Elise Buisson
email: elise.buisson@univ-avignon.fr

Swanni T Alvarado
email: swanni_ta@yahoo.es

Soizig Le Stradic
email: soizig.lestradic@gmail.com

Patricia C Leonor

Morellato
email: pmorella@rc.unesp.br

Plant phenological research enhances ecological restoration Authors

Keywords: exotic species, genetic provenance, germination, restoration management, monitoring, phenology, seed harvest, seed production, seed mixes, species interactions

While phenology data (the timing of recurring biological events) has been used to explain and predict patterns related to global change, and to address applied environmental issues, it has not been clearly identified as pertinent for restoration. This opinion paper thus aims to raise awareness of the potential of phenology to enhance the quality of restoration projects and ecological restoration theory. We based our analysis on a systematic literature survey carried out in February 2014, searching the words "phenology" or "phenological" in books dealing with restoration, the term "phenolog*" in the journal Restoration Ecology, and the terms "restoration" and "phenolog*" in the database Web of Science until February 2014. We finally selected 149 studies relevant to our goals, and first classified them according to the context in which phenology was addressed. We then analyzed them within the framework of the five key steps of restoration projects: 1) the reference ecosystem, 2) biotic resources, 3) restoration methods, 4) monitoring, and 5) adaptive management. The literature survey showed that phenological information improved decision-making in the few restoration projects in which it was incorporated. We thus advocate taking phenological data into account at all stages of restoration when appropriate: from the acquisition of baseline data on the reference ecosystem to treatment design, and from restoration action planning and timing to monitoring. Phenological data should at minimum be collected for sown, keystone, dominant and/or rare species to improve restoration quality. Phenology studies and monitoring should be promoted in future restoration guidelines.

Introduction

Phenology is the study of the timing of recurring biological events, the causes of their occurrence with regard to biotic and abiotic forces, and interactions among phases of the same or different species [START_REF] Lieth | Phenology and Seasonality Modeling[END_REF][START_REF] Schwartz | Phenology: An Integrative Environmental Science[END_REF]. Phenological changes are easily monitored and have marked effects on health, biodiversity, nutrient cycling, forestry, agriculture and the economy [START_REF] Schwartz | Phenology: An Integrative Environmental Science[END_REF][START_REF] Morellato | Linking plant phenology to conservation biology[END_REF]). The study of phenology has gained importance over the past 20 years with the increased concern over climate change (Chambers et al. 2013). Phenology data is increasingly being used to explain and predict various patterns related to other forms of global change [START_REF] Schwartz | Phenology: An Integrative Environmental Science[END_REF], as well as to address applied environmental issues [START_REF] Morisette | Tracking the rhythm of the seasons in the face of global change: phenological research in the 21st century[END_REF][START_REF] Morellato | Linking plant phenology to conservation biology[END_REF]. While phenology is an interdisciplinary science that has contributed to many disciplines, so far it has not been clearly identified as pertinent for restoration. [START_REF] Morellato | Linking plant phenology to conservation biology[END_REF] have recently highlighted the importance of phenology for conservation science and management, pointing out the likely implications of phenology for restoration ecology, particularly for seed collection. However, their paper does not explore the various situations in which phenological research can potentially improve the quality of ecological restoration projects. We thus provide here a discussion of how phenological research should be incorporated in ecological restoration. We base this opinion paper on a literature survey in which we examined 149 books, book chapters, or papers relating phenology and restoration (Supporting Information, Appendix S1 and S2, Figure S1, Table S1, S2, S3). Most studies dealt with plant phenology and restoration, likely because plant material is the most important biotic resource used to restore ecosystems. We examine these studies within the framework of the five key steps of restoration projects (Figure 1): 1) establish the reference ecosystem, 2) identify biotic resource needs and sources, and obtain them, 3) implement selected restoration methods and strategies, 4) set up permanent monitoring, and 5) implement adaptive management procedures [START_REF] Clewell | Guidelines for developing and managing ecological restoration projects[END_REF]). We lastly discuss how restoration ecology can also contribute to phenological research by providing new insights that will help explore innovative questions on drivers and patterns in phenology.

How can phenology improve baseline data on reference ecosystems and biotic resources for restoration?

