By Emily Humphreys, the Eli Kirk Price Plant Science Fellow


9:50 AM

My day started with an accidental decapitation. Blades whirred above me, and time seemed to slow. Thwack! Thwack! Thwack! The plant I was holding recoiled with each impact. A streak of light green fell to the floor.

In hindsight, I really should have seen it coming. The plant I am studying, Virginia Mallow (Ripariosida hermaphrodita) can grow up to sixteen feet tall in a single season. Combine this with a green house full of ceiling fans and you have a recipe for disaster.

I took a moment to collect myself, then inspected the damage. Half a leaf and a cluster of wilted flowers lay curled on the floor. I breathed a sigh of relief. Being so late in the season, the plant has only a handful of buds left to bloom. Those are what I am interested in. Wilted flowers we can stand to lose.

Tonight, I am going to bring the Virginia Mallow home and then, tomorrow, I will begin recording observations of the plant's floral development. Each day I will monitor things like whether the flower is releasing pollen and if the female reproductive organs are visible. Then, when I look across my notes from the month, I will have a good understanding of the timing of floral events in this particular plant.


A white flower with five petals stands out on a blurry background. A hand is holding the flower up for the camera.
Virginia Mallow (Ripariosida hermaphrodita). This is one of my research flowers!
Credit: Emily Humphreys

 10:05 AM

I just realized I never introduced myself. My name is Emily, and I am the 2022-2023 Eli Kirk Price Plant Science Fellow at the Morris Arboretum. This means I get to spend my days trying to answer fascinating questions about plants. Right now, I am investigating floral development, but past fellows have investigated everything from which environments certain plants prefer to bias in botanical collecting. Over the next few months, I will be writing a series of blog posts on different aspects of plant science at the Arboretum. I hope you will come along for the ride.

10:50 AM

I am back from an unexpected but delightful tangent in my day. As I was writing, two other members of the Plant Science department, Dr. Tim Block (Director of Plant Science) and Nora Wildberg (curatorial intern), walked in with armfuls of grasses—they had everything from stout green grasses, to sprawling purple grasses, to grasses with lemon yellow anthers that they had gathered from natural lands. Dr. Block, an expert on the flora of Pennsylvania, led Nora and I through the twisting branching series of diverging paths that is grass identification. Half an hour later, and after more than one wrong turn, we had identified purpletop, a beautiful native Pennsylvania grass with a voluminous tuft of eggplant purple inflorescences.

The photo shows Nora sitting in the lab looking intently into a microscope. She’s holding dissection tools.Here’s Nora looking at a grass under the microscope. Sometimes traits that are too small to see without magnification are essential for plant ID.
Credit: Emily Humphreys
A highly magnified grass inflorescence sits in a circular frame. Fuzzy purple stigmas and large brown anthers spill out of the spikey green flowers.Under a microscope, you can appreciate Switchgrass’ (Panicum virgatum) rosy purple stigmas.
Credit: Nora Wildberg

11:51 AM

The weather today is beautiful. It rained nonstop the last two days much to the delight of our horticulture staff. Today is sunny, but the rain has taken the edge off the summer heat.

I am sitting outside on a wall behind Gates Hall, the building where I work. I am certainly biased, but this is one of my favorite spots in the whole Arboretum. Two large dogwoods give shade and there is a little fountain here that is home to two bright green frogs. There used to be only one frog, but his diligent and dashing croaking won him a pair. Watching their love story has been one of the highlights of my summer.

I have spent the last hour working on a Virginia Mallow time lapse. I figured out how to create them yesterday after some online reading and a bit of trial and error. Now it is one of my favorite things to do. Time lapses are a fantastic way to visualize floral changes. I am hoping I can capture some of the phenomenon I observed during my research this summer.

Still, it turns out that making time lapses is not as engaging as you might think. Once you set up the camera, it does most of the work. Which leaves me sitting on this wall, enjoying the sunshine, and writing to you.


