Washington Park Arboretum tree removal notification

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

Conks growing on hemlock trunk

 

 

 

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Harbinger of Spring in Seattle – Flowering cherries on Azalea Way!

March 20th, 2014 by UWBG Horticulturist

Cherry photoMost visitors experiencing the beauty of our historic Azalea Way flowering cherries from now through May probably have no idea of how intensive maintaining their health and prolonging their longevity truly is for the UW Botanic Gardens horticulture staff.   Just ask our Integrated Pest manager, Ryan Garrison. Ryan with staff support spends many a day throughout the year monitoring and controlling the numerous diseases and insect pests our 175 plus cherries are prone to suffer from. Our rainy climate doesn’t help one bit either, especially when dealing with our most notable disease during blossom time;  a fungus known as Cherry Blossom Brown Rot. Yucko!  The good news is any new cherries we plant need to show a reasonable level of resistance. The not so good news is many of our older earlier bloomers, the ones extremely susceptible to the brown rot fungus,  need to be protected with fungicide applications during their bloom period.  As with all of our pest issues, we start with cultural and mechanical control efforts before resorting to chemical controls. The following Integrated Pest management (IPM) program discusses our best management practices for the control of blossom brown rot.  If you are interested in planting cherries for your home garden, I’ve included a list of cherries recommended for our PNW climate.  All have good to excellent resistance to blossom brown rot.

14 new cherries will be planted along Azalea Way, Spring of 2014! Thanks to the UW being awarded funds from the Nationwide Cherry Blossom Tree Planting Initiative grant co-sponsored by the Consulate-General of Japan in Seattle and other supporting local community organizations.

Cherry Blossom Brown Rot - causal fungal agent known as Monolinia fructicola. The fungus overwinters on infected twigs and dried fruit on the tree or ground.  The fungal spores are spread in the spring by wind and rain through the blossoms, causing twig dieback.  As part of the UWBG IPM program, moving toward our goal of eliminating the use of all synthetic pesticides is our ultimate goal.

IPM relies on many strategies to manage plant health care. 

  • Proper ID of the pest and its life cycle
  • Regular monitoring of the plants
  • The use of physical, mechanical, cultural, and biological controls
  • Chemical controls used as a last resort*
  • Least toxic chemicals used

* All spray applications are in compliance with WSDA pesticide regulations.  Sign postings are located at all entrances and Graham Visitor Center. Spray applications are scheduled based on timing and weather. We do our best to apply when public are not present. For more information, pls contact, David Zuckerman at 206-543-8008 or dzman@uw.edu

The cherries are pruned in early fall  to remove infected twigs and improve air circulation.  Tree rings are given a fresh coat of mulch in the fall to bury any infected plant material that may be on the ground.  In our Cherry Replacement program we are only using cultivars that are resistant to Blossom Brown Rot.

Cherries recommended for the PNW:

    • Prunus‘Berry Cascade Snow’
    • Prunus ‘Kwanzan’ syn. ‘Sekiyama’
    • Prunus‘Pink Flair®’
    • Prunus‘Royal Burgundy’
    • Prunus‘Shirofugen’
    • Prunus‘Shirotae’
    • Prunus‘Snow Goose’
    • Prunus subhirtella var. ascendens
    • Prunus x yedoensis ‘Shidare Yoshino’
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SPRAY NOTIFICATION: Garden Loosestrife, Initial Treatments July 26 through August 9

July 26th, 2013 by UWBG Horticulturist

photo
UW Botanic Gardens has commenced its 5th and final year of the 5yr Dept. of Ecology, Garden Loostrife eradication project.

Our contractor, NW Aquatic Eco-Systems, has scheduled initial  spray applications to commence on July 26 and continue through first week of August.  There will be a final follow-up application in September.

Postings of project and current spray schedules include:

  • Waterfront Activity Center
  • UBNA kiosk
  • Slough bridge sign in E5 parking lot
  • Yesler Swamp Kiosk
  • UBNA loop trail, east-end
  • All Arboretum boat landings
  • Arboretum Waterfront Trail Entrances (Foster Island and old MOHAI )
  • D.O.T. park-n-ride lot off of 520 Lake WA Blvd exit ramp

Lysimachia vulgaris, Garden Loosestrife, a non-native wetland species is invasive in this area. State listed as a class B noxious weed, it requires control by the land manager UW Botanic Gardens as mandated by King County Noxious Weed Control Board.

