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ARS Home » Northeast Area » Washington, D.C. » National Arboretum » Gardens Unit » Research » Research Project #426365

Research Project: Establish and Maintain Public Display Gardens for Woody and Herbaceous Landscape Plants

Location: Gardens Unit

2016 Annual Report

Objective 1: Collect, propagate, preserve, evaluate, document, display, distribute, and introduce woody and herbaceous landscape ornamentals with enhanced aesthetic appeal, resistance to extreme weather, resistance to pests and diseases, and enhanced ecosystem benefits. Collection activities will focus on native plants due to difficulties with collecting plants in most other countries. [NP301, C1, PS1A] Objective 2: Disseminate scientific and practical information to floral and nursery crop industries, to public gardens, to the increasing number of visitors to the U.S. National Arboretum and its Website, and to the general public interested in gardening. [NP301, C2, PS2B] Sub-objective 2.a. Develop exhibits and interpretive signage that reflect current relevant ARS horticultural research programs, including the scientific mission of the U.S. National Arboretum. Sub-objective 2.b. Develop educational programming to increase awareness of ARS research and germplasm preservation taking place at the U.S. National Arboretum.

The U.S. National Arboretum will continue to serve the public need for scientific research, education, and gardens that conserve and showcase plants to enhance the environment. This will be accomplished by maintaining outstanding gardens, plant collections, and public displays in an environmentally responsible and aesthetically pleasing manner. New ornamental cultivars and germplasm will be acquired using the Collections Policy and the newly developed Strategic Plan as a guide, and in support of the National Plant Germplasm System. Plants will come from nursery sources, wild-collected, or the USNA research program. Plants with superior landscape attributes will be propagated for distribution and evaluation. Staff will continue to utilize integrated pest management (IPM) in management of their collections and will explore the use or demonstration of other technologies such as solar power, green roofs, rain gardens, and water wise gardens as funds allow. Plant records will be updated and coordinated with GRIN-global, and information will be uploaded to the publicly accessible Arboretum Botanical Explorer database. A new exhibit and educational program, GrassRoots, will be put in place. Educational opportunities will be optimized and implemented to provide formal and informal educational programming through exhibits, signs, publications, web pages, lectures, workshops, and tours. Volunteer and internship programs will continue to be supported.

Progress Report
Springhouse Run Stream Restoration and R Street Parking Lot Retrofits: The design work and permitting is now complete for this project, and the District of Columbia Department of Energy and Environment is working on obtaining District of Columbia Council approval for the project. Plants destined to be incorporated in the restored area have been successfully held in the nursery for planting. There is a need to identify long term resources for invasive plant surveillance and removal in this area. Friendship Garden Renovation: Aggressive perennials have been successfully removed and planting is underway. Spring blooming bulbs will be added in October 2016. Support of Entomological Research: Ongoing support has been provided to researchers in the Invasive Insect Biocontrol and Behavior Laboratory in Beltsville, Maryland and the Beneficial Insects Research Laboratory in Newark, Delaware in utilizing the grounds of the U.S. National Arboretum for research related to biocontrol of landscape pests.

1. Management of gardens and collections. Through increased scrutiny of nomenclature and research on sources, the quality of data kept on plants in gardens and collections has improved. Plants of unknown provenance are being removed and replaced with wild collected plants or plants of known origin where possible. Maintenance tasks and labor structuring have been changed to allow for completion of large projects in a short period of time and to reduce the time spent on certain activities such as mowing, mulching, and leaf collection. Many stakeholders and visitors have commented that the gardens and collections are looking better than they ever have.

2. Germplasm acquisition, distribution, and incorporation into collections. A major objective of the Gardens Unit is to enrich the living plant display collections at the U.S. National Arboretum by incorporating documented germplasm into these areas. Collection Development Plans are being drafted for each of the collections managed by the Gardens Unit to guide future acquisitions. A Collection Development Plan has been completed for the Friendship Garden.

3. Evaluation of germplasm. Several plants, including rosemary and dogwood, are being propagated for distribution to cooperators for broader evaluation. Plants collected in the High Plains region in 2010 are being evaluated for use in green roofs and rain gardens.

4. Dissemination of plant information to the public. The nearly half a million visitors to the gardens and collections of the U.S. National Arboretum (USNA) could potentially learn about the work of ARS. The new Arboretum Botanical Explorer has greatly increased public access to the holdings of the USNA.

5. Management of invasive plants. Controlling invasive plants continues to be a major issue on the grounds of the U.S. National Arboretum (USNA). This work helps to preserve existing germplasm in the gardens and collections of the USNA, protects woodland and meadow habitats on the grounds from degradation, and provides a model for management of invasive plants that may be useful for other land managers.