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Hunt family donation links Botanic Gardens to pre-flood neighborhood

1-20-2021 Jessie Berta-Thompson 

A version of this article first appeared in the January 2021 issue of the Redstone Review.

The Rocky Mountain Botanic Gardens has a beautiful, new red sandstone bench, thanks to a generous donation by Mary Hunt. From 1994 to 2008, Mary and her late husband Don Hunt were residents of the Foothills Mobile Home Park, on the land where the Gardens are now. This gift is a bridge between the land’s history as a neighborhood and its new, post-flood life as a public garden. The Rocky Mountain Botanic Gardens is an outdoor space in Lyons dedicated to enjoying and learning about native Colorado plants, taking root between 4th Ave. and Highway 7 and between Prospect St. and the South St. Vrain Creek.

The Hunt bench. Photo by Linda Talley.

The Hunts first lived in Lyons from 1974-1978, when they lived on Riverbend Trl. Ct. Don owned and ran a laundromat on High Street called the Wash House, and Mary worked at Longmont United Hospital. Then they moved to Longmont but returned to Lyons when they retired. The Hunts enjoyed life by the river from their home that was located by the current entrance and patio of the Gardens. Don Hunt passed away in 2012. Mary Hunt now lives in Longmont. 

Garima Fairfax, longtime Lyons resident and the Gardens Board of Directors president, recalls how the Hunts “had a beautiful flower garden surrounding their mobile home, with colorful irises that Don generously dug up to share with friends and passersby.” The bench has an iris engraved on it, to honor him with his favorite flower. After filling their yard with plants, Mary Hunt says, “Don ran out of room, so he farmed the other side of the alley, too.” Their garden had a pond full of fish and blooming water lilies, as well as masses of bright tulips in spring. 

Don Hunt, at left, by his garden, with his brother Gene, right. 

At the time of the September 2013 flood, the plot of land where the Gardens is now was home to at least 37 residents in 13 mobile homes, two cabins and one house, according to a kind examination of records by Lyons Town Administrator Victoria Simonsen. These structures were mostly destroyed in the flood, and the people were displaced. At the time, Mary and Don’s grandson Joshua and his wife Kelly were living in the Hunts’ former home there. The land is now town property, part of a flood recovery buyout program for high flood-risk sites, leased to the Gardens. 

Foothills Mobile Home Park as it looked on after the flood on February 15, 2014. Photo by Cathy Rivers.

Come spring, there will be flowers blooming around the Hunt bench. Last fall, garden volunteers planted Rocky Mountain iris (Iris missouriensis) there, as another tribute to Don and Mary’s garden. This iris is our local native species, also known as western blue flag, and it grows wild throughout the western United States. You might see it blooming in wet meadows on your spring rambles. It is elegant, purple-blue, and a bit smaller than typical garden irises. For interested local gardeners, it’s commercially available and hardy. Lacy dark veins on the flower form nectar guides that direct pollinators to just the right spot, while also making the flowers even more beautiful to human eyes. 

The Gardens Board of Directors would like to extend a warm thanks to Mary for her generosity and support of our efforts to create a garden on the spot of her old home. Cathy Rivers, talented designer and Gardens volunteer, created the bench design. Western Stone Company made the bench. A group of the Lyons Volunteers led by Rick DiSalvo installed it between snows last month. Future visitors will now have a nice spot to sit, surrounded by native grasses and wildflowers in the Prairie section of the Garden, and an important part of the land’s history will be remembered.

Mary Hunt visiting the Garden, with volunteers, September 15, 2020. Photo courtesy Sharon Denton.

Junipers! Bright berries and scent bring cheer to winter walks

12-29-2020 Jessie Berta-Thompson 

A version of this article first appeared in the December 2020 issue of the Redstone Review.

As other plants fade into winter, the evergreens stand out in our landscape, like the lovely Rocky Mountain juniper (Juniperus scopulorum). It grows as incredibly hardy lone tufts in the dry, exposed prairie-foothills transition zone along Highway 36. It grows as perfect topiary mushrooms carved by deer hungry enough to eat its tough, spicy foliage in winter. And it grows as elegant teardrop trees shimmering with blue fruit and songbirds tucked within. Up close, twirling a twig or crushing a blue berry-like cone in the fingers releases their intense, distinctive, delicious fragrance. 


These small, shrubby trees are members of the Cypress family, which is full of interesting evergreen conifers including cedars, arborvitae, cypresses, and redwoods. The leaves of the Rocky Mountain juniper are tiny overlapping scales pressed flat against the twigs. In juvenile plants, and in some growing parts of older plants, the leaves are instead sharp, very pointy spikes that protect against nibbling from herbivores. The tree’s bark is sometimes flaky, sometimes shredded into fibrous strips. Its small cones are fused into a closed seed-carrying case, making them look more like berries. This species is native to the western United States and Canada, favoring dry, rocky hillsides, often mixed with other trees. Nighthawk trail at Hall Ranch has some beautiful, mature examples within the first mile that are a joy to behold and to sniff. All sorts of wildflowers grow tucked in their shelter, and wildlife nestles in, too. Mammals and many birds eat juniper berries – waxwings, solitaires, turkeys, and robins to name a few. The dense branching structure of the Rocky Mountain juniper provides nesting and roosting sites, especially useful in winter when cover options are slim.


We have another species of juniper locally, the common juniper (Juniperus communis). This plant grows in a wildly different way, forming dense mats low to the ground. Its leaves are all sharp spikes with little white stripes. Its berry-like cones are larger and darker, but with a similar crisp scent. It’s easily spotted in the forests of Rocky Mountain National Park. The distribution of this species is vast, growing at high Northern latitudes around the globe. Peoples across the Northern hemisphere have enjoyed its scent, flavor, and medicinal properties through time. 