Ecological restoration often requires modification of the physical environment and vegetation manipulation [START_REF] Whitenant | Repairing Damaged Wildlands: a Process-Oriented, Landscape-Scale Approach[END_REF], with the fauna frequently expected to colonize by itself. Although more attention is paid to the animal component nowadays (e.g. taking species interactions into account, or avoiding disturbance to the fauna), the biotic resources used in restoration projects often remain plant material. Despite the fact that animal phenology can be a key factor in improving pollination, seed dispersion and invasive species control [START_REF] Morellato | Linking plant phenology to conservation biology[END_REF], and that animals' presence is likely an indicator of restoration success, our review showed that less than 10% of studies refer to animal phenology (and around 15% look at interactions of plants with animals, mainly pollinators or herbivores). The following sections therefore focus more on plant communities and specify the reasons why it is important to collect detailed information on the phenology of plant communities of the reference ecosystem and of the restored site (Figure 1).

Gathering local plant material

Local biotic resources are best for carrying out restoration (Bucharova et al. 2016) and can be obtained by gathering local seeds (e.g. [START_REF] Kiehl | Species introduction in restoration projects -Evaluation of different techniques for the establishment of semi-natural grasslands in Central and Northwestern Europe[END_REF]. It is obviously necessary to know the phenology of the reference ecosystem plant community in order to adequately plan seed harvest(s). A phenological calendar of the reference plant community or of the target species within the reference plant community was prepared in a number of the reviewed papers and books on various ecosystems (e.g. tallgrass prairies of the USA; [START_REF] Packard | The Tallgrass Restoration Handbook: For Prairies[END_REF]. While empirical knowledge of when the majority of fruits are mature is often available in temperate ecosystems, such information is much less common in the tropics or in aseasonal communities. Using phenological information, a fruiting calendar can be created to select seed species, quality, quantity, etc. and to plan effective harvesting. Data on phenology can also help to explain post-restoration differences in species richness between the reference and the restored sites relative to the timing of seed harvests [START_REF] Kiehl | Evaluation of initial restoration measures during the restoration of calcareous grasslands on former arable fields[END_REF].

Optimizing seed production

Prior to seed harvest, management of reference sites can be adapted to optimize seed production, which requires a good understanding of specific management effects on plant phenology. Some of the papers we reviewed investigated fruit production under different management strategies, such as increased soil fertility and decreased toxicity. For example, González [START_REF] Melo | Diferencias en la producción de frutos del roble Quercus humboldtii Bonpl. en dos bosques andinos de la cordillera oriental colombiana[END_REF] show that the Andean oak (Quercus humboldtii) yields more fruit on soils with a high content of phosphorus and potassium and low soil aluminum. They thus suggest managing the soil to optimize fruit production. Other articles address flowering, fruit production and seed set in relation to disturbance intensity or frequency (fire, grazing, mowing, etc.). [START_REF] Meyer | Fire season and mulch reduction in a California grassland: a comparison of restoration strategies[END_REF] demonstrate that fire season is a significant factor in grassland restoration, and that the impact of different fire seasons on restoration success is determined by plant phenology patterns and seasonspecific fire intensities. [START_REF] Wrobleski | Initial effects of prescribed fire on morphology, abundance, and phenology of forbs in big sagebrush communities in southeastern Oregon[END_REF] indicate that prescribed fire can increase native flower abundances, providing more seeds to be collected for restoration projects. When appropriate, we thus suggest the use of prescribed fires as a management tool to improve fruit production (Figure 2, and Supporting Information, Appendix S2 Figure S2).

Producing local plant material

Gathering wild local plant material is not always an option for restoration: i) because the reference ecosystem may either be protected, ruling out seed harvest, or no longer exist, ii) because the area to be restored may be too big compared to the areas of remaining reference ecosystem, or iii) because it is not very efficient compared to the commercial production of seeds of local provenances. The latter technique is often used, and here too phenology studies can help solve problems of propagation for species yielding low quantities of viable seeds (e.g. Spartina alterniflora, saltmarsh cordgrass; [START_REF] Fang | Influence of flowering phenology on seed production in smooth cordgrass (Spartina alterniflora Loisel.)[END_REF]). The proportion of each species in commercial seed mixes is determined using various functional types, and early phenology can be a useful criterion to take into account (Carter & Blair 2012). During propagation, the timing of germination, flowering and fruiting of wild plants can change over several generations, because phenological traits are under strong selection. Thus, the plant material might become phenologically ill-adapted [START_REF] Schröder | From nursery into nature: A study on performance of cultivated varieties of native plants used in re-vegetation, their wild relatives and evolving wild × cultivar hybrids[END_REF]. Additionally, once on the restoration sites, cultivated plants can be naturally selected, thus favoring a particular trait, e.g., earlier flowering phenology [START_REF] Kulpa | Strong natural selection during plant restoration favors an unexpected suite of plant traits[END_REF]. Considering these phenological issues ahead of seeding and out-planting, and even ahead of production, can reveal the importance of using locally adapted plant material [START_REF] Kiehl | Guidelines for Native Seed Production and Grassland Restoration[END_REF] to enhance plant establishment and to increase functional diversity and ecosystem functioning, thus improving restoration.

