The Red Maples are flowering

March 24th, 2013 by Catherine Nelson, Adult Tours Program Assistant

acer rubrum flowerThe Red or Swamp Maple, Acer rubrum, is always noticed for its intense flame color in the fall, but I love these trees best right now – when they are covered in flowers prior to foliation.

From a distance the light gray bark of the tree sets off the pink & maroon flowers creating a stunning effect – it’s as if the tree is full of red fuzz.  In order to see these gorgeous tiny flowers, you need to find a tree with low hanging branches and get up close; they are only about an 1-1 1/2″ long.

The Acer rubrum is native to North America, East of the Mississippi from the Southern US to Canada.  The tree is monoecious and carries both male and female flowers, but bears them on separate branches.   The flowers with a darker red color are identified as the females. It is a very popular street tree in Seattle, so keep your eyes open while traveling around the city right now, you can’t miss them.



Witch Hazels are in bloom

February 4th, 2013 by Catherine Nelson, Adult Tours Program Assistant

Hamamelis There are several species of Witch Hazel, genus Hamamelis, featured in the Witt Winter Garden, which is in all its glory this month. The colors range from yellow to orange to red and their scent is incredibly heady.
The plant’s common name comes from the Old English word “Wych” which means “pliable”. The pliable branches of this plant were used for water dowsing, which was a way to find underground water, hence this activity also is known as ‘water witching”.
The Witch Hazel and many other winter blooming plants are featured on the Free Weekend Walks held each Sunday at 1:00 pm.


Public Tours for 2013 Starting

January 4th, 2013 by Catherine Nelson, Adult Tours Program Assistant
Japanese Umbrella Pine

Japanese Umbrella Pine

The Washington Park Arboretum’s free Weekend Walk Program resumes in the new year. These 90 minute guided tours are free and open to the public every Sunday at 1:00 pm. No cost, no registration – just meet up at the Graham Visitors Center.
January’s tour is  Ancient Trees; our guides will show and discuss tree species which have been around for millennia – such as the Japanese Umbrella Pine (see photo).

In February our walks will highlight the Witt Winter Garden in all its blossoming glory.

The March tour is Our Favorite Plants, during which your guide will share plants and garden areas that they enjoy the most.

For further information or questions you can email me at More Arboretum tour options.


Take an enjoyable holiday walk at the arboretum

December 6th, 2012 by Catherine Nelson, Adult Tours Program Assistant

People often think that because it is winter there isn’t much to see in the park right now.  But this is a great time of year to walk through the arboretum with family and friends.  With the leaves gone from most of the trees, other features stand out that may not normally catch the eye.  Beautiful colors and patterns in bark are exposed, as are bird’s nests.  Interesting seed pods, berries, fruits and delicate catkins stand out.

The tree pictured is a deciduous conifer, the Metasequoia glyptostroboides or Dawn Redwood, in the pinetum.  With its needles gone, you really notice the beautiful striated cinnamon bark and ornament-like dangling pollen cones remnants.

So if you are looking for a quiet, free holiday activity, I suggest the following walk.  You can start out at the Graham Visitors Center and the friendly staff at the information desk can assist with directions and maps.   Start by heading West over the Wilcox Bridge and into the pinetum.  Continue South along the trail through the pinetum and into the holly collection – very Christmassy.  From the hollies you can cross back East over Lake Washington Boulevard to Azalea Way – there are new crosswalks installed along the Boulevard for pedestrian safety.  Then stroll back North along Azalea Way to the Visitors Center.  This walk is only a couple of miles and would take about an hour.  Happy Holidays!


WPA guides always learning more

November 6th, 2012 by Catherine Nelson, Adult Tours Program Assistant

The WPA guides and education staff recently visited Seattle’s Dunn Garden on one of our enrichment tours. We visit local gardens regularly as part of our commitment to further education so that we, as guides, can provide WPA visitors a great tour experience.
The Dunn Garden, like the arboretum, was designed by James Dawson of the Olmstead Brothers landscape design firm, While the WPA was designed in the 1930’s as a natural park to house the plant collection, the Dunn Garden is a private formal garden surrounding residences and predates our park by almost 30 years.
The two gardens have other connections. Ed Dunn, son of garden founder Arthur Dunn, served as the Arboretum Foundation president in the late 1950’s and was instrumental in the installation of the Japanese Garden. Many of the plants Ed Dunn installed in his garden were species he acquired through the WPA, purchased as extras by him when the arboretum would receive new collection plants.
Other similarities occur – I noticed that the Dunn, like the WPA, also featured some Douglas Firs with Hydrangea anomala vines growing up their trunks. I asked our docent if this was a Dawson design feature and was told that this was the influence of Elisabeth Miller, who was very involved the both gardens and founded the CUH’s Miller Library.
One of the most amazing features of the Dunn is the presence of many mature East Coast specimen trees like Sugar Maples, European Beech, and the largest Magnolia I have ever seen personally. The garden covers several acres separated in a variety of styles and is beautiful even in late autumn. I plan to return in the spring when flowers will be in their glory because I can only imagine how breathtaking it must be. The Dunn Garden is closed for the winter, but open again for tours in April, 2013. I highly recommend a visit . For more information their web site is


