Environmental stressors – a curious nature

The Cowpen Daisy ….. One of the Happiest Sunflowers Ever!

Part 1 ….. Can There Be Too Many Sunflowers?

August 5, 2025

It was the Fall of 2024. A small cluster of Cowpen Daisies (Verbesina encelioides) flourishing on the severely disturbed ground surrounding our new home was going to seed. Waiting several weeks until the migratory birds ate their fill, I spent an hour or so collecting as many remaining dried seeds (cypselas) as possible, stuffing full two quart-sized ziplock bags. About 1/3 of the seeds I scattered around the house where they would overwinter on the ground. The rest were poured into large pill vials that were labeled with species name, location, and date, then placed in the refrigerator to simulate cold storage until Spring.

Cowpen Daisy cypselas (seeds) 08/04/2025 at Punch

It was late April 2025. The chances of heavy frost seemed a distant memory. My fingers crossed, I chose a sunny 42 degree morning to liberate those refrigerated seeds from 6 months of cold storage, and scattered them in disturbed areas not seeded last Fall. Then I waited like an expectant parent, watching for signs of germination, worrying that runoff from late season snows might wash away my scattered seeds, expecting that flocks of migratory birds would gobble them all up, and hoping for gentle rain showers to swell those thousands of seed coats to aid those tiny embryos in growing their first roots (radicles) and first leaves (cotyledons).

Then early June 2025. Success! Cotyledons were literally popping up everywhere, which meant the radicles were already expanding into the soil. They were especially crowded where I’d scattered all the cold storage seeds, and germination was obvious where seeds had been scattered the Fall of 2024. By early July, those Cowpen daisies were crowding out many of the other native species I’d also seeded in the same areas.

Backyard and overflow Cowpen Daisies, robust growth after Fall 2024 seeding (08/03/2025)

And now it’s early August 2025, and what a dazzling show! Even though the sunflower yellow flowers of Cowpen Daisy are small (2” wide), there are up to 75 long-stemmed flowers on each plant that can grow from 4-5’ tall! They are so dense, the backyard fence is hardly visible, our walking paths are totally draped with 4” long leaves, and if there’s a rattlesnake lurking around under our massive Cowpen Daisy canopy, we’d probably (hopefully) hear him well before he slithered into view!

Goals and Lessons Learned

I’ve learned a lot by parenting these Daisies; from the best time to scatter seed (in the late Spring following cold storage) and where (not so close to other desirable natives or pathways), to managing the mass of growth (by organizing through selective removal). Our initial goal of seeding and growing native plant species was to attract and help feed wildlife (pollinators, reptiles, rodents, birds and mammals), and we are optimistic that achieving this goal long-term seems realistic with the success we’ve had to date. However, because so many of our native plants are losing the battle against habitat loss caused by invasive species encroachment and takeover, land development, and climate change, we will continue to explore ideas to expand our initial goal to address the habitat situation. As we gain insight about the best native plants to grow to help restore our disturbed soils, we will learn and share with our neighbors those species that: are drought tolerant; aid in building soils; are effective at invasive weed suppression; provide wildlife benefits; and increase plant diversity.

Cowpen Daisy and pollinator 08/01/2025 at Punch

Happy – Happy – Happy! Will I be collecting Cowpen Daisy seed again this Fall? You bet! Having all that sunshine yellow around our home is thrilling. Every morning all those thousands of sunflower faces looking East towards a new day are about the happiest sight ever! And having such wild, uninhibited growth of a native annual out our back door has been ideal for observing the pollinators that benefit from the abundant nectar and pollen, enjoying the aerial acrobatics of several phoebe families that have been feasting on those pollinators, and promises to be a perfect spot for bird watching this Fall when all those cypselas ripen into high protein food.

Can’t wait!

Do you ‘know’ a special native plant? How about a native butterfly garden? Are you a bird watcher? Maybe you enjoy the occasional deer, coyote, or bobcat wander through your yard? Please share your favorite wildlife encounter!

As always, thanks for stopping by!