Conserving genetic diversity and local adaptations

Phenological studies can help address the issues related to seed collection by: i) preventing the reduction of genetic diversity of local ecotypes [START_REF] Holmstrom | Dune restoration introduces genetically distinct American beachgrass, Ammophila breviligulata, into a threatened local population[END_REF], and ii) ensuring that seeds are phenotypically suited to their home conditions [START_REF] Miller | Can an ecoregion serve as a seed transfer zone? Evidence from a common garden study with five native species[END_REF]. Phenological studies that examine whether flowering times overlap can determine whether native but non-local genotypes introduced on restored sites have the potential to cross-pollinate and to hybridize with surrounding remaining natural genotypes [START_REF] Holmstrom | Dune restoration introduces genetically distinct American beachgrass, Ammophila breviligulata, into a threatened local population[END_REF]. Indeed, some introduced genotypes can have advantages over local plants in vegetative and/or sexual reproduction, and can out-compete native genotypes or colonize outside of restoration sites [START_REF] Holmstrom | Dune restoration introduces genetically distinct American beachgrass, Ammophila breviligulata, into a threatened local population[END_REF]. Detection of this advantage is particularly important in the case of small and isolated populations [START_REF] Holmstrom | Dune restoration introduces genetically distinct American beachgrass, Ammophila breviligulata, into a threatened local population[END_REF]. Information on the dates of budbreak, germination, flowering and/or seed set and on flower abundance [START_REF] Miller | Can an ecoregion serve as a seed transfer zone? Evidence from a common garden study with five native species[END_REF]) have proven essential to guarantee that using locally adapted seed sources preserves adequate phenological cycles and to ensure the reproductive success of introduced species.

Taking species interactions and ecosystem services into account

Because leaf, flower and fruit phenologies link plants to herbivores, pollinators, frugivores and seed dispersers, studying plant phenology involves taking into account resource availability and interaction networks, encompassing ecosystem and landscape complexity [START_REF] Hagen | Biodiversity, species interactions and ecological networks in a fragmented world[END_REF]). In the context of food webs, phenology helps detect when and in which conditions a particular food resource is available, and can pin-point habitat restoration needs for the species feeding on this particular resource (e.g. [START_REF] Wrobleski | Initial effects of prescribed fire on morphology, abundance, and phenology of forbs in big sagebrush communities in southeastern Oregon[END_REF]. When restoring/reintroducing a population, some knowledge of species phenology (food, competitors, etc.) regarding this restored population is particularly important. As an example, phenology can provide restorationists with a method that selects plant species based on the timing of fruiting. This will enable them to attract potential seed dispersers and provide fruits all year long [START_REF] Garcia | Flower and fruit availability along a forest restoration gradient[END_REF], to match fruit availability with frugivore requirements over time and space [START_REF] Gosper | Approaches to selecting native plant replacements for fleshyfruited invasive species[END_REF] and to connect the landscape through resources for both pollinators and seed dispersers [START_REF] Hagen | Biodiversity, species interactions and ecological networks in a fragmented world[END_REF][START_REF] Morellato | Linking plant phenology to conservation biology[END_REF]. Phenology thus facilitates the restoration of ecosystem services, such as key food and other non-timber resources (e.g. fruits, leaves, medicinal plants), and can help sustain human population needs [START_REF] Garibaldi | Wild pollinators enhance fruit set of crops regardless of honey bee abundance[END_REF] (see another example in Supporting Information, Appendix S2 Figure S2). Plant phenology on restoration sites should be combined with the phenology of pollinators, seed dispersers or migrating species among others [START_REF] Schellhorn | Time will tell: resource continuity bolsters ecosystem services[END_REF]. This would make it possible to encompass not only most scales, from local communities to ecosystems, focusing on connectivity across the landscape, but also time (e.g. asynchrony on flowering or fruiting time between restored and reference sites may break the temporal connectivity between vegetation patches).

How can phenology enhance restoration treatments and management?

Optimizing the timing of restoration treatments Restoration treatments also have to be finely tuned and timed to maximize target species establishment and minimize the harm done to healthy populations of plants or animals remaining in the degraded site to be restored. To achieve this, the phenology of different groups of species (not just plants) needs to be known. Phenological information can be useful to avoid disturbance (e.g. destruction of bird nesting) during the restoration process or to maximize plant establishment from the seed bank. A calendar taking into account the phenology of both animals and plants is often the basis of restoration planning [START_REF] Jaunatre | Note méthodologique : Exemple de restauration de la plaine de la Crau: l'écologie de la restauration face à la restauration écologique[END_REF], although it is rarely clearly stated as phenological information in the papers reviewed.

