May 7th, 2014 by UWBG Communication Staff
Wonder what goes on in the labs of Merrill Hall or in the study plots sprinkled throughout Union Bay Natural Area? Find out at the annual UW Botanic Gardens graduate student research review May 9 to June 13 in the Library.
Want to meet the researchers? Then join us for the public reception Friday, May 9 from 5 to 7pm. Light refreshments will be served. The public is invited to this free event.
Participating students and research topics
May 6th, 2014 by UWBG Communication Staff
By John A. Wott, Director Emeritus
This photograph, taken on April 4, 1950, is located somewhere to the left of the location of the Lookout Shelter. It points southwest. Originally, the hillside held a large collection of Ceanothus, but they were killed during severe winters and never replaced. If one looks closely you can see “tracks” on Azalea Way, the outline of Arboretum Creek, and East Lake Washington Boulevard. It appears there is one house on the lower level of Interlaken Boulevard East, and of course, many homes on the slopes of Capitol Hill are easily seen.
Looking southwest to Lake Washington Blvd and Capitol Hill from Ceanothus area by the Lookout Shelter
The kiosk at the intersection of East Lake Washington Boulevard and Interlaken Boulevard East is visible. Note how open the area is with small collection plantings and few towering native trees. This was taken before the construction of the Japanese Garden.
May 6th, 2014 by Soest Gardener, Riz Reyes
Joseph Rock’s Peony has been prized by gardeners and avid collectors for decades. Botanist and plant explorer Joseph Rock earned the honor of having this exquisite flower named after him.
Peonies are divided into two basic types; the bush or herbaceous peony and the so-called tree peony. With similar flowers, the main difference between the two are their bloom times and their growth habit. Herbaceous peonies die back down to the ground each winter and bloom later in the season (May-June) whereas the tree peony, which isn’t really a tree, is more like a shrub with stems and branches that do not die back to the ground and flower mostly in May. Paeonia rockii is a tree peony.
Tree peonies are long-lived shrubs with exquisite flowers, but they take careful placement and a lot of patience until they’re well established.
They are best planted in the autumn so they are able to start forming new roots over the winter and it’s critical that they are planted in a location with full/part sun, well drained soil, good air circulation, and protected from strong winds that could damage the brittle branches. They can take several years to get established to consistently bloom each year and they also resent being transplanted.
Common Name: Joseph Rock’s Tree Peony
Location: Pacific Connections – China Entry
Origin: Gansu, China
Height and Spread: 6-8′ tall and about 5-7′ wide
Bloom/Fruit Time: Early-Mid May
A few selections of P. rockii can also be found growing at the Seattle Chinese Garden.
May 4th, 2014 by Catherine Nelson, Adult Tours Program Assistant
Paulownia tomentosa, Common name Empress Tree
Right now this tree’s large purple panicled flowers, which look similar to foxglove flowers, are blooming and the scent is wonderful. There are several in the UWBG collection, most located at the North end of the park where the wetlands trail begins.
It is a very fast growing tree that can reach 80 ft. in height, and is prized for its large heart-shaped fuzzy leaves. The large size of young growth can be enhanced if the tree is pollarded yearly; the pruning encourages growth of leaves up to 16” across.
It is classified as an invasive plant in the Southern United States, where it sends out invasive roots and can take over the area it is planted in. The Paulownia here in the Pacific Northwest do not behave invasively, probably due to our cooler climate.
The name Paulownia is in honor of the Grand Duchess Anna Pavlovna of Russia, with tomentosa being derived from the Latin meaning ‘covered in hairs’.
Paulownia is cultivated as an ornamental tree in parks and gardens. It has earned the Royal Horticultural Society’s Award of Garden Merit.
In its native China, an old custom is to plant an Empress Tree when a baby girl is born. The fast-growing tree matures when she does. When she is eligible for marriage the tree is cut down and carved into wooden articles for her dowry. Carving the wood of Paulownia is an art form in Japan and China. In legend, it is said that the phoenix will only land on the Empress Tree and only when a good ruler is in power. Several Asian string instruments are made from P. tomentosa, including the Japanese koto and Korean gayageum zithers.
May 3rd, 2014 by UWBG Horticulturist
Selected cuttings from the Washington Park Arboretum (April 28 – May 11, 2014)
1) Rhododendron spp. Azalea
- Azaleas are in the genus Rhododendron, with evergreen azaleas in the subgenus Tsutsusi and deciduous azaleas in the subgenus Pentanthera.
- The Olmstead Brothers originally planned for 11,000 azaleas to be planted along Azalea Way. More than 3,100 have been planted and over 2,000 remain.
- Azalea Way contains 21 species of azalea and more than 200 hybrids.
2) Tsuga heterophylla Western Hemlock
- Our native western hemlocks are currently laden with new female cones which are deep purple when immature.
- Currently, a scientific experiment is being conducted as a collaboration between the Washington Park Arboretum and the University of Massachusetts, using the collection of T. heterophylla and T. canadensis.
- We are studying the predator/prey relationships among the hemlock Wooly Adelgid, eastern and western hemlocks, and the predator species that prey on the Adelgid.
3) Syringa oblata var. dilatata, S. patula Lilac
Close-up photo of newly-forming female cone on Larix decidua
- Our Lilac Collection contains more than 14 species along with several more hybrids.