Bordered Patch (my photo/2023 – on butterfly bush)

Hooked on Trichomes … The Curious Nature of ‘Mentzelia’

July 29, 2025

You must awake when the first rooster crows to enjoy the floral beauty of a fully flaired Blazingstar blossom. Appropriately named, these gorgeous flowers display a radiant combination of spoon-shaped petals, petal-like stamens, and hundreds of thread-like stamens, all colored in bold sulfur yellows, distinctive pale orange-yellows, brilliant star whites, or fluorescent blues, based on species. These superbly showy flowers unfurl overnight atop tall white, branching stems that resemble candelabras with narrow lobed green leaves. These large, 2” diameter flowers belong to the Mentzelia genus, plants that are all native to the Americas, and represented by 60-80 species, most found in the desert southwest.

In 1753, Carl Linneaus gave this plant its genus name, Mentzelia, after German botanist and sinologist Christian Mentzel. (Did you know a Sinologist is a specialist in the study of Chinese language, literature, and civilization? Huh!) But perhaps more fascinating and what’s always ‘captured’ my complete attention (and blue jeans) is that the Mentzelia genus fits perfectly in the Loasaceae family ….. commonly referred to as the Stickleafs.

About those leaves ……

Being primarily a day-time hiker, my first encounter with a Blazingstar occurred simultaneously with a misstep into the plant. Noticing some resistance in making my escape, I looked down at the ground and discovered my jeans had a collection of stuck leaves from my boots on up. And the leaves were really stuck tight along their entire length! Removing those leaves was like peeling a banana, only tougher. Wait! Forget the banana peel. Removing those sticky leaves sounded like and felt like tugging on and separating Velcro! I was reminded of the familiar ‘ripping’ noise made when Velcro hooks are forcibly released from their loops!

Eureka!!

Nature is full of surprises. Were the Stickleafs the source of accidental inspiration for today’s handy hook-n-loop fastener, called Velcro? Almost, but not quite! As it turns out, the tiny hooks on Cocklebur seedpods inspired a Swiss engineer to develop Velcro in 1941. But not to change subjects too much …….The reasons Stickleafs could’ve been the inspiration for Velcro, is similar to the Cocklebur story, but, I think, even better. Here’s why ……

The seedpods of both plants have tiny hooks that readily adhere to clothing and fur. And it was the hooks’ tenacity for stick-to-it-tiv-ness that grew the original Velcro idea. But Stickleafs go even further in ‘reinforcing’ the fastener concept. Not only does the seed pod (capsule) of Stickleafs have a covering of tiny hooks, but both leaf surfaces and even the stems of plants in this family can have multiple types of minuscule grappling-hooks and barbed needles, called Trichomes, visible only with an electron microscope. I summarize that if the Swiss engineer was visiting America in 1941, and had the good fortune to walk into a Mentzelia plant, he undoubtedly would’ve been super inspired to develop Velcro. After all, it’s the leaves that stick fast to clothing, resemble a strip of Velcro, and hold tight, mimicking an ideal hook-n-loop fastener.

Hooked on Trichomes

And now for the curious nature of the Mentzelia genus. When coming across the Adonis Blazingstar (Mentzelia multiflora) over the past 8 years, it’s been fun to inspect the leaves, remove one and intentionally stick it to Roy’s jeans or mine. I’ve then wondered how this plant ‘sticks’ so well, and why. The time for answers arrived this month, and what I learned was fascinating. It’s all about Trichomes.

Trichome is a botanical term used to describe the small hair-like structures that occur somewhere on a plant; typically on plant leaves. Trichomes can be found throughout the plant kingdom (like on Cannabis sativa); they aren’t unique to the Stickleaf family, and are found on all species of the the Mentzelia genus. Some Mentzelia species have one type or shape of trichome; some have several types. Adonis Blazingstar has two types of trichomes – one is shaped like a grappling hook; one is shaped like a barbed needle. It’s the trichomes that grab on and hold tight. But what possible function do they serve the plant? Surely a leaf sticking to the fur of a passing animal or a person’s pant leg, while decorative, is otherwise pointless?

What Good are Mentzelia Trichomes?

Like plant hairs, trichomes aid a plant in water conservation in times of drought by reducing transpiration, and in situations of other environmental stressors, such as excessive UV light and extreme temperatures. The trichomes serve as a protective barrier between the leaf, stem, or other part of the plant, and the environment.

