The other day I noticed this Oregon ash tree. It had mostly fallen over last year in the ice storm and was blocking part of the road through the arboretum. The company that helped clean up cut off the part obstructing the road and left the rest. Last year the tree sent out a massive amount of sprouts, which I want to try and count, I just haven't gotten around to it yet. Oregon ash is unbelievably vigorous at sending out new growth if it is cut back or damaged in a storm. This one reminded me of a spiky caterpillar. I can’t imagine what this tree will look like in 50 years with all of these new limbs and assuredly more storm damage to come during that time. This tree has evolved a tenacious spirit for survival. In writing that last sentence I thought of the emerald ash borer that is on its way. This amazing tree is going to suffer some losses when it arrives. I hope and feel that some of them will endure and reestablish a healthy population in the ecosystem.
Winter Buds
In the winter, there is so much to explore. Now is an excellent time to look at all of the overwintering buds of trees and shrubs. They come in many different shapes, sizes, colors, and textures. If you are allergic to poison oak, it would be good to be familiar with how it looks because you can still get a rash from it in the winter. The winter buds of the cascara tree are not covered by scales, the tiny brown leaves are visible on the stem. I didn’t include the incense cedar because it doesn’t form overwintering buds, the shoot tips stop growing in the fall and resume growth again in the spring (Tollefson, Jennifer E.). Have fun checking out their diversity and see how many you can identify. Happy New Year!
Reference
Tollefson, Jennifer E. 2008. Calocedrus decurrens. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.usda.gov /database/feis/plants/tree/caldec/all.html [2025, January 1].
Douglas-fir Needles and Bud
It was foggy and quiet out at the arboretum today. Walking along the upper meadow, I was struck by the majesty of the Douglas-fir trees shrouded in a white mist. Their needles and the overwintering buds are so beautiful.
The pointed buds are a rich amber color with overlapping resinous scales. They really stand out against the complementary green of the needles.
The needles are .5-1.5 inches long with a blunt tip. They are green above with two white stripes on the underside. The needles are noticeably lighter underneath when you flip the branch over. Their arrangement can vary from nearly flat-lying to radiating uniformly around the twig.
This is probably the most common tree in Oregon because it was planted throughout the state for the economic value of its timber. For me, I like to revisit things in nature that I pass by everyday and renew my wonder. There is always something new to see and experience.
Circuitry Conundrum
I haven’t the slightest idea of how things work, so all I can say is that my computer has been under the weather these days. I am not sure what has been happening, but the synapses inside the brain of this gizmo have been firing so slowly. It seems to be constantly contemplating every little thing I do to the point that writing a post has been pretty much impossible. That said, I was finally able to get this message out to let you know that I have not abandoned my post!
I love the pattern of the vascular system of this Oregon Ash leaf. It’s pulsing with electricity as it manufactures energy from sunlight beaming down on its surface.
Gall Wasps Galore
Check out how many galls are forming on the underside of this oak leaf! They remind me of brightly colored candy sprinkles you would use to decorate a cupcake for a kid’s birthday party.
While holding this leaf up to take a photo, it was noticeably heavy from all these galls and it seemed like it could easily become unattached from the additional weight. The top of the leaf was still dark green, so all of these galls didn’t seem to be affecting the leaf’s ability to photosynthesize.
As you can see, two kinds are forming. The Pinched Leaf Gall Wasp looks like a basket or small pastry pinched shut at the top. They can vary in color from tan to red. The other one is a saucer-shaped gall with a brown bump in the middle. That one is identified as an Undescribed Plate Gall Wasp #8. The galls are small and I imagine the wasps that emerge from them are only a couple of millimeters long.
I took this photo where a few small oak trees are growing along the edge where the forest meets the meadow. Many of these young oaks were adorned with leaf and stem galls. I’m not sure why the wasps chose to lay their eggs on these oaks. For some reason they found this area a more suitable location than the oaks out in the meadow where I saw far fewer.
