, using either rhizomes or stolons. The second functional group is adapted for fire, and is comprised of tall bunched grasses with thicker leaves, low bulk density and low leaf width to length ratios. They also found a distinct and third functional group that were intermediate between the two extremes. 

A fire adapted grass (Imperata cylindrica)

Finally, and most importantly, they found a relationship between the spatial assemblages and the functional groups. The functional group of a species influences which assemblage contains it (see table below).

Solofondranohatra CL et al, 2020

Thirteen of 14 species in the grazing functional group (92.85% of the total species exhibiting grazing adaptations) were found in assemblage 1. In contrast, 12 of the species in assemblage 2 were from the fire functional group, and none were from the grazing functional group. They also found relatively high levels of endemism in each assemblage.

All these findings support the view that the various Madagascar old growth grasslands have been shaped by either fire or grazing, and that the levels of endemism, diversity, and evolutionary ages of the species means that these complex assemblages were formed and have been in existence millions of years before the advent of human activity in the island. Humans only entered the picture in this area around 10,500 before the present (BP), and only made significant changes to the landscape around 2300 years ago. Thus, it is likely that many of the grasslands in Madagascar are not secondarily derived due to human activity, but are natural and ancient environments. 

This study again highlights the importance of not simply taking as gospel the widespread belief that all grasslands in tropical areas are secondarily derived, and a product of human activity and degradation of forested areas. It should give pause to those who want to go full on ahead with afforestation efforts without careful study. Beyond the stupidity of destroying ancient habitats and the diverse plants and animals within and replacing them many times with commercial timber, such projects have so far yielded mostly massive failures, mainly because they try to introduce plants to areas that are not conducive to their survival, instead of trying to address the underlying economic and societal conditions that foster the destruction of forests and the creation of real secondary grasslands.

Note: Interestingly, the researchers noted that the loss of the ancient grazers that maintained the grazing-adapted grasslands, may have been ameliorated by the introduction of cattle and other new grazers by humanity.


Solofondranohatra CL, Vorontsova MS, Hempson GP, Hackel J, Cable S, Vololoniaina J, Lehmann CER. 2020 Fire and grazing determined grasslands of central Madagascar represent ancient assemblages. Proc. R. Soc. B 287: 20200598. http://dx.doi.org/10.1098/rspb.2020.0598

Sunday, October 22, 2023

Creepy Corn Day (aka Halloween)

Corn stalks for sale at Lowes in New Jersey 

It's that time of the year again when spooky shenanigans slither into the normal daily lives of people. It's when kids in costumes defy the odds and gather candies from strangers, and the Simpsons treat us to another round of entertaining stories about really weird stuff. 

Yes, it's Creepy Corn Day (aka Spooky Corn Day, aka Halloween), which should be that celebration's official name, given that so much of the traditions associated with this day are related to the species Zea mays (corn/maize).

This was the thought that came to me while I was walking outside a Lowes in New Jersey last week and I saw another bunch of dried corn plants for sale. It made me wonder about all the other things during Halloween that involved this grass.

Corn Shucks

The dried bunches of corn that I saw are called corn shucks, and they were traditionally used by farmers during the end of the harvest to dry out the corn and to clear land for other plantings. The dried stalks were later used for bedding and feed for animals, and the corn itself was milled. During modern times, mechanical harvesters have obviated the need for this, but their common use in the past made people associate them with Fall and Halloween. Plus, they truly do look kinda spooky.

We're gonna get ya!

Candy Corn

I was not so familiar with this particular Halloween tradition, but it seems is very popular with kids. It's a type of candy that boasts a whopping 28 grams of sugar per handful, and is made out of various ingredients, including (you guessed it!) corn syrup. It is the most popular candy treat during Halloween in many states, and in 2019, it was estimated that more than 95% of holidays shoppers bought some of this confectionary. More than 9 billion of the candy is produced each year!