Treatment includes:

  •  Approximately 5 miles of shoreline property bordering Union Bay including Foster and Marsh Islands in the Washington Park Arboretum
  • An initial and follow up spray application to occur between July 15 and October 1
  •  Both shoreline and land side application of the herbicide Habitat (imazapyr), a selective broadleaf herbicide.
    •  Non toxic to fish and their food web.
    •  No significant risk to birds or mammals

For more information about this project, please call 206-897-1642 or 206-543-8800.

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Harbinger of Spring in Seattle – Early flowering cherries on Azalea Way!

March 25th, 2013 by UWBG Horticulturist

bird enjoying cherry flowersMost visitors experiencing the beauty of our historic Azalea Way flowering cherries from now through May probably have no idea of how intensive maintaining their health and prolonging their longevity truly is for the UW Botanic Gardens horticulture staff.   Just ask our Integrated Pest manager, Ryan Garrison. Ryan with staff support spends many a day throughout the year monitoring and controlling the numerous diseases and insect pests our 175 plus cherries are prone to suffer from. Our rainy climate doesn’t help one bit either, especially when dealing with our most notable disease during blossom time;  a fungus known as Cherry Blossom Brown Rot. Yucko!  The good news is any new cherries we plant need to show a reasonable level of resistance. The not so good news is many of our older earlier bloomers, the ones extremely susceptible to the brown rot fungus,  need to be protected with fungicide applications during their bloom period.  As with all of our pest issues, we start with cultural and mechanical control efforts before resorting to chemical controls. The following Integrated Pest management (IPM) program discusses our best management practices for the control of blossom brown rot.  If you are interested in planting cherries for your home garden, I’ve included a list of cherries recommended for our PNW climate, all have good to excellent resistance to blossom brown rot.

Cherry Blossom Brown Rot - causal fungal agent known as Monolinia fructicola. The fungus overwinters on infected twigs and dried fruit on the tree or ground.  The fungal spores are spread in the spring by wind and rain through the blossoms, causing twig dieback.  As part of the UWBG IPM program, moving toward our goal of eliminating the use of all synthetic pesticides is our ultimate goal.

IPM relies on many strategies to manage plant health care. 

  • Proper ID of the pest and its life cycle
  • Regular monitoring of the plants
  • The use of physical, mechanical, cultural, and biological controls
  • Chemical controls used as a last resort*
  • Least toxic chemicals used

* All spray applications are in compliance with WSDA pesticide regulations.  Sign postings are located at all entrances and Graham Visitor Center. Spray applications are scheduled based on timing and weather. We do our best to apply when public are not present. For more information, please contact, David Zuckerman at 206-543-8008 or dzman@uw.edu

The cherries are pruned in early fall  to remove infected twigs and improve air circulation.  Tree rings are given a fresh coat of mulch in the fall to bury any infected plant material that may be on the ground.  In our Cherry Replacement program we are only using cultivars that are resistant to Blossom Brown Rot.

Cherries recommended for the PNW:

    • Prunus ‘Berry Cascade Snow’
    • Prunus ‘Kwanzan’ syn. ‘Sekiyama’
    • Prunus ‘Pink Flair®’
    • Prunus ‘Royal Burgundy’
    • Prunus ‘Shirofugen’
    • Prunus ‘Shirotae’
    • Prunus ‘Snow Goose’
    • Prunus subhirtella var. ascendens
    • Prunus x yedoensis ‘Shidare Yoshino’
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RECENT WPA TREE REMOVAL NOTIFICATIONS

October 12th, 2012 by UWBG Horticulturist

This notice is to inform you that the following arboretum trees/UWBG plant collections are scheduled to be removed first half of October. All removals, including public safety and posting details, will be conducted in-house by the UWBG tree crew. 

  • Hazardous mature Fraxinus latifolia, Oregon ash, leaning over Interlaken Blvd in the Holly display
  • Standing dead UWBG plant collection #497-48-C, Cupressus arizonica var nevadensis, Arizona cypress, south Arboretum Dr, across from Pacific Connections – Siskiyou Slope
  • Standing dead UWBG plant collection # X-372-D, Chamaecyparis lawsoniana form, Port Orford, in the Pinetum. Cause: Phytophthora lateralis, systemic soil-borne disease
  • Standing dead UWBG plant collection, Chamaecyparis lawsoniana, Port Orford, in grove across from Graham Visitor Center. Cause: Phytophthora lateralis, systemic soil-borne disease 
  • Standing dead western hemlock, Tsuga heterophylla, located in Woodland Garden

Further questions or comments? Please contact David Zuckerman @ dzman@uw.edu or call 543-8008.

