The following was forwarded to David P from HRM Councilor & PPP Advisory Committee member Waye Mason in response to David’s request for info about the thinning (tree culls) planned at PPP, which had been highlighted on CBC.
Waye Mason requested and received comments on the info.
From: Tapper, Alana
Sent: Wednesday, May 15, 2019 1:25 PM
To: Mason, Waye <Waye.Mason@halifax.ca>
Cc: Rice, Stephen <ricest@halifax.ca>; Walsh, Ray <walshr@halifax.ca>
Subject: PPP Thinning Information
Good afternoon Councillor
Steve Rice and I discussed and based on the initial Director’s Briefing Note in 2018 explaining the project objective, the plan is to go back through these thinned sites in approximately 3-4 years after the initial thinning to do another lighter secondary thinning. This secondary thinning will focus on any new or missed invasives. Regular monitoring will be done throughout the 3-4 year time period between thinning. As indicated in the Comprehensive Plan results will be monitored and, if necessary, adapted to ensure the work is not counter productive. I have included excerpts from the briefing note below.
The current thinning work will open up growing space, but it will benefit the trees that are left more than permit space for invasive species to grow. It usually takes 2-3 years to see any response growth and by then we should be in a regular routine of monitoring. I have complete faith in the proposed 10 year plan Steve has developed and understand that with regular monitoring, we could adapt our response should we see another invasive species start to develop a strong hold in the area.
Also, as part of the current thinning, we are addressing invasive species that are more problematic than Multiflora rose . Norway maple is capable of transforming the entire parks ecosystem as it could take over and form a monoculture. We will be removing hundreds, if not thousands, of invasive plants like these during the thinning program.
I hope this information is helpful, please feel free to contact Steve or I if there are any further questions.
Thanks
Alana
BACKGROUND
In September 2003, Hurricane Juan destroyed nearly 75% of the forest within Point Pleasant Park and due to the threat to public safety it was closed until June 2004. Although quite devastating at the time, it ultimately provided an opportunity to reset the focus of the park. In January 2005, public discussion began on the most effective ways to restore the park. Through a private donation the Municipality developed the Point Pleasant Park Comprehensive Plan, which was adopted by regional council in October 2008.
One of the core recommendations from the Comprehensive Plan called for a forest work plan to guide re-establishment of the parks Acadian forest. It outlines key objectives to re-establish and manage the forest within Point Pleasant Park. This plan was developed in conjunction with the Comprehensive Plan and was finalized in November of 2008.
The Forest Work Plan identifies the parks forest condition post-Hurricane Juan and provides recommendations to direct future growth and meet several of the goals outlined in the Comprehensive Plan. It gives special consideration to archaeological and wetland areas, as well as providing management options for dealing with non-native invasive species. The overall theme of the Comprehensive Plan can be summarized by “the park forest must be managed for resilience to future disturbance agents”.
DISCUSSION
Since adoption of the Forest Work Plan adoption in 2008, several forest restoration projects have been completed:
- From 2008 – 2009 over 100,000 seedlings have been planted in areas where trees were not naturally re-growing. This exceeds the number of trees that were lost during Hurricane Juan in Point Pleasant Park.
- In 2010, several large trees were removed from fortifications to help reduce further damage to historical assets and to prepare for restoration projects.
- Trials for removal of invasive plants were conducted and information gained from those trials will be used to develop control strategies over the next 10 years. Species targeted were multiflora rose (Rosa multiflora) and Japanese knotweed (Fallopia japonica).
In areas affected by Hurricane Juan, natural regeneration of the forest has been impressive. This regeneration has reached a point where intervention is required to thin out overcrowding allowing trees to become more open in their growth habit and to be more wind firm. A secondary benefit of this thinning, is to eliminate exotic and invasive tree species. In commercial forestry, this practice is known as pre-commercial thinning, but for our purposes it is best referred to as stand enhancement thinning (SET).
Stand enhancement thinning (SET) will be done in two phases:
Phase 1 – will space the trees 2.5 – 3.0 meters apart while incorporating the removal of all non-native invasive species. Trees such as red maple that have regrown numerous stems from suckering will be thinned down to 3 – 5 main stems and will require successive thinning in future years.
Phase 2 – will commence approximately 5 years following Phase 1. This thinning will focus on the trees that were reduced to 3 – 5 stems, and will thin to a final single dominant stem. Any non-native invasives that may have been missed or are re-growing will also be targeted.
Other objectives that can be completed within the scope of work include:
- Selective removal of mature invasive trees such as Norway Maple and Scots Pine.
- Selective removal of trees to protect fortifications and maintain historical view planes.
- Removal of highly invasive multiflora rose and Japanese knotweed.
- Reclamation of forest stands through removal of crusher dust migration into forest areas.
PROJECT DETAILS
Develop a detailed 10 year plan for the following five projects:
1. Stand Enhancement Thinning (SET) – GPS areas, measure height stratums, produce maps and amass information for tendering. Develop methodology, i.e. Goal is a 50-50 ratio of softwood to hardwoods on flat surfaces, 30-70 ratio of softwood to hardwoods on south facing slopes, spacing factor, list of desired species, buffers around wetlands. This work can be completed using internal and external resources.
2. Reinstatement of one Heather stand – by removing woody and herbaceous materials so area in made up entirely of heath and heather species. This work can be completed using internal resources.
3. Invasive tree removal – GPS locations, create a current map of mature invasive trees and develop a 10 year schedule for their removal. Plan identifies 19 different native trees and 15 non-native tree species. This can be done using internal resources..
4. Tree removal from fortifications – Develop a current map of trees on fortifications requiring removal and develop plan. Revegetation may be required. This can be done using internal resources.
5. Invasive plant removal – Develop prescriptions for removal of Japanese Knotweed and multiflora rose. Disturbed areas will have to be covered with mulch and re-planted. Knotweed may require complete excavation and removal.
6. Removal of crusher dust – Update existing map, develop a scope of work and schedule for removal and reinstatement of vegetation.
ALANA TAPPER
SUPERINTENDENT PARKS WEST
PARKS & RECREATION
HΛLIFΛX
T 902.490.6534
C 902.222.1499