Coast Redwood Sprouts Erupt From Stump
There is a small grove of Coast Redwood trees at the beginning of the river path in front of the White Oak Pavilion. During the ice storm, two of them sustained significant damage, and they cut them down for safety reasons I suppose. As a survival mechanism, heaps of sprouts have erupted from this stump transforming it into a small shrub.
Two conifers on the West Coast produce sprouts from the base if they are cut down or sustain injury, the Coast Redwood (Sequoia sempervirens) and the Pacific Yew (Taxus brevifolia). A side note, the Pacific Yew is “grouped with the conifers because it has needlelike foliage, its fruit is not a cone. Instead, it’s an aril—a large, single seed surrounded by a soft, fleshy, bright red pulp (Jensen, pg. 58),” which are highly poisonous.
In an article by the Penn State Extension, What Makes Some Tree Species Prolific Stump Sprouters?, it says: “Stump sprouts come about from suppressed dormant buds at the root collar of a tree – the meeting place of the stem and roots – that become active in the case of injury or extreme environmental changes that induce stress. While there are dormant buds that exist all over the tree, sometimes referred to as epicormic buds, they typically have a short lifespan after emergence and give rise to branches, not new stems (trunks). Dormant buds at the root collar, however, have traces all the way to the pith and in some species may live just as long if not longer than the main stem. They formed when the tree first put out roots and shoots.
The dormant buds grow slowly along with the tree; staying near the surface of the living wood beneath the bark. They also are believed to be genetically more juvenile which means that these buds are not necessarily a continuation of the tree's life but more of a revitalization, rebirth.”
If you look on the left side of the shrubby stump, you will see a small trunk that was sprouting from the base of the tree that wasn’t cut down or damaged. You can see in one of the photos below that this small trunk developing doesn’t look to be in that great of condition, but I need to go back and take a closer look at it. I will be interested to see how the sprouts on this stump continue to grow and develop over the next few years. Will they revitalize the already developing small trunk and die off or will one of the sprouts become a trunk and develop into a new tree?
Resources
Jensen, Edward C., et al. Trees to Know in Oregon. Rev. April 2005., Oregon State University, 2005.
What Makes Some Tree Species Prolific Stump Sprouters? https://extension.psu.edu/what-makes-some-tree-species-prolific-stump-sprouters. Accessed 18 Aug. 2024.
Incense Cedar Gall
Amidst the confusion this year of trying to figure out the female flower of an incense cedar tree, I discovered what initially appeared to be a cone developing is actually a gall. I was tipped off that this growth was different because I came across an incense cedar with developing cones. I immediately realized that they were not the same.
I was walking around with a friend at the arboretum and we decided to cut one of these growths open and see what it was like inside. When we cut it in half, it was fleshy and green inside, and there wasn’t an insect or larva inside. Thinking that there had to be something inside, we cut one of the halves in half to further investigate. We found a tiny, metallic green wasp cradled inside! I mean this insect was tiny. I took a heap of photos to try and show it to you. They mostly turned out fuzzy because the insect was so small. I couldn’t zoom in close and get a photo with decent resolution. The one below is the best one of them.
I am fascinated by the world of galls, how they form, the variation of their colors and shapes, and the diversity of wasps. It is such a mysterious world to me. It seems like a whole other level of awareness to tune into these tiny creatures and observe their life cycle. It reminds me that there is a vast universe of life unfolding right before me of which I am mostly unaware.
I posted about a small, orange caterpillar I found at the tip of one of the branches in January (Incense Cedar Branch Tip Mystery) that I thought was one of the female flowers. Maybe these two phenomena are connected.
Hair-Stalk-Gall Wasp
Lately, I have been keeping an eye out for galls, and this is a good time of year to find them. Many gall wasps use the Oregon white oak as their host, so if you want to go hunting for galls, this is a great place to start. Many things in nature are small, especially insects like gall wasps. And honestly, I can’t identify any of the gall wasps themselves, mostly because they are so small and I haven’t spent much time trying to find them. That said, I am getting more into it and starting by finding the weird and wonderful galls created to house and protect these tiny insects as they begin their lives.
