Various scarification treatments produce different regeneration potentials for trees and forbs through changing soil properties

Abstract

Various scarification treatments produce the different regeneration potentials for trees and forbs through changing soil propertiesSoil scarification removed surface layers including nutrients and buried seeds.The purpose of this study was to evaluate the success of alternative practices which intentionally leave the surface soil (screening and replacing) along with the standard scarification. We focused on soil properties, the density of buried seeds, the invasion of competitive vegetation, and the regeneration of tree species.There were significant differences in soil properties among the treatments. Soils that were treated with the replacing treatment had the highest water contents from the surface layer to the deep layer in the lower slope in particular. On the other hand, there were higher densities of tall forb germinated from rhizomes, which are likely to shade tree species, with the replacing particularly in the lower slope locations. The residual buried seed densities in the soil were estimated to be significantly higher in the screening than the replacing. Phellodendron amurense, producing seed bank and having dry tolerance, exhibited the greatest seedling density with the screening. However, there was no significant difference between screening and replacing in Betula species which has higher water demands. In conclusion, it is important that screening and replacing should be used properly according to the site condition and target tree species. The replacement had the advantage of retaining higher water content, but it is suggested that the screening is a better option when intended for regeneration from buried seeds and when many tall forb species grow alongside dwarf bamboo prior to treatment.

The 30-year impact of post-windthrow management on the forest regeneration process in northern Japan

“…Betula spp. thus occur frequently, dominating secondary forests and forming almost pure stands following scarification due to their high growth rates and reproductive abilities (Yamazaki and Yoshida 2020). A clear increase in pioneer species such as Betula spp.…”

Disentangling the direct and indirect effects of canopy and understory vegetation on the foraging habitat selection of the brown bear Ursus arctos

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Eight-year survival and growth of Sakhalin fir (Abies sachalinensis) seedlings with one weeding operation: Impact of mechanical site preparation, vegetation release, summer planting, stock type, and forwarder trail

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