Trichomes can function as water collection, retention and funneling structures during a rainstorm.

The grab-and-hold nature of trichomes when they attach to fur or clothing can cause enough vibration of mature seed capsules to shake loose seeds ready for dispersal.

Trichomes are the plant’s primary defense against herbivory; not from livestock or rodents intent on munching leaves, but from insects that attempt crawling amongst the grappling hooks and barbed needles intent on causing damage. As can be seen in electron microscope images, insects have been photographed speared and hooked and killed because they were unable to escape their entrapment by trichomes.

But not all insects succumb to the fate of trichomes. Aphids are able to navigate the dense forest of hooks and needles without capture, allowing them to wreak havoc on vulnerable and tasty leaves, stems and seed capsules.

And that’s why the Mentzelia genus of the Stickleaf family is one of the natural curiosities of the plant kingdom. Maybe now, you too, are Hooked on Trichomes?

I hope you’ve enjoyed this post, and do thank you for stopping by!

And if you’re curious about how Trichomes contribute to the enjoyment and/or medicinal benefits of marijuana (Cannabis sativa), here’s what I found:

Trichomes are the primary site for cannabinoid production (i.e. compounds like THC & CBD responsible for the plant’s psychoactive/therapeutic effects.

Trichomes are the site of terpene production which gives different Cannabis strains their unique aromas/flavors.

Trichomes are the site of flavonoids known for antioxidant and medicinal properties.

A Quirk of Nature: Fourwing Saltbush

November 25, 2024

In November 2023, I created a journal page of seeds and seed pods, which posted on 12/14/2023, under the title November Littles: Seeds, Pods, Silk, and Wings. On that page was a small drawing of two Fourwing Saltbush seeds, absent any information about this plant species, Atriplex canescens. At that time I remember finding a wealth of articles and research documents about this widespread shrub, but what really stuck in my mind was a very unusual quirk exhibited by this plant. Finally, a year later and WOW! I discovered Fourwing Saltbush has a reproductive superpower …… this species has the ability to change sex!

An Unusual Quirk

My first dive into the literature revealed that within a 7-year period of time, 40% of a Fourwing population switches sexes with 20% of a population changing sex every year. Botanically, this is known as Trioecious, or the 3rd Sexual State.

But clearly a bit of back peddling is needed ……. if Trioecious is the 3rd Sexual State in plants, what about the 1st and 2nd sexual states, huh? Yes, they exist …….. but before explaining them, which requires comparison with the more common sexual state in plants, I must describe this sexual norm.

And now for a little Botany 101 ……..

The Sexual Norm …… Plants with Perfect or Complete Flowers

You are likely familiar with plants like roses, tulips, lilies, garden strawberries, beans, peas and cabbage. If you’ve closely examined their flowers while inhaling their fragrant aromas, you may have noticed their centers have both female and male parts. These are known as plants with Perfect or Complete flowers (aka hermaphroditic or bisexual) defined by each individual flower having a fully functional pistil (the female part) and stamens (the male parts). Worldwide, about 90% of flowering plants have Perfect or Complete flowers.

Monoecious ….. the 1st Sexual State

Here again you are likely familiar with many plant species described as Monoecious (moh-NEE-shuhs). These include corn, all of the plants in the gourd family (i.e. cucumber, squash, watermelon), oak, birch, pine, spruce and dogwood. Monoecious, which means “one house” in Greek, describes plants having separate female and male flowers in different places on the same plant, often blooming at different times. Visualize corn growing in a field; the tassels are the male (staminate) flowers, and the corn kernels you eat are the female (pistillate) flowers. Around 10% of all flowering plant species worldwide are Monoecious.

Not to confuse the matter, but sometimes botanical experts refer to Monoecious species as Perfect or Complete because they have both male and female flowers on the same plant, even though these flowers are separate and considered sexually Incomplete (aka unisexual) by themselves.

Dioecious ….. the 2nd Sexual State

A plant species with individual plants in a population having only female flowers, and individual plants of the same species in the same population with only male flowers is called Dioecious (dahy-EE-shuhs). This Greek word meaning “two houses,” describes plants such as spinach, asparagus, sumac, currant, box elder, willow, holly, ginkgo, juniper and aspen. Only 5% of all flowering plant species worldwide are Dioecious.

