February Color Appears at the Washington Park Arboretum

February 4th, 2015 by UWBG Horticulturist
Selected cuttings from the Washington Park Arboretum (February 2 - 15, 2015)

Selected cuttings from the Washington Park Arboretum (February 2 – 15, 2015)

Donald Culross Peattie in the Washington Park Arboretum

Staff horticulturist, Ryan Garrison recently listened to an audio version of Donald Culross Peattie’s book, “A Natural History of North American Trees.” He very much enjoyed its mix of science and literary art, and would like to share a few gems about trees in the collection with you.

1)  Carya ovata – Shellbark or Scalybark Hickory
“To everyone with a feeling for things American, and for American history, the Shagbark seems like a symbol of the pioneer age, with its hard sinewy limbs and rude, shaggy coat, like the pioneer himself in fringed deerskin hunting shirt. And the roaring heat of its fires, the tang of its nuts – that wild manna that every autumn it once cast lavishly before the feet – stand for the days of forest abundance.” 1

2)  Pseudotsuga menziesii – Douglastree; Douglas, yellow, or Red Spruce; Oregon Pine
“In the literature of forestry it has wavered between Douglas Fir and Douglas Spruce, though it is no Spruce and no true Fir, as botanist see matters. Some years ago the Forest Service officially settled on “Douglas Fir” and if this impaction seems to you to clear up matters, you may use it with the blessings of the Government Printing Office. The least misleading of proposed names is Douglastree, since it leans on no analogies and still does honor to that noble pioneer among explorer-botanists of the Northwest, David Douglas.” 1

3)  Sequoia sempervirens – California Redwood, Coastal Sequoia, Sempervirens, Palo Colorado
“Your footfalls make no sound on the needles and moss that have lain there for centuries. Your body casts no shadow in that green, lake like diffused light. The goose honking of a car, the calling of a child, fade into the immensity of silence. Time, the common tick-tock of it, ceases here, and you become aware of time in another measure – out of an awesome past. For this forest has stood here since the Ice Age, and here, together with this transfixed past, is the future too, for these immense lives will outlast yours by a thousand years or so.” 1

4)  Sequoiadendron giganteum – California Bigtree; Sierra Redwood; Mammoth-tree
“The summers are exceedingly dry; if rain does fall it is apt to come with violent thunderstorms and lightning bolts that have been seen to rive a gigantic Sequoia from the crown to its roots. Those who know the species best maintain that it never dies of disease or senility. If it survives the predators of its infancy and the hazard of fire in youth, then only a bolt from heaven can end its centuries of life. Perhaps, if this majestic tree had a will, it would prefer to go this way, by an act of God.” 1

1 Peattie, Donald Culross, and Paul Landacre. A Natural History of North American Trees. Boston: Houghton Mifflin, 2007. Print.

Glimpse into the Past – Remembering the First Northwest Flower & Garden Show

February 4th, 2015 by UWBG Communication Staff

By John A. Wott, Director Emeritus

A former staff member, Rebecca Johnson, shared with me a copy of the “First Annual Northwest Flower and Garden Show” program, held on Presidents’ Day Weekend, February 17-20, 1989.   On February 10, 2015, the 26th Show will open. I am proud to say that I have attended each one, including the Preview Party, a benefit for the Washington Park Arboretum. This 48-page colored glossy printed program was a synopsis of horticulture in the Northwest at that time.  The cover photograph, taken by the late Jerry Sedenko, features the Streissguth Garden, now a public garden on the slope of north Capitol Hill.

cover photo

This indeed was an exciting event, showcasing such a sizable indoor garden  display never before seen here.  A dream come true of the founder and owner, Duane Kelly, it was patterned after the fabulous shows of Boston, New York, and  Philadelphia.  Jane Pepper (Philadelphia) and Richard Daley (Mass. Hort. Society)  were advisers.  Duane’s vision and enthusiasm for the Seattle show is expressed in the “Welcome to the Show” program introduction.  The appreciation list is a glimpse of Northwest horticulture leadership including Dr. Harold Tukey, Nancy Davidson Short, Steve Lorton, Jerry Wilmot, Egon Molbak, and Ann Lovejoy as well as Kathleen Brenzel of Sunset Magazine.


