Native plants flourish

The speed at which native bush is regenerating in the Avon River red zone is a real shot in the arm for Christchurch, says the Avon-Otakaro Network.

AvON was commenting on findings by Lincoln University professor of urban ecology Glenn Stewart that "the regeneration of native species has been rapid and, in some situations, prolific" in the Avon River residential red zone.

Professor Stewart said in a blog on The Nature of Cities website, that a sample of more than 100 properties throughout the red zone showed birds were dispersing native seed, and seedlings were taking hold.

"Substantial planting of native trees and shrubs in city residential gardens over the last several decades has provided a seed source for this regeneration," Professor Stewart wrote.

The distribution of plants showed a real diversity between coastal areas further inland. "For example, the dioecious shrub Coprosma repens (naturally a coastal species) was more prevalent close to the coast. Prior to the earthquakes this species would not have been as common as it is not regularly planted in residential gardens. But after property abandonment it is increasing rapidly as a result of natural successional processes."

Professor Stewart said early indications were that the native flora of the Avon River red zone was "remarkably resilient". "So much so that it seems certain that in the absence of human interference a substantial native-dominated urban forest will establish in the residential 'red zone'."

"This is really sensational news for Christchurch," said AvON co-chairman Evan Smith. "It shows that our city's environment is truly robust, and if we work with it rather than against it, it will provide us with natural assets that add real value to our lives."