I have calculated this credit for a few projects and am sharing my comments:
- Overall the calculator is easy to use. On urban projects with limited landscaping area, it can be challenging to earn the open space and habitat credits. So it is nice to have this pilot credit as a way to earn credit for increasing planting over existing conditions. Through the calculation exercise I am finding that even when the project is greatly increasing the density/building footprint over existing conditions, it is also increasing the quality of planting (e.g. replacing turf grass with trees and shrubs).
- The i-tree calculator is fairly comprehensive but is missing a lot of shrubs and also some Southwest native plantings (from a project in Austin TX). I was able to show compliance with just trees, but could be an issue for projects with fewer trees and more shrubs. Especially where trees are not the most suited to the environment, the project team might need to find a different calculation tool.
- I don't think I would use this credit or the calculator in making design decisions, but I'm happy to see them line up with design decisions that were made for the pedestrian experience, shade, and visual interest.
Deborah Lucking
Director of SustainabilityFentress Architects
LEEDuser Expert
258 thumbs up
March 7, 2023 - 12:06 pm
Thanks for this Emily.
We registered for this pilot when it first came out, and had a real challenge with the i-tree calculator. We put off attempting the Credit for that reason. Your post is encouraging!
Sarah Linke
Green Building ConsultantGreenwood Consulting Group
16 thumbs up
May 22, 2023 - 4:36 pm
Emily, we learned of this Pilot credit at GreenBuild 2022 and it has been on my list of Pilot credits to investigate. I agree with you on the shrubs being missing, but overall- the Landscape Architect was able to navigate the tool although he had never used it before.
Michelle Halle Stern
Senior Sustainability ConsultantGreenwood Consulting Group
120 thumbs up
November 2, 2023 - 1:03 pm
We're pursuing this credit but being challenged with the caliper of the new trees versus the existing trees. The proposed case has significantly more trees than the base case, but the existing trees to be removed are more mature. Do the new trees need to be counted as if they are saplings or can we choose a point in time when they are more mature?
Summer Minchew
Managing PartnerEcoimpact Consulting
LEEDuser Expert
170 thumbs up
February 2, 2024 - 2:15 pm
Michelle - We use the average diameter of the mature tree trunk not the caliper at planting.
Deborah Lucking
Director of SustainabilityFentress Architects
LEEDuser Expert
258 thumbs up
February 2, 2024 - 2:59 pm
FWIW we submitted this as an Innovation Credit under Sustainable SITES (I believe submission requirments are similar).
The Baseline site was a brownfield resulting from several cleared buildings and parking lots without any existing plantings within the LEED project boundary. The project boundary was along the sidewalk bounding the project site.
I-Tree did not have the option for creating a report without plantings, thus 15 trees located in the public right-of-way were used for the Baseline report. The project ended up REMOVING these 15 existing trees, and replanted with 27 new trees, and approximately 700 shrubs. As these were outside the SITES boundary the project team elected NOT to consider these trees and shrubs.
Also several of the selected shrub planting types were not within the i-Tree database, and therefore 676 shrub plantings were not included in the proposed design analysis.
We did manage to achieve the Credit. Not the most rigorous of processes, but we'll take the Innovation point.
SITES also pointed us to some resources: the i-Tree Forum FAQ's (https://forums.itreetools.org/viewforum.php?f=38) and utilizing the i-Tree User Forums (https://forums.itreetools.org/index.php) to troubleshoot this issue within i-Tree's software
Candice Rogers
PresidentPaladin, Inc
21 thumbs up
June 12, 2024 - 10:02 am
We are submitting this credit for a project that specializes in ag research. They have an on-site arboretum and this credit aligned with the project goals. We did not find the iTree inventory lacking - but that is due to the nature of the plantings (trees) we are incorporating.
Thomas Lagarde
September 20, 2024 - 10:06 am
Any feedback on the description ?
Option 1. Increase Onsite Carbon Sequestration (1 point)
I wonder what kind of argument presentation they are looking for.
Thank you
Sha Alan
HibouairSeptember 20, 2024 - 12:26 pm
"Thanks for the helpful discussion on the pilot credit. We're currently working on a project with similar challenges, especially around calculating tree maturity and including shrubs not listed in the i-Tree database. It's great to see the strategies others have used to overcome these hurdles. I’ll definitely explore the suggested resources and forums to further troubleshoot. Looking forward to more shared experiences!"
Emily Purcell
Sustainable Design LeadCannonDesign
LEEDuser Expert
370 thumbs up
September 23, 2024 - 6:03 pm
@Thomas so far I have used existing conditions as baseline and as-designed as proposed. I didn't write up a justification as I think this would be the default approach and it was approved. I'm guessing if you had a baseline case similar to the outdoor water use prereq/credit, like typical practice to compare your as-designed case to, you'd need to explain the landscape design you chose for that case.