The 25 gardens were built and sponsored by Molbak’s, Star Nursery, Iseli Nursery, Briggs Nursery, Swanson’s, Rodda and Sons, Weyerhaeuser Nursery Products,  Weyerhaeuser Specialty Plants, Price Ragen, Magnolia Lawn and Garden, Washington Park Arboretum, Barford’s Hardy Ferns, Furney’s, Seattle Water Department, Seattle Parks Volunteer Park Conservatory, Jackson and Perkins, Skagit Gardens/Wight’s, Highridge Corporation, Puget Sound Bonsai, Ikebana International, Big Rock Garden, Bamboo Brokerage, Columbia Greenhouse, FTD Florists, and Boeing Aerospace Company. There was also a children’s garden.  The entire garden layout plus all the retail booths were on the fourth floor.


The center section of the program contained colored pictures and short descriptions of 26 Northwest public gardens in an article written by Nancy Clark Hewitt in which she states that “the Northwest is blessed with an excess of natural beauty inspired by nature’s bounty.  A rich gardening tradition has developed here, and is to be showcased in the show. “


From the very moment of conception Duane wanted the Northwest Flower and Garden Show to be educational, and I was privileged to plan and lead these free lectures and seminars for those first years, then held on the sixth floor.  As stated by Duane, “these programs “represent the greatest amount of horticultural, floral, and landscape knowledge ever assembled under one roof in the Northwest.”  We were overwhelmed with attendees and early on struggled to contain waiting lines.  In addition the show offered free booth space to horticultural societies where the public could find answers and talk to local experts.

Over these 26 yrs, the NWFGS has changed with the times, but it is still one of the best indoor garden shows of the USA, if not the world.  Why not follow in the footsteps of thousands and attend the forthcoming Northwest Flower and Garden Show, “Romance Blossoms?”

Northwest Horticultural Society 2015 Plant Sale

February 4th, 2015 by Jenelle Clark

Camellia japonica ‘Jupiter (Paul)’. One of the many winter treasures growing at the Arboretum.

Alert, serious plant lovers: Get your hands on rare and ephemeral early spring plants at the 2015 Northwest Horticultural Society’s Spring Plant Sale, March 7th at 9:00 am – 3:00 pm. Proceeds benefit the Elisabeth C. Miller Library.

Please join us for a special lecture, Late Winter Treasures of the U.W. Botanic Gardens, by Raymond J. Larson, the Curator of Collections at the University of Washington Botanic Gardens. The lecture begins at 10:00 am.


February 2015 Plant Profile: Sarcococca

February 3rd, 2015 by Soest Gardener, Riz Reyes

Sarcococca ruscifoliaWinter garden in the Pacific Northwest seems incomplete without this landscape standard. It has lush, glossy, evergreen foliage year round, takes dry shade conditions, and flowers in the wintertime with a powerful scent that perfumes the landscape. Sweet Box comes in two basic forms for the home gardener: the tall form and short form. The tall form (S. ruscifolia and S. confusa) get to about 2-3 feet in height and wide. The short form (varieties of S. hookeriana) makes somewhat of a groundcover with underground stolons that form a clump no taller than 12 inches and can spread about 3 feet.

In the garden, the ideal location for Sweet Box is under part shade with regular irrigation the first few seasons to get it established. It works well as a foundation planting up against the house and in mixed beds in a shaded woodland garden. Despite its common name and close relationship, Sweet Box can’t be treated like regular boxwood (Buxus sempervirens) and be sheared on a regular basis. To keep the size and shape in check, prune only the tall forms and prune shortly after they’ve finished blooming (March-April). This forces new growth and stems that will then flower the following winter. Pruning during the summer and fall will remove the new growth; therefore, the flower buds are sacrificed.

Genus: Sarcococca
Common Name: Sweet Box
Location: Fragrance Garden
Origin: Eastern and Southeastern Asia, Himalayas
Height and Spread: Tall (2-3′ height x 3′ spread) – Short (1′ height x 3′ spread)
Bloom/Fruit Time: Late December-late February



Get a jump start on spring at the 2015 Northwest Flower & Garden Show

January 30th, 2015 by Jenelle Clark

Flower show logoSpringtime is on the cusp of arrival here in Seattle, which means it’s time once again to be immersed in the rich sensory wonder that is the Northwest Flower & Garden Show (NWFGS). Heralding the beginning of the new growing season, the NWFGS celebrates gardening by showcasing spectacular planting designs and provides a myriad of opportunities to learn more, stock-up on plants, and let your imagination run wild. The show will be held this February 11-15th at the Washington State Convention Center.