- Our primary lilac display is on Azalea Way, just south of the Woodland Garden.
4) Larix decidua, L. kaempferi Larch
- Now is a great time to admire many conifers for their display of young and old cones on the same branch.
5) Rhododendron ‘El Camino’ Halfdan Lem hybrid
- Our Puget Sound Rhododendron hybrid bed is located on Azalea Way south of our Lilac Collection.
- This bed contains plants from local hybridizers dating back to the early 1940s.
April 24th, 2014 by UWBG Horticulturist
Earth Day 2014
On Saturday, April 12th, over 220 people joined together at Washington Park Arboretum to celebrate Earth Day with SCA! The day began with Seattle mayor Ed Murray, SCA founder Liz Putnam, current SCA student Diana Furukawa, and others celebrating the day and imploring volunteers to consider the effects of climate change and to take action in their communities. SCA youth lead eight volunteer groups around the park. Together volunteers accomplished the following:
- 14,044 sq ft invasive plants removed
- 40 cubic yds mulch spread
- 205ft trail maintained (graveled)
- 94 plants potted
Check out amazing photos from the day here!
Check out the project map:
Text and photos contributed by SCA
April 24th, 2014 by UWBG Horticulturist
A mature western hemlock, Tsuga heterophylla, is scheduled for removal on Wed, April 30. It is located in Rhododendron Glen, north of the Glen pond.
- Fungal conks seen growing on the trunk is an indicator that a rot inducing pathogen is present.
- Its hazard potential is great due to extensive internal decay.
- A wild-life snag will be left in place.
Each tree requires evaluation to determine the best course of action for the site.
Conks growing on hemlock trunk
April 21st, 2014 by Jessica Farmer, Continuing Education Coordinator
Trees of Life: 14 artists honor the beauty and mystery of Emerald City’s trees as a Seattle Tree Ambassador graduate hosts local art show reception
Friday, April 25
5 – 7 pm
University Friends Meeting Social Hall Art Gallery
4001 9th Ave NE, Seattle
Free; light finger food provided
For more information, contact Clarena at email@example.com or 206-632-9839
Exhibit runs through the end of June; hours are Mon – Fri, 9:30 am – 1 pm; Sat and Sun 10 am – 1 pm or by appointment.
This exhibit, curated by a Tree Ambassador, showcases the artwork of trees by Pacific NW artists as a way to inspire and help Seattle’s residents reconnect with nature, specifically the beauty, wisdom, and mystery of trees. The Tree of Life, an ancient and powerful symbol, is deeply embedded in the human psyche. It represents and evokes life, even before science proved its role in providing oxygen and transmuting carbon dioxide.
The 15 Pacific NW artists represent the UW School of Art, the University of Puget Sound School of Art, Sierra Club members, and local community artists from young children to the professional award-winning artist are represented. They have used different media and approaches to expressing the beauty of trees.
Read the full news release and the Trees of Life Curator Statement.
April 20th, 2014 by UWBG Horticulturist
Selected cuttings from the Washington Park Arboretum (April 15 – 28, 2014)
1) Melicytus angustifolius
- This southern hemisphere Violaceae relative thrives in rocky places in mountains or on coasts, or in evergreen forests.
- Is ‘dioecious’ or ‘of two houses’ in Greek translation; male and female flowers are present on separate plants.
2) Erica arborea var. alpina
- Found along the southern end of Arboretum Drive, this is one of the older collections in the Washington Park Arboretum, dating back to 1947.
- This form, var. alpina, is a smaller shrub, very hardy, and with brighter green foliage, making an imposing highlight among smaller heaths and heathers.
3) Poncirus trifoliata (syn. Citrus trifoliata)
- Bitter, non-edible yellow fruits that resemble a small orange
- Two large specimens in the Arboretum found in grid 8-1W and 12-B, north of the large parking lot off of Lake Washington Bouvelard.
4) Viburnum carlesii var. bitchiuense
- This spicy smelling Viburnum is the intoxicating fragrance you’ll be hit with the moment you walk out the front door of the Graham Visitor’s Center.
- Listed on the IUCN Red List of Threatened Plants in 1997, our cultivation of this plant helps to preserve a propagation source for future plants.
5) Phyllocladus alpinus
- This New Zealand conifer can photosynthesize through highly modified, leaf-like shoots called phylloclades as well as through leaves.
- The newly-formed seed cones are berry-like, with a fleshy white aril.
- Male and female flowers are separate, but borne on the same plant.
April 19th, 2014 by Catherine Nelson, Adult Tours Program Assistant
Rhododendron macabeanum is one of the finest big leaved Rhododendron species and has received the Royal Horticultural Society’s Award Of Garden Merit. It has large yellow/white flowers often blotched purple inside with an interesting bright pink stigma. The leaves are a dark glossy green and about 1′ in length with a light colored indumentum on the underside. It also bears a nice silvery young leaf and bright red bud scales.
Native to India at high elevations, this plant was introduced to the West in 1927. We have a wonderful specimen in the arboretum. It is blooming right now and is located between the SE corner of Loderi Vally and the Magnolia Collection. Our April Free Weekend Walks on Sundays at 1:00 pm will continue to feature this and other amazing Rhododendrons in the UWBG collection.