March 25th, 2011 by UWBG Horticulturist
Most 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, pls contact, David Zuckerman at 206-543-8008 or firstname.lastname@example.org
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’
October 26th, 2010 by Tech Librarian, Tracy Mehlin
WSDOT’s SR 520, I-5 to Medina Project: Section 6(f) Environmental Evaluation comment period will be ending on Wednesday, December 8, 2010
The preferred alternative selected for the SR 520, I-5 to Medina: Bridge Replacement and HOV Project will convert properties protected by the Land and Water Conservation Fund (LWCF) Act of 1965. The Federal Highway Administration (FHWA) and the Washington State Department of Transportation (WSDOT) have prepared a Section 6(f) Environmental Evaluation in accordance with the LWCF Act Section 6(f)(3). This document evaluates the effects of converting recreational properties (e.g., parks) protected by Section 6(f) to non-recreational use and replacing them with property of at least equal fair market value and of reasonably equivalent usefulness and location. The Section 6(f) protected properties proposed for conversion are portions of the Ship Canal Waterside and Arboretum Waterfront Trail complex, and portions of two associated parks, East Montlake Park and the Washington Park Arboretum. The Section 6(f) Environmental Evaluation will be available for a 30-day public comment period beginning in early November 2010.
Please check back in early November for a link to the document and comment form. For more information on the SR 520 Bridge Replacement and HOV Program, please visit the project website at
August 26th, 2010 by UWBG Horticulturist
Eurasian berms are located at far right - in pink
September through October is our window of opportunity before fall rains begin to commence development and improvement work in the Holly collection. Scope of work during this period will focus primarily on construction of the southernmost Eurasian clade berm located at the north end (near Boyer Ave). See photo of Iain Robertson’s conceptual Holly collection plan – Eurasian clade berms are pink.
- In-house tree removals – 4 small undesirable Bigleaf maples and 4 maple stump sprouts
- Contract tree removals – 6 cottonwoods and 1 Western red cedar
- Also, removal of 4 collection hollies in very poor condition in existing Eurasian berms
During this project work, area will be cordoned off to public and if needed, pedestrian detours will be established.
Project info will be posted at work site and at the Graham Visitors Center.
Beginning in late October 2010, regional Qwest corp, will begin a new partnership with UW Botanic Gardens and Seattle City Parks and Recreation. Under the guidance and training of UWBG horticulture staff, Qwest volunteers, known as Pioneers, will ultimately ”adopt” the Holly garden for a year in all facets of horticulture care and maintenance. Initial tasks will focus on:
- Finishing southernmost Eurasian clade berm construction if weather permits - grubbing, grading, soil work
- Modification of northernmost Eurasian clade berm – adding more soil to raise profile and improve drainage
- Plant and care of several new holly collections, mostly Eurasian clade members
- General maintenance (weeding, mulching and edging) of the entire Holly garden, including native restoration sites
We look forward to our new partnership with Qwest Pioneers and a marked improvement of our Holly garden.A project sign will be installed on-site in the next few weeks by Seattle City Parks and Recreation.
August 13th, 2010 by UWBG Horticulturist
Garden Loosestrife (GL) control contractor, NW Aquatic Ecosystems, along with UW Botanic Garden IPM staff, will complete initial 2010 treatment on Wednesday, August 18th. The Waterfront Trail between Foster Island and MOHAI will be closed early am to public temporarily for contractor access to GL growing near the trail. Signs will be posted on barricades at both trailhead entrances and also staffed during spray period to avoid public breaching the barricades. Trail will be reopened once material has dried on foliage. The remainder applications will be accomplished via boat in and around Marsh and other islands and inlets throughout UW Botanic Gardens managed Union Bay shorelines.
Scheduled pm Kayak tours will not be disrupted. Applications within tour boundaries will be completed in am.
There will be a follow-up treatment later in September. Notice will go out as soon as date is set.
For further information, call 206-543-8800
August 5th, 2010 by Tech Librarian, Tracy Mehlin
Help us get the word out about the many fun events and classes offered by UW Botanic Gardens. The primary responsibility is to submit event details to media and community web calendars.
Bi-weekly commitment, 2-3 hours per day, 2-3 days per month.
Contact: Jean Robins, Continuing Education Coordinator, 685-2590 or email@example.com
August 3rd, 2010 by UWBG Horticulturist
ARBORETUM TREE REMOVAL NOTICE –
UWBG tree crew has scheduled the removal of a large standing dead pine collection for Wed. 8/4. Details below:
Pinus strobus 977-97-E
Tree has been in decline for several years, possibly due to drainage problems and/or root rot.
Wood will be hauled and stump ground ASAP to minimize attracting pine pests.
Targets include Pinetum Loop trail and other and other plant collections.
Temporary road and trail closures and/or detours will be well marked at the site and removal posted at the Graham Visitors center. Thank you for your cooperation.
If you have any questions, please contact me via e-mail or phone number below.
David Zuckerman, UWBG Horticulture Supervisor, 206-543-8008
July 29th, 2010 by UWBG Horticulturist
For a second year, Northwest Aquatic Eco-Systems along with UW Botanic Garden will begin spray work to control Lysimachia vulgaris (garden loosestrife), a state-listed noxious weed occurring along Union Bay shorelines including the Union Bay Natural Area and the Arboretum’s Foster and Marsh Islands the first week of August. King County requires control of this aggressive and invasive weed, which poses a serious threat to the native character of area wetlands. In 2009, DoE provided a 5-year grant for $75,000 to fund loosestrife control.
In mid-July members of King County’s Noxious Weed Control Program and UW Botanic Gardens staff mapped the extent of the weed in the areas listed above. Comparison of the maps from year 1 to year 2 demonstrated slight control had taken place. Once again the weed will be controlled with an aquatically approved herbicide by the contractor, Northwest Aquatic Eco-Systems using airboats and other specialized equipment.
King County Garden Loosestrife Fact Sheet
July 28th, 2010 by Tech Librarian, Tracy Mehlin
The Washington State Department of Transportation (WSDOT) is conducting a cultural resources study on Foster Island as part of the I-5 to Medina: Bridge Replacement and HOV Project. This important safety and mobility project will build a safer floating bridge and give new options to people crossing Lake Washington.
Foster Island Study Fact Sheet
March 26th, 2010 by UWBG Horticulturist
Upcoming Pacific Connections Phase 2 Construction
33 trees will be removed under the Pacific Connections Phase 2 Project. These trees do not contribute to the horticultural collection. They are being removed as a management tool and to make way for the new Chilean garden.
Location: Pacific Connections Garden – Chilean Immersion Forest NE quadrant of intersection of Lake Washington Blvd. and Arboretum Drive.
Timeframe: April 19 -23, 2010
Safety: Service roads and trails near tree removal operations will be clearly signed “Closed” for this removal and a detour will be set up to route pedestrians around the removal.
Contact: Andy Sheffer, Seattle Parks and Recreation, for additional information. firstname.lastname@example.org or 206.684.7041
November 19th, 2009 by UWBG Communication Staff
The Arboretum and Botanical Garden Committee has issued guiding principles for the Washington State Department of Transportation project of replacing the State Route 520 floating bridge.
For complete information on the project and to make a comment go to the WADOT website for SR 520.