Walking along, it’s striking to see how some junipers are covered with berries, while others have none, giving plants very different colors when viewed from afar. Rocky Mountain junipers generally have separate male and female plants – males bear yellowish brown pollen-bearing cones at their twig tips in spring, while female plants carry the berries. The plants set larger crops of berries once every 3-5 years, adding even more to their variability in the landscape. Looking closely at the berry-like cones, you might notice that some are different colors. Rocky Mountain juniper cones are pollinated in the spring, grow to full size by fall, but don’t fully ripen until the following fall, and don’t fall off the plants until the spring after that. The plants carry both this year’s and last year’s berries at the same time. Over the full 2 years they take to reach maturity, the cones change from green to pale blue, to deeper blue as their whitish coating wears off. In some places, if you peer into the branches of a juniper, you might see weird, knobbly yellow twigs growing. This is the juniper mistletoe (Phoradendron juniperinum). It’s a hemiparasitic plant adapted to live off junipers that steals its host plant’s nutrients but can also do some photosynthesis itself. Other conifers have their own specialized mistletoe species. 


Looking around at our landscape this particular winter, what happens to Rocky Mountain junipers after a fire? Their small size, structure of dense growth, and thin bark offers little protection and easy opportunities for deadly fires, compared to larger trees like ponderosas. The largest Rocky Mountain junipers can survive some fire, but smaller plants cannot. Unlike many native shrubs, they don’t regrow from rootstock after the above-ground part of the tree burns. Instead, they will regenerate from seed, relying on animal dispersal to repopulate burned areas over the coming years. Rocky Mountain junipers grow slowly, but they live a very long time, often to 250-300 years, with a few reported cases of more than a thousand years.


Tough and versatile, junipers are often planted for their ornamental and wildlife value as well as in windbreaks.  Local nurseries carry both the native species and cultivated varieties selected for different shapes, colors, and textures. At the Rocky Mountain Botanic Gardens in Lyons, we’ve planted Rocky Mountain junipers and another beautiful species found in southern Colorado, the one-seeded juniper (Juniperus monosperma). Next spring, we’ll add spreading mats of common juniper to the Montane garden, under evergreen trees and interspersed with mountain wildflowers, and look forward to the day they set seed.


Much of the information in this piece was gathered from the US Forest Service Fire Effects Information system website, a good place to learn about plants and their relationships to fire https://www.feis-crs.org/feis/Photos above were taken by the author 12-10-20 along the Picture Rock Trail at Heil Valley Ranch in Lyons, showing Rocky Mountain junipers.


What’s in bloom this week at the Rocky Mountain Botanic Gardens?



7-17-20 Jessie Berta-Thompson, Photos by Zach Berta-Thompson


The Plant:

Sunflower (Helianthus annuus), Sunflower family (Asteraceae)


After rising steadily upwards for a months, the sunflowers at the Rocky Mountain Botanic Gardens have burst open. Visible at the front of the gardens, these plants appeared all on their own, and, because pretty much everyone loves a sunflower, we left most in place, weeding and planting around them. These plants are most likely the wild sunflower, Helianthus annuus, also called the common or annual sunflower, though, given their self-starting nature, their full background is mysterious. The sunflower has the unusual distinction of being a high-value crop, a pesky weed, or a native wildflower, depending on context.


Wild sunflowers are large, branching plants in the Sunflower or Aster family (Asteraceae) with multiple blossoms each about 5 inches across. The flower heads have bright yellow petals and chocolate-brown centers. The centers are made up of tiny flowers that flash yellow pollen when they bloom, starting in a ring around the outside of the disk then moving inwards. This plant grows to impressive heights of 8-10 feet - a few of the ones at the RMBG are close to that. The stems and leaves are covered with bristly hairs. In fall, each flower head becomes laden with seeds, which, although smaller than the sunflower seeds bred for people to eat, attract diverse birds. Sunflowers grow in open, sunny, often disturbed places across North America. Wandering around Lyons, you might see wild sunflowers along roadsides, in the St. Vrain flood restoration sites, or in gardens where they’ve hopped a fence.


There’s an idea that the sunflower is named for the flower’s habit of following the sun over its course through the sky, but in fact this plant’s relationship to the sun is a bit more complicated. The unopened flower buds, leaves and stalks of young plants do indeed display light tracking behavior, called phototropism (turning to light) or heliotropism (turning to the sun). The primary purpose of leaves, generally, is to collect energy from the sun. The tilting of sunflower leaves allows them to maximize light collection throughout the day, fuelling their rapid, vigorous growth. By the time the plant is mature and the flowers open, the flowers no longer move. Open flowers tend to be fixed mostly facing east. The effect in farmed fields, thousands of flowers all facing the same way, is stunning.


The sunflower is not the only tall, yellow flower in the West, but it’s brown flower centers distinguish it from many other yellow-centered, yellow-petalled flowers, and few similar plants get quite so big. The close relative prairie sunflower (Helianthus petiolaris) can be identified by its more branching growth habit, splitting into multiple branches near the ground, and by its narrow, elongated leafy bracts on the back of the flower head, instead of the rounded, tear-drop shaped ones on the wild sunflower. Incidentally, these bracts, called phyllaries or involucral bracts, are one of the distinctive features of the Sunflower family, used by the plants to protect the developing flower heads and by people to tell species apart. The species name of the wild sunflower, annuus, refers to the fact that this plant is an annual plant, living for just one year - sprouting, growing, flowering and setting seed to make next year’s plants, within the span of a year. Many other sunflowers are perennials, living for multiple years, like the garden favorite Maximilian sunflower (Helianthus maximilianus), which is native to slightly wetter prairies east of the Front Range, or the Jerusalem artichoke (Helianthus tuberosus), which is grown for its edible tubers as well as its flowers.  Hiking around Lyons, the little sunflower (Helianthus pumilis) is often encountered, growing 1-3 feet tall, with sand-paper-like rough leaves and yellow flower centers. Plans for planting in the Riparian section of the RMBG include the tall marsh sunflower (Helianthus nuttallii), which grows along Colorado’s ditches, streams, marshy meadows and ponds. 


