Hoyt Arboretum’s Redwood Renovation Plan is funded and managed by Hoyt Arboretum Friends (HAF).   Expertise regarding plant collection issues and trail requirements is provided by Portland Parks and Recreation (PPR) staff.  The long-term goal of the plan is to restore the beloved and majestic Redwood Collection to full health by reducing overcrowding, adding specimens to increase diversity, and providing irrigation to trees that would normally receive more rain in their natural environment.   In addition, improvements in visitor access and education are planned for the area.

 The Redwood Collection is an 8.5 acre grove of coast redwoods (Sequoia sempervirens) and giant sequoia (Sequoia giganteum), interspersed with other Cupressaceae family members and located on the cooler north-facing slope of the Arboretum.  It is part of the world-renown Conifer Collection that comprises approximately half of the Arboretum.  The majority of the redwood and sequoia trees were planted in the early 1930’s pursuant to then-current forestry practices.   At the time they were only 4’ to 6’ tall.

Now 75 years old and nearly 150’ tall, they suffer from overcrowding which negatively impacts both their health and appearance.  The understory has been restored in recent years but erosion, off-trail foot traffic, and non-native invasive plants are constant threats to the grove.  Other than individual identification labels on each tree, there is no interpretive signage to help visitors understand what they are seeing.  Improvements, long deferred, are now urgently needed.

 In 2006, Phase I of the Redwoods Renovation Plan was completed when the firms of Ceccacci & Associates and Koch Landscape Architecture developed a Redwoods Renovation Concept Plan for the Arboretum.  This is a comprehensive development plan for improving

~ public access and understanding of the collection through trails, visibility of trees, and interpretive signage
~ protection strategies for the existing collection and future additions.
~ age and species diversity of the collection.

 
~  Site Plan for the Redwoods Renovation 

 


~  Site Sketch 

 ~ Project Illustration

In early 2007, the Initial Implementation Phase (Phase II), will begin when several of the trees in the Redwood grove will be removed in order to create sufficient growing space for the healthier trees.  This “weeding out” process, intended by the original planters to occur at regular 10-year intervals, has never been done before.  The trees that will be removed have been carefully selected as the least healthy, least viable of the group.  Their removal will allow the healthier trees to spread their canopies to absorb more sunlight and their roots to absorb more water and nutrients so that 75 years from now there will still be a beautiful, and even bigger stand of coast redwoods to marvel at in the Arboretum.   In Redwood terms these trees are still babies with limited commercial value but much of the wood salvaged will be used by the Arboretum to construct new trail railings to protect fragile areas and trees.

 In the coming years HAF will be working to develop funding for this project which will serve as a model for renovation that is needed throughout much of the Arboretum.  Other phases in the Redwoods Renovation Plan  will address the following improvements:

~ an irrigation system to mimic the native habitat’s  “summer rain” climate.

~ repositioning of trails to provide better wheelchair access and a loop route.

~ ongoing removal of non-native invasive plants and maintenance care for the existing trees.  Providing an understory of swordfern and other appropriate plants.

~ adding viewpoints and decks for visitors and school groups to congregate, rest and see the trees more closely.

 ~ new plantings of other related Cupressaceae family species, including some endangered species, and younger pedigreed specimens.

~ adding retaining walls, trail railings and small bridges to prevent erosion and protect the trees’ root systems.