Recently, I found this tiny gall growing from an oak leaf and matched it with the hair-stalk-gall wasp found in Ronald Russo’s book Plant Galls of the Western United States. This gall grows along the margins of leaves and forms a smooth, pointed gall that grows from a thin stalk. In spring, the color of the gall starts from yellow to orange and turns beige by summer.
In his book, Russo writes, “These smooth galls are fully developed by April, with males and females emerging between April and June. Galls remain on host leaves until fall, even though the occupants have left. This would appear to be the bisexual generation of an as yet undescribed unisexual, summer-fall generation with its own distinct gall. Common.” Gall wasps are tricky. It appears that its summer-fall generation has not been observed or recorded. It’s fascinating that the second part of the yearly lifecycle of a common gall I can find at the arboretum, is still a mystery. There is so much to discover in our backyards!
Note: I want to go back and take better photos, which I hopefully can do this week, and update these.
Resource
Russo, Ronald A. Plant Galls of the Western United States. Princeton University Press, 2021.
Oak Apple Gall
Looking at August Jackson’s pamphlet Oak Gall Wasps of Mount Pisgah I find the California gall wasp (Andricus quercuscalifornicus). He describes it as “Very large, tan, ball-shaped galls on young twigs. Often remaining on twigs for a few years.” I have heard these referred to as oak apple galls and some of them certainly look like the color and shape of an apple as they begin to form. They are easy to find out at the arboretum.
I have been reading a book called The Nature of Oaks by Douglas W. Tallamy, and I just read this part of the book that talks about gall wasps. I decided to quote part of what he wrote in the book to make sure that the information was correctly passed on to you. I found this so unbelievably fascinating. Check it out.
“Most cynipid species, particularly those associated with oaks, have a complicated life history known as alternation of generations. The first generation is comprised entirely of parthenogenetic females—that is, females that can lay fertile eggs without mating with a male. That’s a handy trait to have because there are no males in this first generation. The adults and galls produced by the first generation have a morphology specific to each species. The second generation, in contrast, produces adults and galls that are entirely different from those of the first generation, and instead of just females, it yields both males and females that need to mate in the usual way to produce viable eggs. For the longest time, cynipid taxonomists thought the two generations were two different species, and you can hardly blame them; the cynipids in each generation looked entirely different from each other, as did their galls. I’m still not sure how, without the aid of the DNA analysis, taxonomists ever figured out that the wasps that looked one way in April and another way in June—and which produced vastly different galls—both belonged to the same species.
The diversity in gall size and shape is astonishing. I suppose it shouldn’t be, though; gall morphology is unique to each species, and most of the nearly 800 North American cynipids make two kinds of galls. That’s a lot of gall variation!”
Resource
Tallamy, Douglas W. The Nature of Oaks: The Rich Ecology of Our Most Essential Native Trees. Timber Press, 2021, page 61.
Oregon White Oak Male Flowers
The male flowers aren’t as subtle as the female flowers but they do blend into the spring green that is sprouting throughout the landscape. The male flowers are a yellowish green and hang on a thin catkin. The catkin emerges from the tree fairly compact. As it elongates the clusters of stamens spread out, open to release their pollen, and look wispy and light as they blow in the wind.
The male and female flowers are on separate inflorescences on the same tree. Oak trees are wind-pollinated.
Oregon White Oak Female Flowers
Walking into Mt. Pisgah Arboretum you are greeted by the iconic Oregon White Oak and it is the logo of the arboretum. This beautiful, mighty tree is vital to creating a diverse ecosystem and produces nutritious acorns which are a food source for many animals. When the acorns are ripe, jays can be seen carrying them off in every direction to cache them for the winter.