Make sure to stop by the UW Botanical Gardens’ educational booth, #2513, to explore the many opportunities we’ll be offering this year to develop new gardening skills and immerse yourself in the beauty of the Botanic Gardens. The UWBG booth theme is “Discover & Learn,” and will highlight the Arboretum’s interactive map, our year-round educational opportunities, and the iconic locations throughout the botanic gardens.

“Romance Blossoms” at the 2015 Northwest Flower & Garden Show

The theme for this year’s show couldn’t be more fitting for Valentine’s Day weekend. “Romance Blossoms” will be the inspiration behind the 21 featured show gardens, designed by the region’s top landscape designers. This year, following suite with the show’s theme, the gardens will display even more rich floral abundance, 50% more to be precise. This is due to the show’s commitment to an expanded “forcing” program in collaboration with two local growers.

A Successful Failure

January 30th, 2015 by Kathleen DeMaria, Arboretum Gardener

The Washington Park Arboretum rang in the new year with a series of windstorms that broke limbs, downed trees and dulled chain saws. What the storms didn’t do, however, was cause extensive damage to collections, structures, or visitors. “Lucky” might be your first thought, but luck had little to do with it. Proper tree care and a knowledgeable and observant tree care crew allow us to consider our recent tree ‘failures’ successful.

UWBG Arborist, Chris Watson ascends a Hemlock that he is removing. Because this is a removal Watson is using spikes on his boots to assist him with his long climb. Spikes are never worn on trees we prune as they can damage bark.

UWBG Arborist, Chris Watson ascends a Hemlock that he is removing. Because this is a removal Watson is using spikes on his boots to assist him with his long climb. Spikes are never used on trees we prune as they can damage bark.

chris ascending shadow

An early morning climb

Our biggest break in January was one of the Hemlocks that line Arboretum Drive. Years ago it developed a ‘double leader’, or ‘codominant stem’ (2 or more main stems with similar diameter that emerge from the same location on the main trunk). Codominant stems can be challenging as the tree grows because the stems push against each other as they grow together, causing deformity that often results in compressed wood and ‘included bark’. These factors can often lead to a weak spot in the tree that may be susceptible to failure.

UWBG Arborist Chris Watson had been monitoring this Hemlock for years and decided to place a cable in the tree a few years ago to prevent any serious breakouts. His decision and placement were both great moves, as this tree did succumb to the wind, but the broken leader remained cabled to the stronger leader and no damage occurred.

Best view in the Arboretum

Best view in the Arboretum. Watson carefully contemplates his next cut.

You have to work hard for the view.

You have to work hard for the view.

















Anybody who has ever taken a class in the Arboretum with Dr. Bob Edmonds has likely heard him discuss the fungal pathogen Armillaria mellea, commonly called Armillaria root rot, shoestring root rot, or honey mushroom. Unfortunately we have this pathogen in our soils and occasionally when a tree we suspect has the disease falls, we get a chance to investigate. We (and Dr. Edmonds) suspected this tree had Armillaria.

Tell-tale signs of Armillaria mellea include: White, fan-shaped mycelium growing on the inside of the bark and over the sapwood, soft, spongy and stringy wood that has a lighter yellow coloring, and finally and often most noticeable, black shoestring-like ‘rhizomorphs’ in the dead and dying wood at the base of the tree. Upon investigation of this tree, we did find multiple signs of Armillaria including rhizomorphs, white fans of mycelium, soft spongy yellowed wood, and a column of rot in the center of the trunk that the tree had compartmentalized pretty well over the years.

UWBG’s horticulture staff’s diligent monitoring and tree care regimes turned this failure into a great research and teaching opportunity in our living classroom called the Washington Park Arboretum. Come discover and learn with us.


Rhizomorphs from the fungus can be seen here and under a microscope.

Black Rhizomorphs  can be seen here and under a microscope.

Hollow center of this Hemlock indicates decay that the tree has been compartmentalizing for years.

Hollow center of this Hemlock indicates decay that the tree has been compartmentalizing for years.

Soft, spongy and discolored wood where the tree broke indicate the presence of Armillaria.

Soft, spongy and discolored wood where the tree failed indicate the presence of Armillaria.

