C2a: Technical innovations in forest regeneration and restoration 15:30 - 17:30 Wednesday, 2nd October, 2019 Venue R15 - WING 2 Congress Theme C. Forests and Forest Products for a Greener Future Presentation Types Oral Chair Douglass Prof, Magnus Prof

Forest regeneration and restoration have advanced considerably in the past decades due to scientific and technical innovations, Many of these advances have now been put into practice, helping to improve efficiency and productivity of operations. Some recent examples include the ability to trace nutrient and carbohydrate dynamics in , evaluation of chemical defenses and relationships between allocations to growth or defense compounds, root scanning, genotyping, and production of larger, more stress tolerant nursery stocktypes. In the future it is likely that current technologies such as infrared leaf spectroscopy, whole plant phenotyping, and use of UAV’s (I.e., drones) will open new doors to further improve silvicultural operations. This session will review the importance of some past innovations as well as look toward the future by highlighting some up and coming technologies. Because reforestation and restoration have become more crucial than ever, we believe that communiting these recent advances will help to move the field forward at a crucial time.

15:30 - 15:45

C2a Slash and burn agriculture as silvicultural treatment to regenerate macrophylla King

Patricia Negreros-Castillo1, Imelda Martínez-Salazar2, Claudia Alvarez Aquino3, Angélica Navarro Martínez4, Carl W Mize5 1Academia Nacional de Ciencias Forestales, Ciudad de México, Mexico. 2Investigador Independiente, Chetumal, Mexico. 3Universidad Veracruzana, Xalapa, Mexico. 4Colegio de la Frontera Sur, Chetumal, Mexico. 5Iowa State University, Ames, USA

Abstract

Swietenia macrophylla King ()is the most important tree species commercially in tropical America. It is so important that it could be considered a ‘financial’ keystone species because its absence increases the likelihood of conversion of a forest to another, more profitable land use. Slash and Burn Agriculture (SBA) has been used in the Maya region of the Yucatan peninsula, Mexico for more than 3,000 years, and it is the most spatially distributed disturbance in the region. Abandoned SBA fields seem to create suitable regeneration conditions for mahogany; in fact, mahogany populations in the Yucatan Peninsula exhibit strong spatial correlations with abandoned SBA fields. This research reports on direct seeding of mahogany in three slash and burn fields in Betania, Quintana Roo, Mexico during the last cropping year. In each field 121 planting sites were located in a 0.25 ha plot, and five seeds were sown at each planting site. Soil color and shading of each planting site were noted. Height, diameter and indications of damage by Hypsipyla grandellaof all sprouted seeds were recorded at 2, 11, 23, 38, 45, and 58 months after sowing. Five years later 63% of seedlings had died, leaving 7.4% of the planting sites occupied by a seedling. Sseedling height varied from 0.3 to 8 m after 58 months. Remarkably, none of 212 seedlings showed indications of damage by H. grandella. 15:45 - 16:00

C2a From past to future: Approaches to protect seeded acorns against consumption by granivorous rodents

Adrian Villalobos, Mattias Engman, Magnus Löf Swedish University of Agricultural Sciences, Alnarp, Sweden

Abstract

As one of the oldest methods for forest restoration, direct seeding has the potential to improve the cost- efficiency of restoration programs around Europe. However, acorn consumption by granivorous rodents such as the bank vole (Myodes glareolus) and the mouse (Apodemus sylvaticus) is one of the major drawbacks for the implementation of this low-cost method. Through the years several techniques have been developed in order to protect acorns from consumption. These techniques are classified into chemical, ecological, physical and site preparation approaches. The goal of these methods is to reduce the consumption of acorns, without impairing germination and seedling performance. But at the same time operation costs may increase and therefore reduce the benefits of direct seeding when compared to planting. Therefore, here we present the advantages and disadvantages of the different methods developed for acorn protection. We show the results of our current state of the art field and laboratory projects using volatile organic compounds from feces, urine or fur of rodent predators such as the stoat (Mustela erminea), American mink (Neovision vision), and the red fox (Vulpes vulpes) to deter acorn consumption from rodents. Additionally we used acorn based volatile compounds to camouflage seeded acorns. Finally, we aim to review the best available methods and the potential upcoming technologies for acorn protection in direct seeding. 16:00 - 16:15

C2a Subirrigation Effects on Seedling Growth, Root Morphology, and Media Chemistry

Fangfang Wan1, Amy Ross-Davis2, Wenhui Shi3, Christopher Weston4, Xiehai Song1, Xiaochao Chang1, Anthony Davis2, Yong Liu1, Fei Teng1 1Beijing Forestry University, Beijing, China. 2Oregon State University, Corvallis, USA. 3Zhejiang A&F University, Zhejiang, China. 4the University of Melbourne, Creswick, Australia