We all know acorns, and I will often hear children refer to oak trees as acorn trees. That said, I imagine that most people are not as familiar with the female flower that gives rise to this nutritious nut. I am here to introduce you to this tiny flower that can easily be overlooked. They grow from the axils (where the leaf stalk meets the stem) of the new leaves. The Washington State Native Plant Society describes the flowers as: “The pistillate flowers grow singly or clustered. Each pistillate flower is surrounded by a scaly, cup-like involucre, contains an inferior ovary and 3 styles.”
Okay. I see the small acorn flower. What I can’t find described or mentioned is the red-tipped appendage that is growing up from the base next to the flower. It seems like it is part of the flower in some way, but I haven’t found any reference to it in any of my research, so far. There is only one, even if it is a pair or a cluster of three flowers. What is that structure and how does it fit in?
The last three photos below show small acorns forming. I took the photos of them last year on May 30.
I hope you are enjoying spring and are finding time to get out and explore.
Reference
Quercus Garryana Var. Garryana. https://www.wnps.org/native-plant-directory/232-quercus-garryana-var-garryana. Accessed 15 Apr. 2024.
Bigleaf Maple Flowers
Bigleaf maples have small, yellow-green flowers with short stalks. The flowers grow in a cluster that hangs downward like a pendant as it develops. Interestingly, bigleaf maples have two mating types. As the flower clusters emerge and start blooming, the initial flowers that open on the first type of tree are female; on the second type, it is the males. As the cluster grows, the male flowers will begin to emerge on the female flower clusters, and the females will start to develop and open on the male flower clusters. Each tree contains both male and female flowers, making it monoecious.
These flowers are a great nectar and pollen source for insects. As I took these photos, the blossoms were buzzing with activity. Male and female flowers both produce nectar, so pollination occurs as the insects move between the two types.
Beekeepers who have honeybees love it when warm, sunny weather coincides with the blooming of bigleaf maple trees. A strong colony of bees can produce enough honey to harvest some in the spring. To my tastebuds, honey made from the nectar of bigleaf maple trees has a distinctive peach flavor. It’s yummy!
Nature is an inexhaustible source of wonder. I look forward to seeing you out there.
Resource
Wagner, David H., A Lane County Almanac. Northwest Botanical Institute, 2021.
Cottonwood Leaves Uncurling
It is spring, and the cottonwood leaves are awakening from the quiet repose of winter. The warmth of the sun kindles their dreams, bursting their flaming sheaths. The combustion releases a syrupy aroma that flows and eddies in air currents along the river. Its swirling fragrance is a calming dizziness. The leaves erupt into an untamed bouquet and ripple outwards like the water they so love. Their bodies will uncurl into ovate blades to scoop up the sun. They will dance and collide in the wind, circulating a song of water in the blue sky of summer. I am looking forward to luminous July days and sitting in the shade of the cottonwood tree. I will uncurl my toes in the water and watch the waxwings swing between the trees over the river.
Cottonwood Branch Sprouting
I was back poking around the river again. I saw this small log lying on the ground and decided to turn it over to see if anything cool was hiding underneath. To my surprise, I saw a branch from one of the fallen cottonwood trees that had started to sprout roots. The log had been deposited there from the river swollen from recent rains. The moist, dark conditions under the log were perfect for sprouting new roots. I imagine that most water-loving trees and shrubs that grow along streams, ponds, marshes, etc., have evolved to sprout new roots from limbs easily.
Cottonwood Explorations
The black cottonwoods sustained considerable damage during the recent ice storm and thousands of limbs that broke off during the storm are lying on the ground along the river. It is heartbreaking to see all the damage, but there is one fortunate side to this story. Some of the trees that fell over still have some roots in the ground which supply enough nutrients to keep them growing. As spring arrived, these trees sent out the male and female flower catkins. This is a great opportunity to see the flowers up close which are normally out of reach on the tree where you can’t easily view them. Black cottonwoods are dioecious, meaning the male and female flowers are on separate trees.