Sunflowers have been cultivated by people for thousands of years. Sunflower seeds significantly larger than wild ones, indicating domestication, have been found in North American archaeological sites dating to as far back as 2800 BCE. Across ancient America, sunflowers were planted and selectively bred for food, oil, medicine, cosmetics and dye. The seeds were key source of dietary fat, ground-up into a nutritious staple. The Hopi people bred varieties still cultivated today with dark seeds that make a rich purple dye. Now, sunflowers are grown at large scales primarily for cooking oil, but also for birdseed, human snacks and floristry. In 2019, 59,000 acres of Colorado were planted with sunflowers, based on surveys by the USDA Natural Agricultural Statistics Service. Compared to their wild relatives, cultivated sunflowers mostly have larger flower heads (1 foot across), grow taller (up to 20 ft), and have just one flower on a single stalk instead of branching. Hopping back and forth between continents, much of the modern breeding of commercial oil sunflowers took place in 18th and 19th century Russia, at least partly because religious restrictions on cooking oils didn't cover this newly arrived plant. The many varieties of sunflowers now grown by farmers, florists and gardeners have continued to be bred, on the more practical side, for seed size, nutrition, disease resistance and oil content, and on the more whimsical side, for shockingly large plant size, conveniently small plant size, extra petals, and color, from burgundy to pale lemon.


For kids and gardeners looking for things to do among pandemic-limited options, sunflowers offer all kinds of botanical fun. Because they grow so tall so fast, it can be satisfying to measure sunflower plants’ growth over time, with daily or weekly measurements, careful record-keeping, and plots of time vs. height made with graph paper, spreadsheet software, or code. Along the way, you can also make friendly bets on if and when a plant will surpass each person’s own height. On a shorter time scale, try to catch the plant’s daily heliotropic movement, by talking about how a plant looks at breakfast and dinner, by taking before and after photos, or by giving up a smartphone for a day to capture a time-lapse movie. In fall, observe what kinds of animals visit to eat seeds, dissect a drying flower head to search for seeds, and save a few in home-made artistic seed packets for planting next year. At any time of year, sunflower seeds sold for sprouting can be planted in a windowsill or patio pot for the thrill of seeing large, quick-to-germinate, tasty seedlings emerge, while providing another opportunity for quantitative exploration, like counting the number of sprouts visible each day or duct-taping a ruler to the planter for easy height tracking.

To grow sunflowers at home, choose from the vast variety in seed racks and catalogs (they grow best from seed and like full sun), look for the perennial relatives as plants at nurseries, or, if you live around Lyons, just wait and they’ll come. If you’re interested in this selective weeding approach, sunflower seedlings have pointy, rough-feeling leaves that fan out around a center stalk. Enjoy the sunflowers this summer!


To learn more about the sunflower take a look here:



And for its history, here:



What’s in bloom this week at the Rocky Mountain Botanic Gardens?

Mexican hat


7/5/2020 Jessie Berta-Thompson, Photos by Zachory Berta-Thompson


The Plant:

Mexican hat (Ratibida columnifera), Aster family (Asteraceae)


A brilliant dash of yellow has appeared at the Rocky Mountain Botanical Garden, shooting upwards from small mounds of muted green foliage among the mulch and rocks – it’s Mexican hat (Ratbida columnifera), also known as prairie coneflower, currently in full bloom. At long last, the garden has plants, intentionally planted, with signs, including this one. At the inaugural volunteer planting session on June 23, 284 plants of 18 different kinds were triumphantly tucked into place in the Prairie Grasslands section of the garden.


Anthea Rice, highly accomplished professional garden designer and RMBG board member, designed the Prairie Grasslands garden to capture the beauty of our native western prairie ecosystem and inspire garden visitors and home gardeners. It is situated at the front of the property, where passersby are most likely to see it. At the entrance, bright colorful flowers, showy shrubs and striking grasses welcome visitors into the garden (or they will after they’ve grown in a bit). Moving deeper into the design, some areas are planted for combined beauty and educational impact in clusters with identifying signs, and other areas are planted to recreate the meadow-like mix of plants as they grow in the wild.


The grasslands of Colorado are called short-grass prairie, to differentiate from wetter tall-grass prairie ecosystems farther east. The short-grass expanse once extended from the base of the foothills to the eastern edge of the state and beyond. Water is scarce in this landscape, and shrubs and trees are absent, yet a healthy prairie supports a high diversity of plants and animals, historically including the iconic bison, pronghorn and prairie dog. Small parcels of wild prairie have survived between other dominant land uses, wherever they were protected, ignored or restored. If midday summer heat is avoided, these can make for fascinating walks, photo safaris and botanical excursions, often overlooked in favor of glamorous mountain experiences.


Our recent prairie planting effort included more than a dozen Mexican hat plants, prairie natives that will continue to bloom all summer long. Mexican hat flowers have downward-tilting petals below an elongated column at the center that sticks straight up. The tilt of the petals gives each flower its hat or cone-like shape, and its names. Our plants have pure yellow petals, but other varieties are deep red or a combination of the two. The center column of the flower changes over time, starting pale green. Over time, a brown ring charges up from the base to fill the column, made up of tiny flowers opening and maturing. This plant’s leaves are deeply lobed, pointy and covered with small hairs, and the whole plant grows to be 1-3 feet tall. Beyond the garden, Mexican hat can be found in prairie grasslands, restoration sites, roadsides and open meadows in the foothills. It grows across much of North America, most commonly found on the Great Plains. There are a few relatives with similar flowers, like the short prairie coneflower (Ratibida tagetes), which has a smaller, rounder center and shorter flower stems, growing in the southeastern part of the state, and the gray-headed prairie coneflower (Ratibida pinnata), which grows farther east and forms larger plants, 3-5 feet, a tall-grass prairie plant. Our Mexican hat plant (Ratibida columnifera) is sometimes called upright prairie coneflower to differentiate from these others. 