Dealing with exotic species

In the case of restoration involving removal or control of exotic species, appropriate timing of treatment application requires knowledge of both native and exotic species phenology. Exotics can leaf or bloom during times when natives do not (thus filling a vacant niche), or can flower or germinate earlier than natives (thus benefiting from a priority effect; Wolkovich & Cleland 2011; Figure 1). Restoration treatments should therefore be applied when exotics are vulnerable but natives are not (e.g., fire, grazing, herbicide; [START_REF] Marushia | Phenology as a basis for management of exotic annual plants in desert invasions[END_REF][START_REF] Ruckman | Effects of phenology at burn time on post-fire recovery in an invasive C4 grass[END_REF]. Phenology studies can also facilitate accurate identification of the risks from non-native species. For example, precise identification of natives and exotics with matching phenology may pin-point species that could then hybridize and induce a loss of both genetic diversity and locally adapted populations [START_REF] Vilà | Conservation implications of invasion by plant hybridization[END_REF]. Species with matching phenologies can also be in competition for pollinators and dispersers, thereby altering fruit quantity, quality and dispersal, and thus community structure and ecosystem functioning [START_REF] Vilà | Conservation implications of invasion by plant hybridization[END_REF][START_REF] Morellato | Linking plant phenology to conservation biology[END_REF].

Recovering ecosystem functions

Because of the constant feedback occurring between the abiotic environment and the biota [START_REF] Temperton | Assembly Rules and Restoration Ecology: Bridging the Gap Between Theory and Practice[END_REF]), precise information on the phenology of species can allow restorationists to re-introduce species that contribute to the recovery of some ecosystem functions. Native species with spring phenologies can reduce early-season nutrient run-off (Brudvig 2010). Fire can increase flower abundance and extend phenology, which can have a positive effect on bird species foraging activities [START_REF] Wrobleski | Initial effects of prescribed fire on morphology, abundance, and phenology of forbs in big sagebrush communities in southeastern Oregon[END_REF] (Figure 2). Therefore, taking phenology into account when planning the timing and intensity of restoration treatments will enhance restoration of ecosystem regulating functions (e.g. nutrient conservation) or supporting functions (e.g. food resources). Moreover, enriching plant communities invaded by exotic species with selected native species of matching phenologies and competitive characteristics can help them out-compete undesired species [START_REF] Simmons | Bullying the bullies: the selective control of an exotic, invasive annual (Rapistrum rugosum) by oversowing with a competitive native species (Gaillardia pulchella)[END_REF]. Finally, phenology is an essential parameter to evaluate restoration treatments and post-restoration management (e.g., Carter & Blair 2012). This should encourage restorationists: i) to focus on ecosystem functions and species composition not only as goals but also as tools to reach restoration objectives [START_REF] Shackelford | Primed for change: developing ecological restoration for the 21st century[END_REF]; and ii) to incorporate phenology in restoration planning (Figure 1).

How can phenology improve restoration monitoring?

Monitoring sites before and after restoration is essential in order to assess the success of restoration projects in achieving pre-defined goals and to improve future restoration practices [START_REF] Holl | Monitoring and appraisal[END_REF]. It is also one of the main aspects that need improvement in restoration projects [START_REF] Palmer | Standards for ecologically successful river restoration[END_REF]. Parameters monitored for restoration depend on the objectives of the project and can be very diverse [START_REF] Kollmann | Integrating ecosystem functions into restoration ecology -recent advances and future directions[END_REF], ranging from ecosystem functioning to the presence of target species such as plankton (Anneville et al. 2007) or aquatic plants [START_REF] Cho | Seasonal growth and reproduction of Ruppia maritima L. s.l. in Lake Pontchartrain, Louisiana, USA[END_REF], reference grassland species [START_REF] Kiehl | Evaluation of initial restoration measures during the restoration of calcareous grasslands on former arable fields[END_REF], forb species [START_REF] Wrobleski | Initial effects of prescribed fire on morphology, abundance, and phenology of forbs in big sagebrush communities in southeastern Oregon[END_REF], trees [START_REF] Garcia | Flower and fruit availability along a forest restoration gradient[END_REF], larval amphibians and predatory macroinvertebrate families [START_REF] Curtis | Assessing detection probabilities of larval amphibians and macroinvertebrates in isolated ponds[END_REF], and seabirds [START_REF] Hall | Comparison of common tern reproductive performance at four restored colonies along the Maine coast, 1991-2002[END_REF]). The main phenological monitoring techniques are based on seasonal in-the-field species monitoring, but recent studies have used remote sensing to monitor restored ecosystems: [START_REF] Dufour | Monitoring restored riparian vegetation: how can recent developments in remote sensing sciences help?[END_REF] applied Light Detection And Ranging (LiDAR), radar, and Unmanned Aerial Vehicle (UAV), and van Leeuwen (2008) analyzed a Normalized Difference Vegetation Index (NDVI) from satellite imagery. Repeated photographs taken by digital cameras can also be a cheap and efficient way to monitor species and community changes over time (see [START_REF] Richardson | Near-surface remote sensing of spatial and temporal variation in canopy phenology[END_REF]Alberton et al. 2014), before or after restoration.