The female flower is interesting. The most obvious feature is the curvy, fleshy, yellow parts projecting out of the top which I interpreted as the stigma that receives the pollen. I took a photo of it drying out and turning brown which gave me a better understanding of its shape. Underneath this is a green, fuzzy capsule that is firm to the touch. I cut one in half to look inside. The walls were thick and a bundle of seeds were nestled inside. This capsule will become brown, split open, and release small seeds with white, fluffy parachutes. When the seeds are being let go it looks like snow blowing around through the air.
The males have 40 - 60 stamens that start as small, red pods. The catkin will continue to grow and elongate. Upon maturity, the red pods split open and release small dust clouds of yellow pollen.
Nature is an inexhaustible source of wonder. I look forward to seeing you out there.
Big Leaf Maple Bark
I love the young bark of bigleaf maples. The green and white stripes on the surface are broken and cracked creating a beautiful pattern that reminds me of the skin of a watermelon.
The young stems of trees can be green and it is usually in the beginning of growth. From my observation, this can last for years before the bark thickens and starts to turn gray or brown in most trees. The stem pictured here is a sprout growing from the base of a big leaf maple, and I estimated it to be around seven years old or more. According to the Oregon Wood Innovation Center of Oregon State University, a bigleaf maple can reach 300 years of age, so I count this as still beginning growth.
Chlorophyll is the green pigment, present in all green plants that is responsible for the absorption of light to provide energy for photosynthesis. So I imagine that the stem of this tree can photosynthesize. I wonder if photosynthesis in young stems occurs just as much in the winter when the stems aren’t mostly covered in the shade of the canopy of leaves as in the summer.
Stomata are small pores on leaves that play a central role in photosynthesis by allowing carbon dioxide to enter the leaf and oxygen to exit the leaf. So my next thought was how does the exchange of gases occur in the stem if it is photosynthesizing?
The Royal Horticultural Society had this to say on their website: “Leaves and soft, green stems have living cells in contact with the air, and they can absorb oxygen for respiration directly through their surface. However, the bark of woody stems is impervious to gases, so to get oxygen to the active tissue beneath, it is perforated by pores called lenticels.”
In the photo above, I think the woody little bumps are lenticels. When reading about lenticels, the articles were about them absorbing oxygen and releasing carbon dioxide and water vapor during respiration. I haven’t found any articles involving lenticels and photosynthesis yet. As a side note, I thought that it was interesting that apples, potatoes, and avocados have lenticels too.
I am still researching photosynthesis in the green bark of trees, but I thought I would share some of what I have learned so far to get you interested in reading about it too.
Resources
Bigleaf Maple (Acer Macrophyllum) | Oregon Wood Innovation Center. https://owic.oregonstate.edu/bigleaf-maple-acer-macrophyllum#:~:text=Size%2C%20Longevity%2C%20and%20Form&text=Bigleaf%20maple%20is%20moderately%20long,after%2050%20to%2070%20years. Accessed 20 Feb. 2024.
How Plants Breathe / RHS Gardening. https://www.rhs.org.uk/advice/understanding-plants/how-plants-breathe. Accessed 20 Feb. 2024.
Check this out. Out in the south meadow, some bigleaf maples are growing out in the full sun and the young bark on the stems is red. Can these photosynthesize too? Why are they red?
Oak Leaves
Check out these oak leaves that I put in a slideshow. I collected them off the ground under a cluster of oak trees. I was so surprised and fascinated by the amount of variation in shape. I wondered how the field guides on my shelf described the leaf’s shape. Here’s how four different books define it:
Cascade-Olympic Natural History:
“…deeply pinnately blunt-lobed.”
Plants of the Pacific Northwest Coast:
“…deeply round-lobed oak leaves.”
Trees to Know in Oregon:
“Pinnately lobed with 7-9 rounded lobes; lobes often irregular.”
Trees and Shrubs of the Pacific Northwest: “…oval to egg-shaped… edges deeply lobed, lobes and leaf tip rounded.”
I searched for the term pinnately lobed and the University of Texas at Austin defined it as: “PINNATELY LOBED: lobes are arranged on either side of a central axis, like a feather.”