Mexican hat is in the Aster family (Asteraceae), also called the Sunflower family, or the Composite family (Compositae). This is one of the most diverse plant families, containing upwards of 25,000 species and about 10% of plant species on the planet. The family includes artichokes and lettuce in the kitchen, local weeds dandelion, chicory, thistles and salsify, and native wildflowers yarrow, blanket flower, different thistles and pearly everlast. The Aster family is characterized by compound flowers – each apparent blossom is made up of many tiny flowers, like those visible in the changing column of Mexican hat. Each individual seed is the product of one of these tiny flowers. The flowers in the disk-like center of a sunflower or the central spike of the Mexican hat are called disk flowers. The flowers carrying the large petals are called ray flowers, attracting pollinators from a distance. Different Aster family members have different arrangements of ray and disk flowers, creating a wide variety of forms.

Like many of the wildflowers of the Great Plains, Mexican hat has a rich history of human use. The Native American Ethnobotany Database, a curated collection of plant uses with documented sources, contains a long and varied list of many tribes’ applications for this plant. The Cheyenne used decoctions of this plant’s leaves and stems to relieve pain, to treat poison ivy rashes, and on rattlesnake bites. The Dakota used the flowers to treat wounds and the leaves to make a hot beverage. The Zuni used an infusion of the whole plant as an emetic. Women of the Western Keres crushed its leaves to encourage weaning. These are just a few examples of what people have done with this plant that was widely valued as medicine and also used as dye and food.


Horticulturally speaking, Mexican hat would make a lovely addition to any local garden, for its low water demand, long-lasting summer blossoms, and the food it provides for pollinators and seed-nibbling birds. It’s a perennial, and the yellow, burgundy and bicolored variants are available as plants from native-plant friendly nurseries or as seed. Planting Mexican hat can be a small tribute to the plant’s history on the landscape and its ancient peoples, and in even the smallest pocket of a backyard it might bring a vision of the prairies that once stretched a thousand miles east.


To learn more about Prairie Coneflower, and how to grow it, take a look here:


What’s been in bloom lately at the Rocky Mountain Botanic Gardens?
Tall penstemon

June 25, 2020 Jessie Berta-Thompson

The plant
Tall penstemon, Penstemon virgatus var. asa-grayi (synonym Penstemon unilateralis), Plantain family, Plantaginaceae (formerly Figwort family, Scrophulariaceae)

There’s been a surprise growing at the gardens in the past few weeks. What started out as few notes of lilac color in the meadow-like area at the back of the garden grew to an orchestral swell of penstemon flower spikes. Last year, our gardeners worked in this part of the garden to remove the most serious weeds
and cut back overgrown material, but otherwise the land was left to its own devices. Delighted by this plant’s unexpected abundance, a few of us spent some time with magnifying glasses and books to figure out what it was. To the best of our abilities, we came up with this stunner most likely being tall penstemon (Penstemon virgatus var. asa-grayi as well as the synonym Penstemon unilateralis). This plant is also called upland blue beardtongue, upright blue beardtongue, wandbloom penstemon, one-sided penstemon, and beardless sidebells penstemon. Where did it come from? We didn’t plant it, but it could easily have hopped the highway or river from a population in the foothills, or perhaps past human wildflower lovers helped it move into town. This plant is common up and down the Front Range. Its distribution map cuts a wide north-south path through the middle of the state, growing in grassy habitats, on rocky hills, and, father south, among the pinyon-juniper forests. This plant also grows in Wyoming and New Mexico.

Tall penstemon blossoms are various shades of light purple, with delicate lines marking the way to the paler interior. Like many penstemon species, the flower color varies quite a bit from plant to plant, pinker to bluer and darker to lighter. The flowers are shaped like bells or tubes, splitting into 5 petal lobes, with two lobes at the top and three at the bottom. Its pollen is borne on 4 stamens that curve around the inside of the blossom like a ribcage, and there’s a fifth sterile stamen called a staminode (characteristic of penstemons), which can be seen running up the base of the flower tube. Larger pollinators that make it into the flower for nectar get an automatic dose of pollen from the stamens curving over the flower entrance, acting like spring-loaded back-scratchers. As its name suggests, this plant is tall for a penstemon, typically growing to 20-60 centimeters or sometimes as high as 1 meter. Penstemon seeds are produced in capsules that split open when ripe, revealing little cups full of small, irregular seeds.

Telling this plant apart from its relatives came down to size (big), how the flowers all point in about the same direction, the absence of hairs (many other penstemons have small hairs on the flowers, leaves, or stems), the shape of the anthers (the pollen-holding structures, which are in pairs opposite each other), and the shape and color of the leaves (narrow, green). For example, in the plains and foothills around Lyons, another very similar penstemon is commonly seen. Called the one-sided (again) or sidebells penstemon (Penstemon secundiflorus), this plant also has one-sided flower spikes, with an overlapping color spectrum of pale pink to purple flowers. However, it has a fuzzy yellow staminode - the bearded tongue that gives the penstemons their name beardtongues - while the tall penstemon has a plain white hairless staminode, a difference visible with a quick peek into a flower. The one-sided penstemon’s leaves are also paler, wider and juicier. Both are very nice to come across, regardless of identification.

As it turns out, there are a lot of different kinds of penstemons. In Colorado alone, there are about 56 penstemon species of growing wild, based on the species described in the comprehensive 2015 book, ‘Flora of Colorado’ by Jennifer Ackerfield. Of these, 9 species are endemic to Colorado, meaning they are native to and found only in the state. To preserve this remarkable diversity in the face of habitat loss, two of these endemic penstemons are on the Federal Endangered Species list (Penland’s penstemon, Penstemon penlandii, listed as endangered and Parachute penstemon, Penstemon debilis listed as threatened). The designs for planting in the botanical gardens include 7 of the more common penstemons. The tall penstemon that we already know likes growing on the RMBG plot will be intentionally planted in the labeled beds, along with the low or bluemist penstemon (P. virens), one-sided penstemon (P. secundiflorus), dusky penstemon (P. whippleanus), Palmer’s penstemon (P. palmeri), firecracker penstemon (P. eatonii), and Rocky Mountain penstemon (P. strictus). Together, they should display a good range of the variety found in the world of penstemons.