The candy seemed to have been first created by the Wunderlee Candy Company in Philadelphia in 1880s, but its popularity and association with Halloween did not occur until the 1950s, when the tradition of handing out candies to visiting children became popular.

Candy Corn

Corn Mazes

The idea and implementation of plant mazes has been with us since ancient times, but the use of corn fields to create mazes during the Autumn was not started until the early 1990s.

In 1993, a man named Don Frantz was flying over a corn field when the idea came to him. It didn't hurt that he had been involved in other creative endeavors, including  shows in Broadway and the Super Bowl halftime show. Frantz and another man named Adrian Fisher created the first corn maze in Lebanon Valley College in Annville, Pennsylvania. They named it "The Amazing Maize Maze", and  the maze was modeled in the shape of a dinosaur named "Cornelius the Cobasaurus".

The popularity of corn mazes spread, and today they are another staple of  Halloween...ahem...I mean, Creepy Corn Day.

Saturday, October 14, 2023

Following Buffaloes

Male flowerhead of Bouteloua dactyloides (Colorado)

In 1977, a movie called Star Wars was just starting out on its path to becoming one of the most successful science fiction franchises in history. Marty McFly had yet to drive his DeLorean back to the future; Arnold Schwarzenegger was a relatively unknown bodybuilder whose metamorphosis into the Terminator was years into the future, and even E.T. had no need to phone home just yet.

Male flowerheads of Bouteloua dactyloides (Colorado)

In this same year, in a university town in New Jersey, plant clippings from a garbage bin that was being emptied by trash collectors accidentally fell onto a lawn of Kentucky Bluegrass (Poa pratensis). The clippings had come from a nearby Rutgers University greenhouse that was housed in the Nelson Biological Sciences building. A grass species from the high plains of Oklahoma and Kansas was being grown there for turf studies, and its introduction into the heavily trampled and disturbed grounds of the Rutgers Busch Campus was in hindsight a fortuitous event (Quinn, 1998).

Front lawn of Library of Science and Medicine at Rutgers Busch Campus. Red arrows point to B. dactyloides clusters

Forty six years later, I knelt on the same grounds in front of the next door Rutgers Library of Science and Medicine (LSM) building and examined tiny male flowerheads of Bouteloua dactyloides (commonly called buffalo grass in the USA). They marked the occurrence of the same plant(s) that had escaped almost five decades earlier, and their expansion and spread using both stolons and seeds moved me. I felt a sense of being connected through time  by this humble native grass to that past accident so long ago.

It was relatively easy to determine the extent of the spread at this time of the year. The species starts to brown earlier during autumn, and it stood out against the still darker green masses of other turf grasses. I could see clearly that it was now present on different lawn areas that were separated by concrete paths, and that some of the irregularly shaped clones were quite large.

Mobile phone pic of male flowerheads of Bouteloua dactyloides in lawn of Library of Science and Medicine, Rutgers University Busch Campus. 

I noted the GPS coordinates and measured the sizes of the clusters that I could ID as B. dactyloides. Many were vaguely round, oval, or rectangular in shape, with diameters of half a meter for the smaller ones, and sizes that approached bedroom size for some of the larger ones.

Room size cluster of Bouteloua dactyloides (light brown area) next to Rutgers Library of Science and Medicine

The survival of the original plant for almost half a century is notable, because B. dactyloides has been touted as a low-maintenance, drought tolerant, and native alternative to the usual European grasses that dominate the northeast lawns in the USA today. I myself considered its use on my own lawn in NJ at one time some years ago. 

Unfortunately, its intolerance to shade and its inability to be competitive in rainy wet areas has always raised questions as to whether it would be a successful replacement to the proven imported turf grasses. In this case, not only had it survived for almost half a century, but it had managed to spread significantly against formidable opposition from forbs and other types of grasses such as P. pratensis. This helps prove that it is possible to use this species as turf grass and for erosion control in disturbed soil in the Northeast.