Autumn is at its peak

October 26th, 2012 by Catherine Nelson, Adult Tours Program Assistant


The Japanese maple collection in the arboretum boasts more than 90 different cultivars, many of which have been new plantings in the last few years.  This makes our collection one of the largest in the United States.  The Woodland Garden garden itself contains over 70 of these cultivars and the next couple of weeks is the time to see them in all their blazing glory.  The tree pictured is Acer palmatum, cultivar Osakazuki which is at the NE pathway into the Woodland Garden.  This photo does not do the vibrant red leaves justice, but this cultivar is considered to have the most intense crimson color of any of the maples.  It is a hardy grower which does not get much above 8′ tall even in extreme old age and has been listed in catalogs since the mid-1800s.


The name Osakazuki is a reference to its leaves which cup at the base, the literal translation is “saki-cup-like leaf.”

Please join one of our free weekend walks over the next couple weeks and view the amazing fall colors.   All tours meet at 1:00 pm, Sundays at the Graham Visitors Center.


Looking for Autumn Color

October 13th, 2012 by Catherine Nelson, Adult Tours Program Assistant

I walked through the arboretum this week looking for early fall color in the park. This Fothergilla major always seems to be one of our first color transformations and its brilliant  reds and oranges drew me to it as usual.

The Fothergilla major is a deciduous shrub native to the Southeastern U.S. where its common name is Witch Alder. Though not an alder, it is in the Hamamelidaceae family and, like its relative Witch Hazel, is a wonderful deciduous shrub for any garden.

Although the Japanese Maples are not quite turning as of this date, there is still great fall color to be seen in other trees like the Chestnut,Maples, Sumacs and others.
Our Free Weekend Walk topic from mid-October through at least mid-November will be on fall color.  Come on a tour and let us show you the Park in its autumn glory. Join us on any Sunday at 1pm in front of the Graham Visitors Center.


Trees are showing off their fall bounty

September 9th, 2012 by Catherine Nelson, Adult Tours Program Assistant

These 3-parted pods contain the seeds of the Koelreuteria paniculata or Golden Rain Tree. This tree is native to East Asia, China & Korea and is used as an ornamental for its flowers, leaves and seed pods. Although it is considered an invasive in the SE United States. The Arboretum’s free Sunday walks for the month of September will feature the “Fruits & Nuts” of this tree and many others in the collection. Come on our free walk with a knowledgeable guide – every Sunday, 1:00 pm at the Graham Visitors Center


It’s Hydrangea Season

August 13th, 2012 by Catherine Nelson, Adult Tours Program Assistant

All of the Hydrangeas in the park are at their prime flowering beauty right now. Its a great month to go on one of our free Sunday tours with a guide and walk down Arboretum Drive to view the variety of Hydrangeas in the UW collection which includes everything from exotic Asian vines to the bluest mopheads I’ve seen in a while to the pictured Hydrangea aspera – my personal favorite. The aspera is native to Western China. It grows to about 10′ tall and features lovely mauve lace cap flowers and fuzzy leaves and stems. Older bark exfoliates for a shaggy look. This wonder shrub will take more sun than most hydrangeas.
If you are interested in learning more about these great shrubs, join us on a August Sunday at 1 pm, tours leave from the Graham Visitors Center.


The Montezuma Pine

July 8th, 2012 by Catherine Nelson, Adult Tours Program Assistant

Our free Weekend Walks topic for the month of July is conifers, therefore it seems appropriate to feature one of my favorite trees in the arboretum collection: the Montezuma Pine located in crabapple meadow. The Pinus montezumae var. lindleyi is a stately tree with defined, tiered branches which droop down and then rise back up in a “J” shape at the end where the clusters of needles 10-12” long drape elegantly. It reminds me of a waterfall. This tree was added to the collection in 1965 and is native to Mexico and Central America, where it is called the ‘Ocote’ tree.

One of the websites I visited while researching the Montezuma Pine featured a full picture of our very own arboretum tree!  (my camera could not do it justice).

Please join us on a free Weekend Walk this month to see this and other amazing conifer trees in our collection. Walks meet at Graham Visitors Center at 1 pm every Sunday.