Penstemons are in the Plaintain family (Plantaginaceae), named for the European medicinal plant that’s now a common North American weed. This family includes foxgloves, veronicas, and the high elevation tundra plant alpine kittentails (Besseya alpina). However, for many years, penstemons were classified in the Figwort family, Scrophulariaceae, as older field guides will attest. The re-assortment of Figwort family members came about when DNA sequencing began to help evolutionary biologists untangle the relationships between species in a more direct way than older methods, which were based largely on flower details and other mostly visual features of plants.

Penstemons are widely enjoyed, as wildflowers encountered on hikes and as gorgeous, pollinator-sustaining garden plants. Many varieties are available for planting, both native species and cultivars bred to new combinations of size and color. Purple, white, and blue penstemons, including the tall penstemon, are
primarily (but not exclusively) pollinated by bees and a specialized pollen wasp, Pseudomasaris vespoides. This wasp visits many penstemons, including rare and endangered ones that really need their pollinators, and it rarely stings, although it bears a menacing resemblance to yellow jackets. The purple-white-blue penstemons generally have flowers that are sturdy and fixed horizontally to support the weight of these insects while they work. Red, orange, and pink penstemons are more adapted for pollination by hummingbirds, though insects visit them, too. In addition to the color, some red-orange-pink penstemons have evolved downward facing, narrower, longer tubes that hummingbirds can comfortably hover below.

In other, very important, RMBG news, a 400-foot irrigation tube has been installed, and planting has begun! The first planting day was Tuesday, June 23, when volunteers worked to tuck many flowers, grasses, and shrubs into the Prairie Grasslands Garden. The plants are here! And for a bit more about Tall Penstemon take a look here: http://beta.floranorthamerica.org/Penstemon_virgatus_var._asa-grayi

What’s in bloom this week at the Rocky Mountain Botanic Gardens?

Black locust


6/11/2020 Jessie Berta-Thompson, photos by Zach Berta-Thompson


Plant in bloom:

Black locust, Robinia pseudoacacia, Legume family, Fabaceae


High above the beds of the RMBG, several of the old trees that were glumly leafless all spring have finally sent out their leaves and, what’s more, exploded into bloom. These trees are black locusts, currently festooned with large, drooping clusters of fragrant flowers.

Black locust flowers are white, occasionally tinged with pink, with a small streak of yellow up close. The tree has compound leaves, meaning each leaf is made up of multiple leaflets attached to a single leaf stem, in this case, 7-21 thin oval leaflets branching off to feathery effect. The black locust’s species name pseudoacacia and another of its common names, false acacia, refer to the similarity of its leaves to those of the acacia tree. On new shoots and twigs, a pair of short, stout thorns appear at the base of each compound leaf. The mature bark forms deep furrows and ridges that separate and rejoin as they wind up the trunk, giving it a woven or knitted look. Flat, brown pods from last year, 2-6 inches longs, are visible on the branches, and dark seeds, like little beans, still cling to some. 

Black locusts can also spread by sending up new growth from roots to form clonal thickets. Black locusts are fast growing and relatively short-lived trees, typically lasting around 60 years and occasionally living up to 100 years. The flowers produce abundant nectar beloved by pollinators, and, by extension, beekeepers, who particularly value the delicate flavor of black locust honey (sold as acacia honey in some places).


There are a few other kinds of locusts planted along the Front Range that occasionally escape their gardens. The New Mexico locust, Robinia neomexicana, is native to the Southwest (southern Colorado, but not here), has pink flowers, hairy seed pods, and grows more as a shrub than a tree. The honey locust, Gleditsia triacanthos, has yellow-green flowers, smaller leaflets, an even number of leaflets on each leaf compared to black locust’s odd number, larger seed pods, and branching thorns. The Bristly locust, Robinia hispida, can be differentiated by its pink flowers and very hairy stems.


Locust trees are in the legume or pea family (Fabaceae), and so are peas, beans, acacias, lupines, and wisteria, with its similar drooping flower clusters. Another legume family member, purple prairie clover, Dalea purpurea, is slated for planting in our Prairie Grasslands garden soon. This family is known for its symbiosis with nitrogen-fixing bacteria. These bacteria live in specialized nodules on the roots of legumes and perform a powerful and costly chemical reaction to turn inert nitrogen gas from the air (which is made up of 78% nitrogen gas) into ammonia, a form of nitrogen that plants can use. The bacteria are fed with plant sugars, the plant receives a key nutrient, and the process adds more total bioavailable nitrogen to the ecosystem, enriching the soil and helping other plants.

Black locusts originally come from the central Appalachian Mountains and the Ozarks, evolving on lush mountainsides. They are useful, beautiful, and adaptable trees and so have been widely planted all over the country and the world for centuries. The genus name, Robinia, refers to Jean and Vespasien Robin, a father-son team of botanist-gardener-herbalists credited with planting the first black locusts in France in the 17th century. Black locusts are planted for apiculture, for their wood, as ornamentals, to provide quick-growing shade, and for erosion control. Two major pests, the locust borer and locust leaf miner, sometimes work against these goals.


In many places, the black locust has escaped cultivation. In Colorado, it is spreading out around old farms and towns and creeping up riparian corridors and ditches. It can cause problems by crowding out other plants, sucking up limited water resources, forming hard-to-remove dense thorny thickets, poisoning livestock (it can make a toxin related to ricin), and facilitating co-invasion by noxious weeds that ride its nitrogen wave into new habitats. However, the same traits that make it a weed in some contexts – fast-growing and tolerant of lousy conditions – also make it a valued restoration plant, used for reclamation of heavily damaged mining sites.


Among the reasons people have planted the black locust so widely is its close-grained wood, which is hard, dense, and strong. The tree is sometimes called the post locust, because the wood is so useful for fence posts, durable and resisting rot in soil contact. It’s been used for tool handles, furniture, ships, mine timbers, and railroad ties. I didn’t expect my reading on the flower that caught my eye this week to come up with anything like this, but, because of its hardness, black locust wood was also used for making police batons in the late 19th century. Known as locust clubs, at the time they caused terror and controversy about the nature of tools and tactics used by police, so sadly resonant with today.


