As part of the Precision Silviculture Programme within Forest Growers Research, a trial to test a seaweed-based hydrogel was set up by a team from Scion together with Timberlands and contractor, H.A.Fear. The hydrogel was applied, and the trees planted, using a mechanical ‘M-Planter’ in Tarawera Forest in March 2022.
The site was renowned for its dry, difficult establishment conditions. On this occasion the hydrogel had no significant effect on tree survival, and only a minor positive impact on early growth, perhaps because the weather was unusually wet around planting time. The results from this first trial were outlined to local foresters as part of the ForestTECH 2022 series, both in New Zealand and Australia, that ran in November last year.
A second similar trial was planted with the M-Planter in December 2022 in collaboration with Rayonier-Matariki Forests to see whether hydrogel would increase survival over drier summer conditions. Again, the trial was compromised by unseasonably wet weather, however, the team learned a lot about the operation of the M-Planter in wet weather and clay soils.
The final report on the project can be read here.
A fundamental research trial on hydrogels, that removes the vagaries of the weather will continue because their use is closely aligned with mechanised planting. Extending the planting season is key to increasing planting machine utilisation, thereby improving the overall cost-effectiveness of mechanised operations.
Source: Forest Growers Research