11 Pine Trees Spared in Lower Arroyo Habitat Restoration Project

Following what one committee member called a “grueling” meeting, the Urban Forest Advisory Committee voted 4-1 Wednesday to accept a modified version of a Department of Public Works recommendation for a habitat restoration project in the Lower Arroyo.

The committee eventually agreed to remove 61 non-native trees and keep 11 pine trees that were slated for removal in the project’s original project plan.

Of the total number of trees, three different groves were considered separately by the committee. Approximately seven Chinese Elms and eight Eucalyptus were left in the plans for removal, along with seven Canary Island Pines. Those trees stand just north of the Van de Kamp Bridge.

The project will see the planting of 11 Southern California Black Walnut trees, 14 Coast Live Oak trees, 17 Western Sycamore trees, and approximately 2,000 understory shrubs and herbaceous plants.

Committee member Kelley Holmes, of the Pasadena Beautiful Foundation, acting as chair for the meeting, was the only “no” vote for the decision as Mark Mastromatteo, Tim Martinez, Betsy Nathane, and Robert Carpenter voted to remove the majority of the trees as recommended.

According to the Department of Public Works staff report, the trees were proposed for removal in order to restore the native plant communities and associated wildlife habitat in the Arroyo Seco from the area surrounding the John K. Van De Kamp Bridge, and north to the Pasadena Casting Pond.

The plan will “restore, enhance, and reestablish the historical native plant communities of the Arroyo Seco,” the staff report said.

The report also said that the removal of the non-native trees, woody plants and pampas grass is “necessary” to meet project criteria for restorations.

“The removal of non-native species is a core component of habitat restoration,” said the report, adding that “the removals create open areas to allow the native plant species of the region to reestablish themselves. As the plants establish, mature and propagate, the habitat is restored for the local native wildlife and improves the ecosystem health of the area.”

The project was endorsed by the Arroyo Seco Foundation, the Pasadena Casting Club, and by a local petition which contained 500 signatures in support.

Public Works staff will finalize the project plans and specifications in the fall of 2020 and prepare bids to submit to City Council or approval by December 2020. The construction completion date is set for March 21, 2021, in order to comply with a Proposition A grant reimbursement deadline, according to the staff report.

Much of the committee discussion was taken up by a discussion of maintenance of the new trees, with Chairperson Holmes voicing concerns that the project may not contain a maintenance component. Holmes cited the 1997 “BFI Project,” an environmental mitigation project by Browning Ferris Industries, to compensate for the expansion of Sunshine Canyon Landfill in the San Fernando Valley.

According to “Post-Project Appraisal of Low-Flow Channel and Revegetation, Arroyo Seco, Pasadena, California,” by Tanya Patsaouras and Derek Schubert,
“The project … dramatically increased the amount of vegetation in the area, but requires considerable maintenance to sustain. Because of the impermeable liner that lies beneath the low-flow streams and the lack of variable flows characteristic of a natural stream…the restoration program does not sustain the full range of processes of a stream ecosystem.”

Pasadena Department of Public Works Director Ara Maloyan largely agreed with that assessment, and stressed to Holmes and the committee that the Lower Arroyo habitat restoration project would have a “guaranteed” minimum five-year maintenance plan, and would not move forward without it.

Maloyan urged the passing of the project, even modified, saying that, “if we don’t at least vote for this project, we will lose $500,000 in project funding.”