To see this species and reflect on its history, the black locust trees at the RMBG are visible from the river path between Bohn Park and the Labyrinth by Route 7. An evening stroll is best to appreciate the scent. They are some of the tallest trees in the garden, with some bare, dead branches, likely indicating senescence or disease. It’s also worth finding a shorter tree to enjoy the flowers and insect activity at eye level. There are many black locusts, of all ages and growth forms, up and down the St. Vrain.


A particularly stunning specimen can be seen behind a dumpster on Park Dr. near the Lyons Town Hall. This tree is the representative for its species in the Lyons Walking Arboretum, a collection of trees with identifying signs paired with a walking tour map and illustrated guide. The Lyons Walking Arboretum was created as a joint project of the Town of Lyons Ecology Advisory Board and the RMBG, transforming trees already present in town into a toolkit for botanical education and appreciation. Get the map and guide (link below) and take a stroll, mindful of the trees that have been planted in Lyons over the years.


To learn more about the black locust, take a look here:



For a map and guide to the trees of the Lyons Walking Arboretum see here:


What’s in bloom this week at the Rocky Mountain Botanic Gardens?

White Campion


6/1/2020 Jessie Berta-Thompson & the RMBG

A version of this article first appeared in the Lyons Recorder.


Plant in bloom:

White Campion, Silene latifolia, Pink family, Carophyllaceae


The bright bulbous blossoms of white campion have popped out this week, along the river trail and behind the garden compost pile (which is getting very large from all the weeding that’s been going on lately). The most distinctive part of a white campion flower is the calyx behind the petals, which inflates balloon-like around the developing seed capsule and is decorated with green or purple-red veins. A calyx (plural, calyces) is the structure that protects a flower bud. After a flower opens, the calyx on many species looks like a set of small petal-like leaves or leaf-like petals (known as sepals) at the base of a flower, but the calyx of white campion is prominent and fused into one piece. Each flower also has five white petals with deep notches nearly splitting them in half, and there’s a little extra frill of a collar at the flower’s center. The plants are hairy, which makes new leaves soft to the touch and the calyces, already striking at a distance, look even wilder under a magnifying lens. This plant is a Eurasian native, introduced and now widespread across North America. In typical weedy fashion, it grows on roadsides, floodplains, disturbed areas, meadows, and cultivated land.

In the heat of midday, white campion often looks crumpled. That’s because these flowers bloom at night to attract moths as pollinators. They also release their fragrance at night. Certain other white flowers do this, too, so gardeners sometimes plant collections of fragrant white night-blooming flowers to enjoy after dark. The RMBG Prairie Grasslands garden (slated to be planted first) will include two species of native evening primroses, the prairie evening primrose, Oenothera albicaulis, and the white stemless evening primrose, Oenothera caespitosa. Like white campion, these flowers open in the evening, as their names suggest. Both grow low to the ground with stunning, large white flowers pollinated by night-flying insects.


Up close, white campion flowers don’t all look the same. This species is dioecious – each plant has either male or female flowers. This is one of the mechanisms plants have evolved to avoid self-fertilization and excessive inbreeding, increasing the flow of genetic material by requiring two parent plants for every seed. The flowers on male plants have bright clumps of yellow pollen at the center, while female flowers have a cluster of curving white structures to catch the pollen. Only the fruit-bearing female flowers have the ballooning calyces. On males they are still noticeable but don’t puff up. Another dioecious species among local favorites is the rocky mountain juniper (Juniperus scopulorum). Some plants bear juniper berries while others produce pollen-spewing male cones that give the plants a brownish-yellow look in spring.


White campion is in the Pink family (Caryophyllaceae), named for the flowers called pinks, which are also known as dianthus and often are actually pink. Carnations and sweet Williams are other cultivated members of this family. Colorado native Pink family species include the prairie mouse-ear, Cerastium arvense, which forms constellations of white flowers under ponderosas in spring, and the pink cushion-forming alpine favorite, moss campion, Silene acaulis. At first glance, two other Pink family members introduced from Europe can look like white campion. Bladder campion, Silene vulgaris, has even larger bladders (calyces) that lack the dramatic veins of white campion, and bouncingbet or soapwort, Saponaria officinalis, has petals without the deep notch, a slender calyx, and hairless leaves. Bouncingbet and white campion were both used historically as soap, their roots beaten to a lather for laundry. Keep an eye out for white campion blooming around town all summer long – it’s certainly a plant worth a closer look, but don’t expect to see it (much) in our lovingly weeded native garden beds.


In other garden news this week, our partners at the Town of Lyons have just completed the work for the garden to get irrigation water. Although we’re planning to use as little water as possible, watering will be necessary for establishing young plants. This brings us one step closer to planting!


To learn more about white campion take a look here:


What’s in bloom this week at the Rocky Mountain Botanic Gardens?



May 25, 2020 Jessie Berta-Thompson & the RMBG


Plant in bloom:

Chokecherry, Prunus virginiana var. melanocarpa, Rose family, Rosaceae


Throughout the month of May, Lyons has been full of flowering chokecherries (Prunus virginiana var. melanocarpa). The chokecherry is related to the cherry, and the choke part is about the bitterness of the fruits. It’s also called wild cherry, bird cherry, and chuckleyplum. This lovely shrub is recognizable by its elongated, drooping white flower clusters. Flowers are set against bright green leaves, which have tiny teeth along their edges and are widest slightly above the middle of the leaf, useful for telling it apart from other local cherry relatives, wild plum (Prunus americana) and pin cherry (Prunus pensylvanica), when there aren’t fruits and flowers around. The bark on young branches is dark with pale spots called lenticels, which are pores that allow gas exchange through bark. In Colorado, chokecherries usually grow into shrubby thickets, but in rich, wet conditions they can become small trees. The blossoms are starting to fade in Lyons, but they can still be spotted at higher elevations through June.


