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Yellowstone Arboretum

Prunus Triloba "Multiplex"

An early bloomer found near the Amur Tiger viewing area

"Spring and Getting Down to Business"

Plans are being implemented to make 2023 a busy year for the arboretum and volunteers. After the success of new introductions of Japanese Maples in the Sensory Garden and Chris' garden, the arboretum will be planting more in the newly developed Wolf Gardens. They will enhance the fall season tulip plantings with an extended color season. These tulips will be selected for spring bouquets that will be sold in the visitor's center with all proceeds going to the Zoo. And as a part of the AZH grant, shrub roses will be planted as a compliment to the Foster Waterfowl Refuge. These will be located along the pathway and wall between the River Otter viewing areas.


2023 Oak Tree Initiative Project - UPDATE

The Yellowstone Arboretum has received a Program Development Grant from the Montana DNRC for the purpose of promoting Urban and Community Forestry in Montana. This grant will be used to further the conservation and planting of the species Quercus or as we know it the Oak tree.


Unexpected additions to the program was the acceptance of the arboretum into the GCCO, Global Conservation Consortium for Oaks, and acceptance to the International Oak Society and the Nature Conservancy. The arboretum has received acorns from the community and volunteers, that are being prepped for experimentation and eventual planting. Oak seedlings will also be planted as part of the program.

The Global Conservation Consortium for Oak brings together the world’s oak experts, conservationists, and the botanic garden community to ensure that no wild species of oak becomes extinct.

No one garden or arboretum can or should conserve all of the world’s threatened oak species, so a coordinated, global effort is needed. Led by the Morton Arboretum in collaboration with BGCI and dozens of other partners, the Global Conservation Consortium for Oak was launched to prevent extinctions and ensure healthy oak species and populations for the future.

The goal of the Global Conservation Consortium for Oak is to mobilize a coordinated network of institutions and experts who work collaboratively to develop and implement a comprehensive conservation strategy to prevent the extinction of the world’s oak species.


And speaking about Oaks......

The "Alzada Oaks" constitute Montana's only known stand of bur oak, and the stand lies at the westernmost edge of the species' natural range. They have been affected by mining, associated road construction and maintenance, and grazing (Vanderhorst et al. 1998). The long history of grazing by sheep and horses and the harsh environment at the site favor high numbers of introduced species and a relatively impoverished native flora (Heidel 1993). Competition from weeds may limit the establishment and growth of bur oak. Bur oak provides forage for cattle and mule deer though effects of grazing on the the Montana population are not known. Fire may have played a role in maintaining Q. macrocarpa by reducing competition from non-stump sprouters such as ponderosa pine and juniper, and suppression of wildfire may be having an adverse effect on Q. macrocarpa recruitment.

Citation for data on this page/website:

Bur Oak — Quercus macrocarpa.  Montana Field Guide.  Montana Natural Heritage Program.  Retrieved on February 26, 2023, from

New Affiliation

The Yellowstone Arboretum has been accepted as an affiliate with the Global Conservation Consortium for Acer (Maple). This acceptance partners the arboretum with other major arboretums in collaboration with national acer programs and research.

Led by the University of British Columbia Botanical Garden, in collaboration with BGCI and other partners from across the genus’s range, The Global Conservation Consortium for Acer has been initiated to address the conservation needs of wild Acer species.

The goal of the Global Conservation Consortium for Acer is to mobilise a coordinated network of institutions and experts who work collaboratively to develop and implement a comprehensive conservation strategy to prevent the extinction of the world’s Acer species.


The Yellowstone Arboretum is proud to announce it's affiliation with the International Oak Society.

Since 1992 the International Oak Society has been bringing together oak enthusiasts from around the world. Born from a shared desire to exchange Quercus seed, the IOS has grown in many directions. Our mission: to further the study, sustainable management, preservation, appreciation and dissemination of knowledge about the genus Quercus and its ecosystems.


 New network !

In response to our always changing climate and environmental concerns the arboretum is pleased to announce our connection with the National Phenology Network and their reporting network, Nature's Notebook. The arboretum will be joining two of the network's programs, one for Oak (Quercus) and the other for Eastern Redbuds (Cercis canadensis). A bi-weekly program has been adopted with information going to the national database to track the phenology of these species.



Lewis & Clark

Meet the explorers !


Meet the Early Bloomers

Be sure to check out all the articles in our feature presentations located on the main page of this website. This quarter we feature Montana Oaks,  early bloomers and spring tree care. Click here for more

Keeping Your Trees Happy & Healthy.png


Orientation Meeting

All arboretum volunteers, old and new, are welcomed to attend an orientation meeting

Saturday March 4, 9:00 a.m. in the ZooMontana basement conference area. The meeting will be followed by a walk through of the arboretum and a look at the 2023 programs.

Anyone and everyone invited !

2023 Volunteer Opportunities !

Inventory Specialist (filled)

Relief Hydrologist (partially filled)

Foster Refuge Gardeners (partially filled)

Soil Tester (Open)

 If interested just go to the volunteer page on this website and fill in the simple form or contact Scott at


The arboretum in collaboration with local entities will participate in the move of a 40+ year old Ginkgo tree from the front of the Elks Club to ZooMontana. The Elks building is slated for demolition with the construction of a new residential development. The developers are planning community involvement in the move of this unique tree. Watch for more information as it becomes available. We are looking at a possible Arbor day celebration.


Tree Board Retreat

Members of the arboretum will be participating in the 2023 Montana Tree Board Retreat in Choteau on March 14-16.

The retreat brings tree professionals, volunteers, community officials and state departments together to train attendees and promote trees in Montana.

The arboretum is now listed as a Homegrown National Park. Your native garden can also become a member. Check out the information below:


Meet the Arboretum

Interested in an entertaining and informative meeting for your group or civic organization ? The arboretum is available for just that. Recent meetings with the Audubon Center and Kiwanis Club have had excellent turnouts. Your organization could enjoy the same.

Contact Scott at:

406-860-3160 or email at:

Click here to see slideshow presentation


A unique donation will soon be on display in the Homestead Collection. This cart is a mail wagon used by the U.S. Postal Service during the early part of the last century in Hardin, Montana. Plans are that it will be on display with a flower collection and signage this coming season and will be located behind the Homestead barn. Check it out !


"The mission of the Yellowstone Arboretum is to cultivate arboreta appreciation and understanding of our local heritage through public education, organic preservation and stewardship of our natural environment."





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