Having never seen an Oregon White Oak leaf, would you have visualized these leaf shapes in the photos based on the definitions from these books? Also, having seen an Oregon White Oak tree, what leaf shape would you have drawn from memory?
References
Botany Basics: Understanding Leaves. https://biodiversity.utexas.edu/news/entry/leaves. Accessed 10 Feb. 2024.
Jensen, Edward C., et al. Trees to Know in Oregon. Rev. April 2005., Oregon State University, 2005.
Mathews, Daniel. Cascade-Olympic Natural History. Raven Editions in conjunction with the Audubon Society of Portland, 1988.
Pojar, Jim, and Andrew MacKinnon. Plants of the Pacific Northwest Coast: Washington, Oregon, British Columbia & Alaska. Revised ed, Lone Pine, 2004.
Turner, Mark, and Ellen E. Kuhlmann. Trees & Shrubs of the Pacific Northwest. First edition, Timber Press, 2014.
A Tree Inside a Tree
Scattered across the ground, are heaps of branch tips of big leaf maples that broke off during the ice storm. I picked one up and admired its shape, color, and texture. I sat down, did a brief sketch of it, and continued to admire its beauty. Afterward, I cut a cross-section to see what it looked like inside. To my surprise, I found a small tree enshrined in a kind of mandorla. (In Italian it means almond. In religious art, it’s the almond-shaped aureole of light surrounding the entire figure of a holy person like the Virgin Mary.)
Nature is an inexhaustible source of wonder. I look forward to seeing you out there.
Canopy Opens
Last fall or winter (maybe it was two years ago), an old Bigleaf Maple tree split in half. The tree forked near the base and had become rotten inside. Half of it is still standing and being propped up by other trees. The other half was leaning towards the trail, so for safety, the arboretum cut it down. This opened up the canopy allowing the sun to reach into the forest that was mostly in the shade. As a result, numerous sprouts have started to emerge from the trunks of these Bigleaf Maples that were growing next to the Grandmother maple. It will be interesting to see how these new shoots develop and the landscape fills back in over the next 20 or 30 years.
Favorite Tree
Every time I go out to the arboretum, I remind myself to slow down and take my time. I often begin by sitting on a bench, tuning into my senses, and letting go of all the busyness in my life. I hear chickadees calling, crickets singing, and leaves rustling. I feel the warmth of the sun and the wind brushing against me. I smell the dampness of recent rains and leaves starting to decay. I taste some ripe blackberries. I see insects buzzing in the air, and squirrels climbing through the trees. There are so many discoveries to be made in nature and it is more likely to happen if I start this way.
After sitting for a little while, I took a walk out to my favorite tree. It has so many beautiful forms, patterns, colors, and textures to behold and experience. It stands upright and its canopy is open and spacious.
The needles are long, soft, and green. They radiate outwards forming wispy brooms that sweep back and forth in the wind. The old needles turn orange and are scattered in a loose mat underneath the tree.
There are old cones still attached to the tree. They are gray and small bits of lichen are scattered across their surfaces. The scales are still nestled together at the base forming a beautiful pattern. Some old cones have partially detached leaving behind barnacled florets. The new cones have opened in the warm, summer sun. Their copper-colored bodies develop into a bouquet of arching scales. Red-breasted Nuthatches visit the cones looking for seeds to eat or cache for later.
Its catkins are tubular and dry a papery, reddish-brown.
The tree produces a sticky sap that always manages to find its way onto my body or clothes somewhere. It has a cool, sharp scent that feels refreshing.
The bark of the trunk is layered with flakes creating a furrowed, craggy landscape. It has a warm, sweet smell. The bark on the young limbs is reminiscent of a snake’s skin.
It has a gentle song and a peaceful dance as it sways in the wind.
There is so much to learn, notice, and experience with this tree. It can live to over 500 years old. This is only the beginning of its life. I will only get to know it and be friends for such a brief time.