Female reproductive structure of Bouteloua dactyloides (Colorado)

As an important aside, I know some people follow trees over time, but there are many herbaceous plants that can exist for very long periods, and it is just as rewarding to follow their lives over time. In fact, the longest lived organism in the world is a herbaceous seagrass, which has been calculated to be 80,000 to 200,000 years old  (Arnaud-Haond et al, 2012)! It is amazing to think how the world has seen so much change during that astounding duration. 

In the same way, although spanning an exponentially shorter span, when I first laid my eyes on the spreading clusters of B. dactyloides in front of the LSM library a couple days back, I truly felt an emotional attachment to them. I studied at this same university in the 1990s, and I had likely passed by the same individual many times on the way to my studies. It made me feel the ticking of time with a more visceral emotion than mere objective contemplation, and it humbles me that this clonal individual might still be flourishing and thriving and growing when I'm long gone from the world. 

Literature Cited:

Arnaud-Haond S, Duarte CM, Diaz-Almela E, Marbà N, Sintes T, Serrão EA. Implications of extreme life span in clonal organisms: millenary clones in meadows of the threatened seagrass Posidonia oceanica. PLoS One. 2012;7(2):e30454. doi: 10.1371/journal.pone.0030454. Epub 2012 Feb 1. PMID: 22312426; PMCID: PMC3270012.

Quinn, J. A. (1998). Natural Expansion of Buchloe dactyloides at a Disturbed Site in New Jersey and Its Implications for Turf and Conservation Uses. The Journal of the Torrey Botanical Society, 125(4), 319–323. https://doi.org/10.2307/2997245

Tuesday, October 10, 2023

Grasses all day, every day, and grasses ever after, amen!

My life, as well as the lives of billions of other people, are intertwined with grasses...we are touched by them....from the time we wake up in the morning, to the time we sleep at night.

This was what I tried to convey during a talk with Matt Candelas of In Defense of Plants.

In my case, when I wake up in the morning, I (like literally billions of other people around the world) encounter members of the grass family, or derivatives of it, throughout the day.

The first thing I do in the morning is eat a bowl of oatmeal, and oatmeal of course is from the grass Avena sativa

When I eat my bowl of oatmeal, I put  some sugar into the mix of fruits, and around 80% of sugar in the world is derived from a grass, sugarcane (Saccharum officinarum).

I walk out to my car, and I'll see suburban lawns stretching to the horizon, and the turf grass of course is a mix of various grass species. In Florida it would be Stenotaphrum secundatum (St. Augustine grass), Paspalum notatum (Bahia grass) and maybe Cynodon dactylon (Bermuda grass), while in the Northeast you get various mixes of Poa pratensis (Kentucky bluegrass), Festuca spp, and Lolium spp.

Such species are what people normally think of when you mention the word "grass" to them. Ornamental grasses also fall into this category of grasses that are used in landscaping.

When I drive my car to work, the ethanol in my gasoline tank is likely as not made from Zea mays. In fact, around 40% of all corn production is used as bioethanol!

During lunch, I might go out and get a burger, and where would that be without the bread that frames the delicious ingredients between them? Bread of course is from a grass that we call wheat,  (Triticum aestivum and its ilk).

Maybe I also eat some snacks for lunch, and if you are brave enough to look at the ingredients of your candy or chips, you'll probably find something called high fructose corn syrup in it. This is a very common ingredient of packaged foods, because it adds to the sweetness of the food, and this is of course derived from a grass that we already mentioned above, Zea mays (corn/maize).

In fact, if you live in the USA, your body is probably mostly derived from that single grass species. Here is a great documentary that explores in some depth the ubiquity of Z. mays in American life.  

Finally, during some part of the day, I'll probably eat rice (Oryza sativa) during either lunch or dinner (and sometimes breakfast too!). Rice is, of course, one of those grasses that have been essential in the creation and and molding of entire civilizations (which I'll look into next time).

And I'm not even including all the times we use bamboo implements and tools!

So no matter how you look at it, the family Poaceae is by far the most influential and important plant family in the world. It's grasses all day, every day, and grasses ever after, amen!