Winter with Fiddleheads Nature Class

January 27th, 2015 by Sasha McGuire, Education Program Assistant

Investigating a spider sighting




The winter session of Fiddleheads Family Nature Class is in full swing this month, despite the weather. Preschoolers aged 2-5 are learning how winter is special, what a skeleton is, what a fossil is and how they form, and even delving into a little chemistry! Every week is a different theme with fun new activities to get you and your little one interested in science, nature, and the world around us.




Taking a closer look at a slug

Taking a closer look at a slug



Classes are Tuesday-Thursday mornings from 10am-12pm with a special Wednesday afternoon session from 1:30-3:30pm for preschoolers ages 4-5.

More information on price, time, discounts, location, and topics.

Call 206-685-8033 or email uwbgeduc@uw.edu for more information.



What lives in a pond?

What lives in a pond?



Upcoming topics:
I Can Be a Scientist! – February 3-5

Trees Grow Up, Too – February 10-12

How Animals Move – February 24-26

Spying With Our Eyes – March 3-5

Sounds of the Forest – March 10-12

Fun In the Mud – March 17-19

Snails, Slugs, and Slimy Things – March 24-26















January Color Appears at the Washington Park Arboretum (Part II)

January 25th, 2015 by UWBG Horticulturist

Witt Winter Garden

Selected cuttings from the Washington Park Arboretum (January 19-31, 2015)

Selected cuttings from the Washington Park Arboretum (January 19-31, 2015)

1)  Cornus sanguinea ‘Midwinter Fire’         Bloodtwig Dogwood

  • Young stems of this cultivar are orange-yellow with the sunny side turning carmine red.
  • Stem color of species is gray to purple, while the color of C.s. ‘Midwinter Fire’ is yellow-green in summer changing to winter colors rapidly at leaf drop in fall.

2)  Hamamelis x intermedia ‘Pallida’             Witch Hazel

  • This hybrid of H. japonica and H. mollis was selected for its pale sulfur-yellow flowers which tend to glow in the low light levels of morning and evening.
  • Cultivars of witch hazel can have flower colors from pale yellow to deep red, some being quite fragrant while others are much less so.

3)  Lonicera standishii                   Honeysuckle

  • This semi-evergreen shrub bears fragrant flowers from early winter to early spring.
  • Lonicera standishii is native to China.

4)  Ruscus aculeatus                    Butcher’s Broom

  • Lacking true leaves, what you are seeing are called “cladophylls” which are simply flattened stems.
  • The flowers of this plant are dioecious, only 2 mm across and are located in the center of the cladophylls.
  • Butcher’s Broom is native to Europe, Turkey, North Africa and the Azores.

5)  Viburnum tinus ‘Pink Prelude’                Laurustinus

  • This species has been cultivated in England since the 16th century.
  • V.t. ‘Pink Prelude’ has white flowers that age to pink.
  • The flowers of laurustinus are followed by small, but showy metallic-blue fruit.

Zip-lining through the mist in Costa Rica

January 23rd, 2015 by Sarah Reichard, UW Botanic Gardens Director

One last bird, before I return to plants! The blue-crowned mot mot, photo by Michael Hobbs.

After reading through the blog posts about my recent trips to Cuba and the Costa Rica trip just concluded, I have realized I am becoming one of those people. You know. Bird people. The ones who get excited about the birds they are seeing, missing out on the fabulous plants altogether. Okay, well maybe not that extreme – I still get pretty excited about the plants, but I am starting to see the attraction of birds. Especially large, colorful birds like the mot mots, which sit still long enough for you to find them in the binoculars. I don’t expect to become a birdaholic like many of my fellow travelers, especially if it means getting up before dawn, but I do see the attraction.

As for plants, in addition to the Gunnera insignis that I mentioned earlier, my second favorite new species in Costa Rica is probably Pitcairnia brittoniana. It is a epiphytic bromeliad that grows on the sides of trees or embankments with an impossibly red inflorescence that also grows sideways, rather than the upright form of most bromeliads. Its vibrancy shouts “look at me!” through the gloom of the cloudy forests of Monteverde.


The dramatic Pitcairnea flower.

The dramatic Pitcairnea flower.

