Managing planting season disruptions

RESEARCH COMMISSIONED INTO TREE PLANTING IN RESPONSE to the COVID-19 lockdown and potential disruptions to the One Billion Trees planting projects and the wider sector, provides welcome solutions to problems with which foresters and planters are all too familiar, says Te Uru Rākau – New Zealand Forest Service.

“The newly-published research has enabled us to come up with strategies to successfully plant trees outside of the normal planting season, and also have a better understanding of how to safely hold back trees in nurseries without impacting the quality,” says Emily Telfer, Programme Delivery Manager, Forest Science at Te Uru Rākau.

With tree planting normally carried out in the middle of the year, significant work is required in nurseries leading up to winter to prepare a crop of trees and by landowners to prepare sites for planting.

“The yearly forestry planting cycle follows a sequential series of steps and is driven by biology, so the research set out to look at what mitigations can be utilised when the sequence is disrupted,” says Ms Telfer.

Managing disruptions to a planting season, site maintenance when planting is delayed, and ‘right tree, right place’ in an extended planting season were some of the topics covered in the research.

Ms Telfer says while the bulk of the research was undertaken as a response to the disruptions caused by COVID-19, the outcome is a package of new understanding which will be invaluable for tree planting in New Zealand.

“Disruptions to a planting season can have major implications, especially when you consider nurseries are carrying 50-60 million seedlings heading into a planting season to meet planting demands.

“If we need to delay plants leaving the nursery, there are a number of techniques which nurseries can use to keep plants in good health until the time they can be dispatched and planted.”

The research explored innovative approaches to manage sites that are unable to be planted in a season, including ways of increasing site fertility to increase the success and health of trees once they are able to be planted.

Among the options looked at were the potential to apply nutrientrich waste like treated dairy shed effluent and wastewater, and site preparations that made the most of existing slash to protect new trees from drying wind.

The One Billion Trees Science Extension team, in partnership with the Canopy Website team has summarised the key research findings into easy-to-read factsheets. The factsheets are based on work by researchers at Manaaki Whenua, Scion and Tane’s Tree Trust, and are available at Canopy.govt.nz