A large green frog sits on the edge of a small man-made pool.
Meet the Gates Hall frog.
Credit: Emily Humphreys


1:32 PM

It turns out the time lapse I created was out of focus. Not very out of focus, but when you are trying to look at individual grains of pollen, it does not take much to ruin the shot. The time lapse also had bursts of overexposure as the sun came out from behind clouds. Now, two hours older and wiser, I find myself back on the same wall while my camera takes shot after shot. Fingers crossed this one is a bit more usable.

2:50 PM

Success! The second time lapse was a major improvement. Next, I want to try taking a time lapse through a microscope, but that is a project for a different day.

I am planning to spend the rest of the afternoon on a handful of dull but important tasks; there is a series of instructional videos on how to avoid phishing scams sitting in my “to watch” folder. As such, I think I will wrap up my first post here.


Like most days at the Arboretum, today was filled with small pieces of big projects. Daily floral observations mean little on their own, but they create a picture over the course of months. Time lapses illustrate that picture, and opportunities for learning expand the scope of future possibilities. I have only been at the Morris Arboretum for a few months, but I am already beginning to see projects come together and maybe even the possibility to discover something new.




By Nora Wildberg, John J. Willaman & Martha Haas Valentine Curatorial Intern

Welcome to the September issue of the What’s in Bloom blog at the Morris Arboretum! Recent heavy rain storms have been a welcomed end to this summer’s drought, and although the peak flowering season has passed, there are still lots of beautiful blooms to appreciate in our gardens. A number of the plants highlighted this month are located in the Arboretum’s natural areas, meadows, and wetlands, teeming with life and color as we ease out of summer and into fall. From large white hibiscus flowers to the tiny flowers of a single grass spikelet, there is still so much to enjoy and look forward to this coming season.


Goldenrod (Solidago canadensis) growing at the Morris Arboretum.



Solidago canadensis
Solidago gigantea

The meadows at the Arboretum are bearing a bright, warm yellow hue as native goldenrod blooms. Small flower clusters arranged in a pyramidal shape crown these six-foot-tall stalks. A member of the Aster family, goldenrod blooms consist of many tiny flowers—what appears to be one flower emerging out of a bud are actually a number of small florets. S. canadensis and S. gigantea are two of the goldenrod species currently in bloom. Try to find both of these in the meadows: S. canadensis has hairy leaves and stem, while S. gigantea is smooth. 







New York ironweed (Vernonia noveboracensis)



New York ironweed
Vernonia noveboracensis

Among the goldenrod in the meadows is this other beautiful native wildflower, its wide-spreading larger purple flowers complementing the tiny upright yellow blooms of the goldenrods. Another member of the Aster family, ironweed has similar flower structure to goldenrod, with each purple bloom consisting of many small florets.









Wood grass (Sorghastrum nutans)



Wood grass
Sorghastrum nutans

A more inconspicuous bloom hidden in the bold colors of the meadows are the flowers from this native warm-season grass. Growing up to five feet tall, wood grass is a staple of the vast prairies that once covered central North America. The flowering stalk is topped with light brown spikelets in a feathery branched arrangement known as a panicle. Emerging from each spikelet are two white stigmas and several bright yellow anthers which collect and produce pollen, respectively. There are several other grass species currently blooming in the meadows, each with varying spikelet arrangement and color. Switchgrass (Panicum virgatum), for example, has a wider panicle with green spikelets bearing purple stigmas and orange anthers.







Swamp rose mallow (<em>Hibiscus moscheutos</em>) 


Swamp rose mallow
Hibiscus moscheutos

Visible from the main entrance drive, the large white blooms of this native hibiscus dot the Arboretum’s wetland at this time of year. Look inside, and you’ll notice that each flower has a dark crimson center. Although swamp rose mallow blooms are only open a couple days, each plant will open new flowers until early fall, attracting lots of valuable pollinators to the wetland.