 

 

 

 

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WSDOT Starts SR520 Related Field Study at Arboretum

August 3rd, 2012 by Tech Librarian, Tracy Mehlin

The Washington State Department of Transportation will start geotechnical and cultural field studies at the Washington Park Arboretum near the location of the future 520 bridge on August 6, 2012.

Complete information can be found at the WSDOT 520 Project webpage.

Cultural Resources Fields Study Factsheet

Geotechnical Drilling Field Study Factsheet

 

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WPA Tree Removal Notice

June 26th, 2012 by UWBG Horticulturist

Several standing dead UWBG tree collections are scheduled for removal beginning this week. Removals, public safety and postings, all handled via UWBG tree crew.

The list includes:

  • 225-89-B Cupressus guadalupensis – Pinetum 34-4W
  • 1550-45  Oxydendrum arborea – Rh. Glen 12-7E
  • 52-10  Araucaria araucana – PC Ch. Gateway 1S-4E
  • 164-49-A Acer tegmentosum – Asiatic Maples 27-B
  • 37-02-A Clerodendrum trichotomum – GVC 42-4E
  • 418-55-A Sorbus japonica – Sorbus 20-4E

Thank you,

David Zuckerman

Manager of Horticulture and Plant Records

UW Botanic Gardens

VM 206.543.8008

FX   206.616.2971

dzman@uw.edu

 

 

 

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Cherry Tree Removal at CUH

March 14th, 2012 by Soest Gardener, Riz Reyes

Our row of cherry trees along the driveway at CUH are scheduled to be removed this Thursday, March 15.

Though they’re starting to bloom, we have a severe infestations of blossom brown rot, a common fungal disease of cherries in the Pacific Northwest.

Fungicdal treatments are not a sustainable option. Our decision to display healthy plants available in the trade has left us with the option to choose plants that will be more adaptable to this site.

For more information, check out a post composed by Horticulture Supervisor, David Zuckerman, on the early flowering cherries along Azalea Way in Washington Park Arboretum.

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Notice of Garden Renovation: Soest Garden Specimen Tree

October 4th, 2011 by Soest Gardener, Riz Reyes

Our Persian Ironwood tree slated to be replaced later this fall/winter

So after 13 years in the same raised bed, it’s time that one of our Persian Ironwood trees (Parrotia persica) be removed and replaced with another species.

It was suggested that every ten years or so, the specimen tree would be changed out to showcase different species that could be utilized to create the part shade environment intended for the perennials planted below. There’s also concern that a mature tree’s roots could damage the concrete wall if allowed to get large.

After leaf-drop this fall/winter, we will close off the Soest Garden for a day or so and have the tree removed. Some of the soil will be replace (and perennials moved temporarily, of course) and our new tree, a American smoke tree Continus obovatus, will be planted.

We will begin digging up perennials shortly and keeping them in the nursery until they can be replanted in the same bed. Signs will be posted describing the project and further notice will be made when the date of renovation is determined.

CUH Grounds Staff

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Maintenance Improvement: Azalea Way Gravel Path

August 22nd, 2011 by UWBG Horticulturist
Azalea Way photo

An expansion of the Azalea Way lawn path is proposed.

Historically the Azalea Way lawn path experiences 8-9 months a year that are very wet making access difficult. In 2009 a crushed rock path was added to the middle of Azalea Way from Boyer Parking lot to the Woodland Garden. The proposed improvement will add 700 feet of 6 foot wide crushed rock path from the Woodland Garden to the Lynn Street Bridge Trail.

Parks anticipates the construction of the path will take place over the first two weeks in September 2011. We will work in sections to minimize the impact on users.

The project is funded by generous donation from the Arboretum Foundation.

Thank you for your support and patience during this project. 

For more project information please contact:

Lisa Chen, Park Horticulturalist Seattle Parks and Recreation 206-233-3777 or lisa.chen@seattle.gov

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