Abstract

Subirrigation (SI) is regarded as an environmentally-responsible method of delivering water and fertilizer to nursery-grown plants. But a potential higher salt concentration in the upper layers of growing media under SI may inhibit root growth and result in decreased plant quality, few studies have focused on how root morphology is altered by SI. This study assessed the growth response of larch seedlings when subjected to three rates of fertilization and grown using SI or overhead irrigation (OI) for one nursery season. Associated changes between rhizosphere electrical conductivity (EC) and root morphology of different root size classes were analyzed. Results show that (1) SI and OI seedlingshadsimilar height, root-collar diameter, and root volume. However, (2) compared to OI-seedlings, SI-seedlings had less root mass, length, and surface area but greater average root diameter (ARD). (3) Morphological differences were evident primarily in root diameter size classes I – III (D ≤ 1.0 mm). (4) Fertilizer rate influenced root length and surface area up to 130 days after sowing. (5) As the growing season progressed, SI-media had significantly higher EC compared to OI-media and EC increased with increasing fertilizer rate under SI but not under OI. These results indicate that SI can produce larch seedlings of similar height and root collar diameter (RCD) compared to OI, but root systems are smaller overall with fewer small-diameter roots, which may be related to high EC levels in SI-media. Therefore, the EC in the media should be monitored and adjusted by reducing fertilizer rates under SI. 16:15 - 16:30

C2a Interactive Effects of Seedling Stock Size and Vegetation Management Treatments on Douglas- Plantation Productivity After 10 Growing Seasons

Maxwell Wightman, Carlos Gonzalez-Benecke, Eric Dinger Oregon State University, Corvallis , USA

Abstract

Forest vegetation management (FVM) treatments and seedling stock type selection are important considerations in any reforestation project. The growth and survival of Douglas-fir seedlings has been shown to benefit from FVM, but the interactive effects of stock size and FVM are less well understood. This study tested the combined effects of three FVM regimes and three containerized stock sizes on Douglas-fir growth over ten years. Stock types included stryo-8, stryo-15, and styro-60 seedlings creating large differences in seedling size at the time of planting. FVM treatments included a no action control, a pre-planting herbicide treatment followed by a spring release during the first growing season, and a pre-planting herbicide treatment followed by a spring release during the first and second growing seasons. Plots that received an herbicide application had lower competing vegetation cover and higher stand volume than the no action control after ten growing seasons. The herbicide treatments applied in this study also had a long-term effect of the cover of shrubs, especially Gaultheria shallon, and shrub cover was well correlated with stand growth. Styro-60 seedlings were also larger than styro-8 seedlings after ten growing seasons but did not differ from the styro-15 seedlings. At age 10 years, the only significant stock type by FVM interactive effect was the styro-60 seedlings growing under the no action control treatment having a higher mortality rate than all other treatment combinations. 16:30 - 16:45

C2a Sistema radicular pivotante pré plantio - como parâmetro de qualidade das mudas de espécies florestais

Osmar José de Aguiar, Jaqueline Sousa Almeida Universidade do Estado do Pará, Belém, Brazil

Abstract

Apesar das altas produtividades e competitividades das florestas plantadas no Brasil, problemas fisiológicos e de fitossanidades ocorrem com frequência na região Norte. Como forma de justificar esses problemas, levantou-se a seguinte hipótese: “Mudas florestais com meristema apical radicular danificado, serão mais susceptíveis ao estresse, principalmente, nos períodos de déficit hídrico”. Sabendo-se que, com a retirada dessas células, a raiz pivotante se atrofia, e a eficiência na busca de umidade no solo, torna-se reduzida, como consequência a baixa resistência natural, aumentando a susceptibilidade à pragas e doenças. Na avaliação do desenvolvimento comparativo da parte aérea com a raiz, das mudas de ivorensis A. Chev., e Genipa americana L., semeadas em sacos plásticos de 17cm x 27cm, no viveiro em São Francisco do Pará. Selecionou- se mudas com 5 cm, 10 cm e 15 cm de altura da parte aérea, com dez repetições cada. Foi observado uma correlação direta, entre o comprimento da parte aérea e raiz, quando a parte aérea atinge altura de 10 cm, a raiz atinge o fundo do saco, o que induzirá ao enovelamento da pivotante ou se ultrapassar, será danificada, na remoção do saco no canteiro. Deste modo, parâmetros de qualidades como: idade, parte aérea e a relação da sua massa seca com a da radicular, podem não serem suficientes para garantir o bom desenvolvimento das mudas nos plantios. Espera-se que no final dessa pesquisa, poder desenvolver um novo sistema de produção de muda, onde a integridade das raízes pivotantes seja considerado como parâmetro de qualidade. 16:45 - 17:00

C2a Detecting seedling physiology with a Near Infrared (NIR) Consumer digital camera

Francesca Giannetti, Sabrina Raddi, Sofia Martini, Alberto Maltoni, Andrea Tani, Gherardo Chirici, Barbara Mariotti Università di Firenze, Firenze, Italy

