Spontaneous regeneration of eucalypts from seed production areas

Abstract

Eucalypt species are widely used around the world due to their high productivity; however there are some concerns about the invasiveness capacity of eucalypts. We assessed old seed production areas of commercial eucalypt species thought of being at risk of invasion in two places in Southeastern Brazil (Anhembi: lat: 22°28 0 S; long: 48°04 0 W; and Itatinga lat: 23°02 0 S; long: 48°38 0 W). We observed differences between places and among species. The species with the higher number of plantation stands and higher demand for seeds had more regeneration. Regeneration was recorded in only a few plots and trees and seedlings were found very close to the eucalypt stand, in sites where waste from seed harvesting is dumped. For spontaneous regeneration of eucalypts to occur there is a need for favorable environmental conditions. Such conditions may be created by human activities or natural events which suppress competition from vegetation.

Natural regeneration of Pinus spp. around seed production areas and orchards

“…regenerants were found in all areas (open areas, as well as eucalyptus and native vegetation-covered areas), the regeneration density in each area corroborates the invasiveness theories regarding both species and environment. In the Anhembi and Itatinga stations, the results of similar observation work regarding eucalypts regenerants indicate that the exposed soil and the absence of predation by ants are fundamental for the successful establishment of sprouts (Silva et al 2016;Miolaro et al 2017).…”

“…These species were introduced several times in the country while many introduced populations were maintained as Seeds Production Area (SPA) and Seed Sedlings Orchards (SSO) in experimental stations to serve as seed sources for breeding programs and even commercial planting. Thus, the fact that several species may be found in the same environmental conditions allows studying the regeneration of several species in the same place, as performed for eucalypts (Miolaro et al 2017).…”