The sweet-scented flowers of the chokecherry are a great, abundant early resource for bees and other pollinators. Soon, clusters of little round fruits will start to ripen, going from green, to red, to black. Chokecherries are beloved by birds, bears, and many other animals, who eat the fruits then disperse their seeds far and wide. People eat them, too, sweetened in jams, in sour craft beers, or straight off the bush, avoiding the toxic pit. Indigenous tribes developed many culinary preparations for chokecherries, including some that neutralized the seed’s toxins, and used many parts of the plant for medicine and dyes. The fruits make a purple-red dye, and the inner bark and leaves make green.


The chokecherry is a stone fruit, forming a group of close relatives along with cherry, peach, plum, and apricot, all sharing hard pits and attractive spring blossoms. In addition to the chokecherry, we’re looking forward to planting two other stone fruits native to Colorado in the RMBG, the sand cherry (Prunus pumila var. besseyi) and the wild plum (Prunus americana). These plants are all in the diverse Rose family (Rosaceae), which includes roses, raspberries, and the native shrubs bitterbrush (Purshia tridentata) and mountain mahogany (Cercocarpus montanus).


The chokecherry is found throughout North America, but our local variety, with deep black berries, is native to the West. It grows in gulches, along hillsides, and especially near streams and rivers. Its bigger, greener leaves stand out among foothills shrubs, and they turn yellow in fall. Along the St. Vrain, chokecherries have been included in flood restoration plantings, a healthy part of a riparian ecosystem, controlling erosion and feeding wildlife.  At the RMBG, there are mature chokecherries growing around the margins and little clumps shooting up in the beds, all on their own. They didn’t self-plant exactly where we wanted them, so we’ll have to plant a few more in the Riparian garden, where we’ll be showing off the lusher side of Colorado plant life.

Photos taken by Zach Berta-Thompson along the St. Vrain in Bohn Park, May 22, 2020

What’s in bloom this week at the Rocky Mountain Botanic Gardens?

Blue mustard


5/20/2020 Jessie Berta-Thompson & the RMBG

A version of this article first appeared in the Lyons Recorder.


Plant in bloom:

Blue mustard, Chorispora tenella, Mustard family, Brassicaceae


After years of work by our passionate plant lovers to create a native plant garden in Lyons, the RMBG is a maze of gravel paths and tidy mulch, almost ready for planting! Right now, the garden is closed to let worms, fungi, arthropods, and microbes build up the soil undisturbed. These critters are busily composting the cardboard and wood chips covering the surface of the beds to make rich soil. Meanwhile, human volunteers are pulling weeds and continuing soil preparation. The planting and the opening of the gardens are expected midsummer. When that happens, we’ll use this space to share what’s going on at the gardens, botanically speaking, and to share our love of local plants.


Since there’s nothing officially planted in the gardens yet, it’s a bit early to be talking about what’s blooming there, but there are actually lots of flowers – on the weeds.  In the RMBG and all over Lyons, the rather lovely and tenacious weed known as blue mustard (Chorispora tenella) is currently in full bloom.

Also known as crossflower, musk mustard, or purple mustard, this plant has pale purple, slightly wrinkly, 4-petalled, x-shaped flowers, and the leaves have a distinctive odor. It’s an annual plant that forms upward curving pods, plump with next year’s weed seeds. Up close, the leaves, stems, and pods have tiny hairs. This plant is an introduced species, native to Eurasia but now found in many Western and Midwestern states. It can form dense carpets of purple haze along roadsides.

Blue mustard is a member of the mustard family (Brassicaceae), which includes the spice in the yellow bottle, cruciferous veggies like broccoli, kale, and Brussels sprouts, and many native wildflowers, including Western wallflower (Erysimum capitatum) and Front Range twinpod (Physaria bellii). Blue mustard is just one of many early-blooming mustard family weeds that infest and/or grace local disturbed areas in spring.


Keep an eye out for blue mustard around town and in your yards, enjoy the early color it brings, then consider pulling it up to make more room for our native plants. We’ll keep weeding at RMBG to get ready for the many flowers to come.


To learn more about Blue Mustard take a look here:


December 2018

posted Dec 19, 2018, 1:42 PM by Deirdre Daly

Garima Fairfax, president of the board of directors, presented to the Town of Lyons Board of Trustees at their December 17, 2018 meeting. Garima was accompanied by members of the Rocky Mountain Botanic Gardens (RMBG) board and other supporters of the Botanic Gardens. The Trustees indicated their approval of the project and directed the RMBG board to complete the application for license to use the property for the Gardens. A copy of Garima's presentation is attached here for anyone who may be interested.

The next step is to begin to weed the property in preparation for the Gardens. If you're able to help, we'd love to have you! Please contact Garima at garima@rmbg.org or complete the form on the About Us/Contact Us page.

Spring 2018 update!

posted Apr 27, 2018, 5:02 PM by Toshen

As the Town of Lyons continues to recover from the 2013 flood, a number of properties have become available through the Dr. BOP (Deed-Restricted Buy-Out Properties) program. The Rocky Mountain Botanic Gardens group was asked by the town staff to choose which parcel would best fit our purpose, and to then give a presentation to the Town Board of Trustees.

We chose the lot in the confluence that used to be the mobile home park, near the corner of 4th Ave and Prospect St. We presented our proposal, found everyone in favor, and are now drawing up our budget and timeline. When the town approves that, we then ask for approval from FEMA.

We are very excited about this location for the future botanic gardens of Lyons, the very first in Boulder County. It is 1.26 acres adjacent to both the South St. Vrain River and the nearly completed Bohn Park, and is walking distance from downtown Lyons. The nearby neighbors we've spoken with are very happy with our plans.

The members of our volunteer group are Anthea Rice, Kris Todd, Garima Fairfax, Dianne Andrews, Carter Christenson, and Deirdre Daly. We also have 25 volunteers who are enthusiastic to help build the display gardens. If you'd like to be added to our email list of volunteers, please contact Garima: garima@rmbg.org

We plan to begin on the lower part of the parcel, and to divide this area into the natural ecosystems of Colorado: foothills, prairie grassland, montane, riparian (plants that grow along rivers), and plants that grow in the southwest part of Colorado. We'll have pathways meandering through the display gardens, and visitors can learn the names of local plants they see while out hiking, or find new local plants they would like to have in their gardens. Native plants do well in a garden situation, and need less water and fertilizer than cultivated plants. 