Abstract

The development of new methods to monitor plantation physiological status is a key point to strengthen the success of forest restoration projects in a climate change context. An innovative forefront role can be played by NIR Consumer digital cameras. This technology, considered by remote-sensing communities as a cost- effective forest monitoring method over large area, can provide highly detailed data also at single plant scale. Our study aimed to test the possibility of monitoring seedlings physiology by NIR camera images (i.e. CANON S110 NIR) and their derived vegetation indices with the leaf physiological measurements by spectrometer and fluorimeter (i.e. USB-2000 Ocean Optics and PAM-2000 Walz). The final objective was to evaluate if in future NIR camera can be a reliable to assess seedling physiology both in nursery and after transplanting. In 2018, two parallel experiments were carried out on seedlings coming from the same nursery stock grown in 2017 in Central Italy: six different combinations of three Quercus species grown in two substrates (peat and coconut fiber), and three different fertilizations (nursery standard, P-enriched, K-enriched). We concurrently monitored seedlings both during a water test under controlled conditions (three water regimes) at leaf and plant scale, and at plantation scale by an Unmanned Aerial Vehicle. The first results revealed a good correlation between spectrometer and NIR camera bands, with the advantage for NIR camera of collecting information on images that cover one or several entire leaves and, potentially, the whole plant in comparison with the on-time punctual data obtained by spectrometer. 17:00 - 17:15

C2a RESTAURANDO FLORESTAS NATIVAS NO BRASIL COM SEMEADURA DIRETA

Eduardo Campos Filho1, Guilherme Carmo2, Heber Alves2, Lara Costa2, Juliano Nascimento3, Rodrigo Junqueira4 1ISA - Instituto Socioambiental, São Paulo, Brazil. 2ISA - Instituto Socioambiental, Canarana, Brazil. 3ISA - Instituto Socioambiental, Eldorado, Brazil. 4ISA - Instituto Socioambiental, Brasília, Brazil

Abstract

A semeadura direta de muvuca de sementes tem sido utilizada e aperfeiçoada desde 2006 no Xingu, pelo ISA - Instituto Socioambiental e parceiros, onde tem sido considerada uma forma ágil, barata e eficaz de restauração florestal, com aspectos que dialogam com as habilidades dos proprietários rurais e, consequentemente, com a restauração em larga escala: flexibilidade técnica para a implantação, desde a mecanização até o plantio manual, melhor desenvolvimento de raízes e resistência a secas, densidade dos grupos ecológicos e distribuição espacial mais semelhante a capoeiras naturais e rápida cobertura do solo. O método é recente no Brasil, embora seja utilizado há décadas em outros países. Serão apresentadas técnicas e resultados de semeaduras diretas de muvuca monitoradas em MT, SP, BA e ES nos biomas Amazônia, Cerrado e Mata Atlântica. Os cuidados desde a escolha de espécies, coleta, beneficiamento e armazenamento das sementes, preparo do solo, plantio, monitoramento e manejo, incluindo uso ou não de herbicidas serão abordados. Serão discutidas questões sobre a cadeia produtiva para a semeadura direta, custos, resultados ecológicos e sociais, gargalos e principais lacunas para o aprimoramento do método. A estruturação de uma cadeia regional de produção de sementes, que seja capaz de atender à demanda da semeadura direta e de produzir os benefícios sociais, econômicos e de biodiversidade almejados pelos diferentes atores envolvidos, depende da governança sobre a produção de sementes e sobre a demanda por sementes nativas decorrentes das áreas a restaurar a cada ano. 17:15 - 17:30

C2a The presence of exotic tree species may not necessarily limit natural regeneration in tropical forest restoration

Nino Amazonas1, Tiago Barreto1, Paulo Sérgio Sampaio de Oliveira2 1Fundação Espaço ECO, São Bernardo do Campo, Brazil. 2REVERDE, Guaratinguetá, Brazil

Abstract

When forest restoration started spreading in Brazil, species diversity was not a serious concern, nor was the exclusive use of native species. In that context, Syzygium jambolanum (Lam.) DC. was widely planted. Nowadays, eliminating exotic trees is an important component of management plans as it is a common belief that natural regeneration is limited by allelopathic effects or by characteristics of the leaf litter of exotic species. However, this limitation must be evaluated case by case. We are evaluating natural regeneration in a restoration project located in Guaratinguetá, São Paulo, in the Atlantic Forest of Brazil to test the hypothesis that S. jambolanum is hindering natural regeneration. We measured sapling density under the canopy of S. jambolanum and under native trees and used a general linear model to test if density was related to the canopy species, leaf litter thickness or forest age (older, intermediate and younger patches). In this first assessment, we found that sapling density was not influenced significantly by canopy species nor litter thickness. However, forest age was an important factor related to sapling density, with higher sapling density the older the patches, regardless of other factors tested. From our initial results, we suggest that management plans should be designed considering careful evaluations of the real impacts of tree species. In some cases, eliminating exotic species may be a disadvantage and other management measures, such as enrichment plantings, should be preferred instead. Moreover, we believe native species will gradually replace exotic trees when these start senescing.