Nickel Bottom Garden: Conservancy Project

The focus of the Zonolite Conservancy Project can be summarized in four words – remove invasives / encourage natives.  The predominant forest understory of Zonolite Park consists of invasive plants.  The invasive plants have overwhelmed the ecosystem of the forest and crowded out native plants.  The objective of the project is to significantly reduce the invasives in the park, support the native plants present in the park so they can again thrive and supplement the native plant population with additional plantings of native plants, if required.

The invasive plants most predominant within Zonolite are; Chinese Privet, Bush Honeysuckle, Japanese Honeysuckle Vine, English Ivy and Japanese Hops Vine. Several actions have been taken or are planned;

  1. bi-weekly a team of volunteers cut Privet and Bush Honeysuckle with the cuttings picked up by the Atlanta Zoo to feed the animals – you can see the work of this team as they have cleared the area to the left of the bridge and the creek and along the path to the beach
  2. volunteer teams have removed much of the invasives within the “loop”  – the brush piles are a monument to their efforts
  3. we have contracted with a vendor to remove invasives – you can see their work along the creek and in other spots in the park
    The volunteers will continue to cut twice a month for the Zoo.  As budgets allow – we will supplement that effort with contractor services.  The intent is to get rid of the invasive plants to allow native plants to grow.  The removal of the majority of invasives will take several years.  This is not a one-time effort.  The objective is to significantly reduce the number of invasive plants – not eliminate them in total.

Why Restore the Zonolite Forest

There are many reasons to restore the Zonolite Forest – beyond our basic enjoyment of this unique and wonderful  space.  The New York City Guidelines for Urban Forest Restoration summarize the value of reforestation nicely.

“Urban forests are a critical part of the city’s green infrastructure, providing an array of ecological services and opportunities for recreation. Healthy forest ecosystems can cool peak summer temperatures, absorb and filter storm water, absorb air pollution, release oxygen, store carbon in vegetation and soils, and support biodiversity, as well as allow city residents respite from the frenzy of urban living. Degraded forests exhibit diminished capacity for providing these functions.”

Why Focus on Native Restoration

Native plants support biodiversity and create sustainable environments for wildlife.  A native environment assists with climate change, provides a healthy place for recreation and allows us to walk in a beautiful place.  The Georgia Extension Service in their bulletin entitled  “A Complete Guide to Native Plants of Georgia” defines the benefits a native plant community provides:

  • space for birds and other wildlife
  • a casual stroll through a woodland setting teeming with ever-changing flora and fauna is a relaxing and peaceful diversion from our daily lives
  • “watchable” wildlife habitats – native butterflies, insects, birds, mammals, reptiles and other animals evolve with the native flora and are sustained by it year round
  • a sense of place, fostering appreciation of our natural heritage and the diverse beauty of unique regional landscapes
  • adaptations to local climate
  • ecological preservation
  • habitat protection and preservation – that are an obligation of all Georgia citizens

Why is Zonolite Cutting Down Trees and Shrubs

The trees being cut down are Chinese Privet.  The shrubs being cut are Bush Honeysuckle.  Privet and Bush Honeysuckle are preventing a natural understory to grow among the mature trees.  The intent is to remove much of the invasive Privet and Bush Honeysuckle to allow native plants to grow.  The area that has been cut along the South Fork trail has revealed small native trees growing – maybe 12-18 inches high.  Over time, in the absence of Privet and Bush Honeysuckle, these small native trees will hopefully grow robustly.  Removing Privet will also make many of the existing beautiful trees accessible – as they are currently hidden behind a Privet wall.

Once the majority of the invasives have been removed, we will allow the native plants to grow for a few years, with taking minimal or no actions, so we can develop an understanding of what planting may be appropriate to supplement the natural growth – if any.

How Come the Park Within the Loop is Being Planted Like it is a Garden and not a Forest

The loop is a transition area.  This area had many invasives – a significant amount of Privet was removed.  Kudzu and Japanese Hops Vine have been removed along the smaller creek.  These actions left open spaces in the tree canopy.   Much of the planting in this area has been native trees with an intent of improving the understory.  The long-term goal for the loop is for a healthy urban forest, not a garden.  Other restoration projects have identified the development of an understory as an important action – to minimize the growth of other invasives (to avoid removing one invasive to be replaced by another).  The NYC Guidelines for Forest Restoration, at the below link, provides additional information about the importance of developing an understory.

Helpful Links

The below links provide additional information related to urban forest restoration.

A Complete Guide to Native Plants of Georgia is great resource for native Georgia trees, shrubs and vines.

The below website for “Natural Communities of Georga” is a website, associated with a book of the same name, that has a vast amount of information related to native plants across the ecoregions of Georgia. Natural Communities of Georgia

New York City’s “Guidelines for Forest Restoration” is a useful resource.  The guidelines are; “a compendium of the theories and practices developed, implemented, and tested during thirty years of natural area restoration by the New York City Department of Parks & Recreation’s (NYC Parks) Natural Resources Group (NRG).”

The below research studies, look at the NYC experience and the effectiveness of the approach and practices defined in the above NYC guidelines.  One of the authors participated in both studies.  The studies conclude most of the forest restoration projects achieved the primary goals of their projects.  However, what makes the studies interesting are they propose the objectives of urban forest restoration projects need to consider the current state of the forest, what is reasonable to achieve, and not have an objective to turn the park back to a “pristine” state.  The project objectives should focus on achieving the benefits provided by a  “native re-forestation.”

Restoration in Urban Parks: Long-term Tests of Forest Management to Advance Landscape Structure and Function | 2015 ASLA Professional Awards

The Georgia Forestry website has an abundance of helpful information – including a section dedicated to, “Urban and Community Forestry.” Georgia Forestry Commission

The US Forest Service’s “A Field Guide for the Identification of Invasive Plants in Southern Forests” is a good guide to help you identify invasive plants – as the guide includes several pictures, at different times of the year, of many of the invasive plants.

Zonolite has many invasive plants included in Trees Atlanta top 10 available at this link. Top 10 Invasive Plants That Harm our Urban Forest | Trees Atlanta

This document defines proven strategies for stream restoration in Georgia. (PDF download)