The garden will also be a place to view native birds and butterflies from a bench along the path, or to come and do watercolor paintings of native flowers. Our annual plant sale every May supports the creation of this educational garden. 

See the Our gardens page for an updated drawing of the gardens.

Not Now, Deer

posted Jan 13, 2013, 11:09 AM by Garima Fairfax   [ updated Dec 12, 2018, 11:34 AM by Deirdre Daly ]

by Garima Fairfax 

I just found a book called DEERPROOFING YOUR YARD & GARDEN by Rhonda Massingham Hart. It starts with eye-opening facts about deer that help you understand their perspective, as well as their strengths and their beauty, and their incredible senses of smell, hearing, sight, and survival.

You can read about every type of deer deterrent, from fencing to rattling scarecrows to foul smelling rotten egg sprays (homemade or store bought), complete with all the pros and cons of each. As an example, you might have heard that scented bars of soap hanging from trees can deter deer from feasting on tasty garden flowers and greens. But did you know that it takes 450 bars of soap per acre to be effective? And that these same bars of soap can actually attract rodents?

Well, maybe after reading all of that, you want to try planting known deer-resistant plants. Here are a few that I have personal experience with that do well in and around Lyons, Colorado. (The book includes every area of the country.) If your garden is near a natural area, be especially careful to plant only native plants, OR if you plant non-native plants, chose only non-invasive species.

Birch   (Betula spp.)
Catalpa   (Catalpa spp.)
Douglas Fir   (Pseudotsuga menziesii)
Spruce   (Picea spp.)

Forsythia   (Forsythia spp.)
Juniper   (Juniperus spp.)
Lilac    (Syringa vulgare)
Oregon Grape   (Mahonia spp.)
Spirea   (Spirea spp.)

Ajuga   (Ajuga spp.)
Snow-in-summer   (Cerastium spp.)
Thyme   (Thymus spp.)
Wild Strawberry   (Fragaria spp.)

Clematis   (Clematis spp.)
Grape   (Vitis spp.)
Trumpet Creeper   (Campsis radicans)
Virginia Creeper   (Parthenocissus quinquefolia)
Wisteria   (Wisteria sinensis)

Daffodil   (Narcissus spp.)
Grape Hyacinth   (Muscari spp.)

Cosmos   (Cosmos bipinnatus)
Marigold   (Tagetes spp.)
Poppy   (Papaver spp.)
Salvia   (Salvia spp.)
Snapdragon   (Antirrhinum spp.)
Sunflower   (Helianthus spp.)
Sweet Alyssum    (Lobularia maritima)

Beardtongue   (Penstemon spp.)
Beebalm   (Monarda spp.)
Blanketflower   (Gaillardia spp.)
Black-eyed Susan   (Rudbeckia spp.)
Cinquefoil   (Potentilla spp.)
Columbine   (Aquilegia spp.)
Coreopsis   (Coreopsis spp.)
Gentian   (Gentiana spp.)
Iris   (Iris spp.)
Lupine   (Lupinus spp.)
Phlox (Phlox spp.)
Poppy   (Papaver spp.)
Russian Sage   (Perovskia atriplicifolia)
Santolina   (Santolina spp.)
Violet   (Viola spp.)
Wild Buckwheat   (Eriogonum spp.)

Catmint   (Nepeta x faassenii)
Chives   (Allium schoenoprasum)
Coneflower   (Echinacea spp.)
Hyssop   (Hyssopus officinalis)
Lavender   (Lavandula spp.)
Mints   (Mentha spp.)
Oregano (Origanum vulgare)
Sage, garden   (Salvia officinalis)
Thyme   (Thymus spp.)
Yarrow   (Achillea spp.)

Some of these stronger smelling herbs like sage and thyme can be planted amongst other plants in your garden that deer are eating, to help cover up their appeal and deter deer from dining there.

I highly recommend this book if deer are an issue in your garden and you want to learn more.

Hart, Rhonda Massingham, 2005, Deerproofing Your Yard & Garden, Storey Publishing, MA.

The Common Juniper

posted Jan 13, 2013, 10:42 AM by Garima Fairfax   [ updated Jan 13, 2013, 10:45 AM ]

We have in our woods here in Colorado a prostrate juniper called Common Juniper (Juniperus communis subsp. alpina). Less than 3 feet high, it forms a low, spreading clump. You’ve probably seen this coniferous undershrub in our forests, but you may not be aware of how common it really is. It turns out that it is the most widely distributed conifer in the world, and the only circumpolar conifer in the northern hemisphere. That’s enough to warrant a closer look.

This Common Juniper is an evergreen shrub with short, sharp needles, with female or male cones generally on separate plants. The female cone scales are fused together to look like round berries, green at first, then ripening to a dark blue with a grayish “bloom” or coating. The male cones are very small, and can be found at the tips of the branches while they form pollen. After they release their pollen, they disintegrate.

The female berries are an important source of food for birds and small mammals in our woods, and have a long history of medicinal use by Native Americans coast to coast, Europeans, and Northern Asians. This low, spreading juniper, which is found sprawling under Ponderosa Pines of the foothills and all the way up to Bristlecone Pines in the subalpine, proves itself to be a valuable and adaptable member of our ecosystem.

  • Benedict, Audrey DeLella. 2008. The Naturalist’s Guide to the Rockies: Colorado, Southern Wyoming, and New Mexico. Fulcrum Publishing, Golden, Colorado. 
  • Kershaw, Linda; MacKinnon, Andy, and Pojar, Jim. 1998. Plants of the Rocky Mountains. Lone Pine Press, Canada.
  • Lanner, Ronald M. 1999. Conifers of California. Cachuma Press, Los Olivos, California. 
  • Weber, William A. 2001. Colorado Flora: Eastern Slope. 3rd ed. Univ. of Colorado Press, Niwot, Colorado.

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