Another favorite at Monteverde was a liana in the pea family. For many years it has been known as Mucuna urens, but recent studies have thrown that species into question. The seeds are quite large and the pods have an interesting reticulated pattern. They provide nectar to the bats which pollinate the flowers, food for the larvae of the beautiful large blue morpho butterflies in the forests, and the large seeds are food for agoutis, a common large rodent. And they look cool.

Our guide, Jimmy, show us the large pods and seeds of Mucuna.

Our guide, Jimmy, show us the large pods and seeds of Mucuna.

It was also fun to see so many of the houseplants we grow in their native habitat. The split-leaf philodendron (Monstera deliciosa) was everywhere. Plants in the African violet family, like Columneas (goldfish plant), were both understory and epiphytic plants. Dieffenchias (dumb cane) found in every bank lobby in North America, are tropical understory species that are a favorite food of peccaries, a kind of wild pig. And the orchids were amazing – we visited an orchid garden that had only orchids found in Monteverde – and there were hundreds of them.


The view from our water taxi as we sped across Lago Arenal towards Monteverde.

But back to the trip: we left Volcan Arenal by boat, specifically an open-sided sort of water taxi that unofficially operates on Lago Arenal, a lake greatly enlarged by a dam to generate electricity. “Unofficially,” because the government agency that manages the dams does not want it used for such things, though it is clearly very common. It was misty as we crossed the water, landing at a location that is apparently a major ferry stopping point for travelers (lots of backpackers!) making their way between the cloud forests of Monteverde and Arenal. Despite the apparently hundreds of people using the site for embarking/disembarking every day, we scrambled up a muddy slope. Our guide, Jimmy, said that they do not put in pavement and steps because it is an “unofficial” landing spot.


The ferry landing near Monteverde, with mobs of backpackers coming and going.

We bumped along in our hired van for about an hour, before landing at our very nice hotel, with fantastic views out to the Pacific Ocean. The next morning we had our excursion to the cloud forest, where we reveled in spotting the Resplendent Quetzal. In the afternoon several of us experience zip-lining for the first time. It was supposed to be a canopy line, but it was VERY cloudy – and windy – as we allowed ourselves to be clipped to cables to zip off into the unknown – truly unknown because you could not see more than a few yards into the clouds. Forget seeing much of the canopy. It is bizarre to see your friends zipping off and disappearing into a cloud and even more bizarre to do it yourself. More than once, we questioned our wisdom at embarking on this journey, especially as the winds whipped at us. By the end, they were sending us down two at a time (legs of the rear person wrapped around the body of the front person) to increase the weight and prevent us from getting stuck part-way across because of our cable attachments “braking” on the cable as we were tossed around by the wind. It was a grand adventure but we were all (except maybe Jana) relieved to come to the last of the eight lines.

After the intense experiences we had together, it was sad to have our final dinner, knowing that by early morning some of us would be heading home, while others went on to further adventures in Costa Rica. It was a great group to travel with! We shared some amazing adventures and I can’t wait to meet up with them again soon.


We visited an orchid garden in Monteverde, where our young enthusiastic guide reminded me of our own gardener, Riz Reyes.


Our happy group. Our guide, Jimmy, is kneeling in the front and our driver, Enrique, is standing in a blue shirt.


MLK Day of Service: UBNA Work Party in Review

January 20th, 2015 by Elyse Denkers


On Jan, 19, also known as the MLK Day of Service, a group of 7 volunteers helped remove ivy from cottonwood trees near the Union Bay Natural Area waterfront.
Just along the UBNA loop trail at the waterfront viewing area, many of the cottonwood trees have been suffocated by invasive English ivy. These trees may become a safety hazard for trail-users as ivy foliage weighs down branches.

Our goal was to create “life-rings” around the impacted trees by 1) cutting ivy at a 5 ft height around the tree, 2) peeling the ivy back off the tree, and 3) digging the ivy roots out of the ground around the tree base.
The ivy still hanging on the tree will eventually die without a soil sources.


P1010224 We finished our goal of creating life-rings and removing some ground ivy, but we still have more ground ivy to remove in this area.
Another work party we be scheduled in the next few weeks to finish this area and move on to rescuing the cottonwood trees across the trail.

If you are interested in helping finish this project, please see the UW Botanic Gardens volunteer calendar. New volunteer events will be posted there. You may also contact Elyse Denkers, UBNA research assistant, directly at edenkers@uw.edu