Monkshood (<em>Aconitum sinomontanum</em>)



Aconitum sinomontanum

Native to China, this plant bears unique flowers as we near the end of summer. Walking along the path from the Widener Visitor Center to Out on a Limb, you’ll notice clusters of small purple flowers brightening this shady area of the garden. Each flower has a distinctive cupped upper petal known as a galea, which in Latin directly translates to “helmet.” Another name for monkshood is wolfsbane—members of the genus Aconitum contain the toxin aconitine, which may have historically been used to poison wolves.







Bougainvillea golden-rain-tree (Koelreuteria bipinnata)



Bougainvillea golden-rain-tree
Koelreuteria bipinnata

Tucked behind the parking lot by the top of the Orange Balustrade, this tree is a bright pop of color in the gardens this month. Branched clusters of small yellow flowers decorate these wide-spreading trees, whose delicate flower petals will soon fall and leave a carpet of yellow on the ground, hence the name golden-rain-tree. If you can, observe the individual flowers and notice their lovely fragrance and distinctive red color at the base of each petal.








Spider flower



Spider flower
Cleome spp.

This fun flower gets its name from its many long, spindly stamens (male reproductive organs) that shoot out from each inflorescence. Located throughout the Rose Garden, these tall, brightly-colored flowers beautifully complement the roses that are still blooming—they even have little prickles along their stems! These plants will continue to bloom until it frosts, adding consistent visual interest to the gardens long after peak blooming season is over.








Nora Wildberg received her bachelor’s degree in Art and Archaeology from Princeton University in 2021, focusing her studies on museology. Having previously worked with an ancient coin collection, she now works directly with the Morris Arboretum’s living collection assisting in the preservation and record-keeping of our woody plants. In recent years, she developed a passion for plants and nature, and in her free time, she enjoys birdwatching, painting, hiking, and looking at art.




Written by Caroline Mertz
Photos by Ryan Drake

<em>Impatiens pallida</em> (pale jewelweed)A pinned sunflower bee (Svastra obliqua).
Credit: Ryan Drake


Have you noticed a blue vane trap hanging around the Morris Arboretum? It's part of the Pennsylvania Bee Monitoring Program, which studies regional bee diversity across the state. The decline in populations worldwide has called attention to better understand the diversity, distribution, and abundance of wild bee pollinators.

The bee monitoring program uses three different trapping techniques in order to catch the widest variety of bee species. The blue vane trap hangs two to three feet from the ground, attracting bees with its bright blue color. Nine plastic bowls painted either white, blue, or yellow are laid on the ground in a transect, closer to the populations of ground nesting bees, which make up over 70% of Pennsylvania's bee populations. The final trapping technique is netting, where monitors use butterfly nets to catch any other unique bees they can find in the area. These techniques combined aim to allow monitors to observe the fullest range of wild bee species in an area so they can track changes in population sizes and biodiversity in Pennsylvania.

Blue vane trap at the Morris Arboretum.The blue vane trap hangs two to three feet from the ground, attracting bees with its bright blue color.
A woman trapping bees in a net.The final trapping technique is netting, where monitors use butterfly nets to catch any other unique bees they can find in the area. Shown here is Caroline Mertz, the Hay Honey Farm Natural Areas Intern. 
Bees in a dish being identified and sorted.Sorting and identifying collected bees.
Bees being pinned and studied. Pinning bees.
<em>Impatiens capensis</em> leaf at the Morris ArboretumLong-horned bee (Melissodes denticulatus, female).

If you didn't get a chance to experience the Morris Arboretum from the high up on a swing, you're in luck—by popular demand, Summer of Swings has been extended through October 2! Admire the changing leaves, learn about Galilieo's Law of the Pendulum, and play our HIGH SPY activity to explore your surroundings and discover something new!

Thanks to everyone who entered the Summer of Swings Photo Contest. We received an astounding amount of entries, and we're so impressed with the talent and creativity our visitors expressed from both behind and in front of the camera.

We are so pleased to announce Elizabeth Encarnacion as the winner! Her photo hits all the marks: originality, a unique view of the Arboretum, and the joy of swings. Congratulations, Elizabeth—we look forward to featuring your photo on our website and seeing you at the Arboretum with your prize membership!

Two children playing on a swing at the Morris Arboretum.