Another confusing matter once again. There are botanical experts that refer to plant species with Perfect or Complete flowers as Dioecious because they require cross-pollination to produce seeds (fruit). Tree fruit species such as apples, pears, cherries and plums are common examples.

Trioecious ….. the 3rd Sexual State

An extremely rare reproductive strategy among flowering plants, Trioecious (aka trimonoecious or “three houses”), is characterized by a species that can have Incomplete (unisexual) male, Incomplete (unisexual) female, and Perfect or Complete (bisexual or hermaphroditic) male/female flowers on separate plants in a population or even all on the same plant! Just over 3% flowering plant species worldwide are Trioecious (trahy-EE-shuhs).

This is where Fourwing Saltbush (Atriplex canescens) enters the story

Primarily a Dioecious species, some Fourwing Saltbush populations have a Monoecious component ranging from entirely male (staminate) or female (pistillate) individuals to those that are Perfect or Complete (hermaphroditic or bisexual). And in this Dioecious–Monoecious–Hermaphroditic gender system, referred to as Trioecy, switching sexes occurs. To reiterate from an earlier paragraph, on average, in a 7-year period, about 40% of a Fourwing Saltbush population switches sexes with 20% changing from male to female or from female to male every year.

Reasons Behind and Benefits of Fourwing’s Sex Change Phenomenon

Fourwing Saltbush has evolved to be one of the most adaptable plant species found throughout central and the western US. It grows from sea level to 8500 feet elevation, and in a multitude habitats within a wide range of plant communities, no matter the successional stage. Fourwing can adapt to all soil textures, soil depths and all but the wettest of soil conditions. The species is able to tolerate hot (+100F) and dry (6” precipitation annually) summers, and bitter cold (-50F) and dry winters.

The ability of the species to adapt to such a wide range of physical and climatic conditions is, in part, due to this sex change phenomenon. Environmental stressors seem to be the major triggers resulting in Fourwing plants switching sexes. Female plants are more likely to change sex than male plants, especially following a drought, an extremely cold winter, or after a heavy fruiting season. Because fourwing is so tasty as range forage, overgrazing can also trigger a sex change, with male plants tending to dominate regularly grazed sites. Male plants that change to female typically flower earlier than plants that remain female season after season. And female plants dominate richer sites than do male plants, becoming larger and producing more seed.

Undoubtably there’s more environmental stressors, such as wildfire and other climate change-induced factors, that may result in Fourwing Saltbush to switch sex. I’ll be curious to learn what they are and how these triggers influence the adaptability and survivability of this robust species. And I’m excited get busy marking this season’s female and male plants that we see nearly every day, and will begin more closely observing these populations for gender changes and possible stressors that may have triggered these switches.

A Retrospective and Thoughts on Prospective Studies

There’s so much to learn about Fourwing Saltbush that it seemed logical to tackle one characteristic at a time. Originally I had planned to discuss both the plant’s reproductive quirk and several of its common galls, but found there would be too much information for one post. While deciphering the complexities of the Fourwing’s sex change abilities, I found it necessary to describe certain key botanical terms in my buildup to the crucial piece of the puzzle ….. the Trioecious reproductive strategy. So this post focused on the first of my two journal pages; my beginning exploration into this plant. The galls illustrated on my second journal page, that could not be easily chopped away from the first page, serve as a preview of a future post about the fascinating Fourwing Saltbush.

And Finally ……….

For a shrub I used to describe as a messy tangle of branches haphazardly cloaked with unremarkable features like dusty little grey-green leaves, nearly invisible flowers, shreddy dull grey trunks and a chaotic canopy, Fourwing Saltbush has captured my imagination, respect, and love as an almost invincible survivor of our changing world!

Hopefully you found this interesting and informative. Bet you never look at flowering plants in casual ways again. Let me know if you are familiar with Fourwing Saltbush. Where does it grow? Have you ever marveled at the thousands of winged seeds densely crowded at the tops of these shrubs? And then satisfied an irresistible urge to strip dozens of skinny branches of those ripe seeds, tossing them in the air like confetti? If so, please share.

As always, thanks for stopping by!