What can phenology research learn from restoration?

The different phenological studies included in restoration projects were carried out with various restoration improvement aims: identify the best plan monitoring time [START_REF] Cho | Seasonal growth and reproduction of Ruppia maritima L. s.l. in Lake Pontchartrain, Louisiana, USA[END_REF], define the right timing for application of restoration treatments [START_REF] Cho | Seasonal growth and reproduction of Ruppia maritima L. s.l. in Lake Pontchartrain, Louisiana, USA[END_REF], study the effects of restoration treatments on interactions [START_REF] Wrobleski | Initial effects of prescribed fire on morphology, abundance, and phenology of forbs in big sagebrush communities in southeastern Oregon[END_REF]Anneville et al. 2007;[START_REF] Garcia | Flower and fruit availability along a forest restoration gradient[END_REF], provide information on the effectiveness of restoration treatments [START_REF] Kiehl | Evaluation of initial restoration measures during the restoration of calcareous grasslands on former arable fields[END_REF]) and plan management [START_REF] Curtis | Assessing detection probabilities of larval amphibians and macroinvertebrates in isolated ponds[END_REF]. However, well-established monitoring in restoration ecology can also feed long-term phenological databases on reference ecosystems, target, dominant or rare species, providing many new insights into phenological patterns (Table 1). A wide range of research questions remains to be tackled (Table 1). Can the phenology of native species or invasive species determine their co-occurrence or their ability to colonize and become established in the restored area? Do we observe variations in phenological patterns in plant species/communities that could be related to the modification of edaphic conditions? Can we re-establish interactions or ecosystem services using non-local plants or using local plants according to their phenology? Do some restoration treatments affect plant phenology, and how do these treatments affect plantanimal interactions? As restoration is commonly seen as an acid test of theoretical ecology (Bradshaw 1990), we suggest that restoration can enhance the understanding of phenological patterns within the framework of land-use change.

Conclusion

This paper aimed to increase awareness of the potential of phenological research to improve the quality of ecological restoration projects. While our literature survey demonstrates this potential, we find that phenology is currently mainly applied to assessing biotic resources. Thus, we conclude that phenology remains widely underexplored within restoration projects. Yet phenology has a huge capacity to improve the quality of ecological restoration, and many more applications to restoration remain to be explored. In order to better understand the role that phenological research can play in restoration, restorationists and land managers should: 1) acknowledge that they are using phenological data, (phenological data is often used empirically without being mentioned in technical reports and articles), and 2) work at incorporating phenology into all stages of restoration projects, when appropriate. Restoration guidelines should promote at least basic, rapidly-performed phenology monitoring tasks, such as regular monitoring of sown, keystone, dominant or rare species on restored sites. The Society for Ecological Restoration International Science & Policy Working Groups should promote the use of phenology in restoration projects in appropriate documents, such as future restoration guidelines (e.g. [START_REF] Shackelford | Primed for change: developing ecological restoration for the 21st century[END_REF].

Table 1. Research questions and items that can be tackled on phenology (right hand side) within the context of restoration projects. We organized them according to the five major key steps of restoration projects [START_REF] Clewell | Guidelines for developing and managing ecological restoration projects[END_REF]; left hand side).

Key steps of restoration projects

Phenology research questions 1) Establish the reference

Phenological data collected to set up restoration projects can generate a good database useful for phenological studies at broad scales. Data can be collected both on the reference ecosystem (e.g., calendar for seed collection) and on the species that established after disturbance on the area to be restored.

 Can phenology help us to understand the occurrence of species and/or their ability to colonize and establish in degraded areas?  Do we observe changes in the phenology of species occurring in restored/degraded areas, in comparison to the phenology observed in pristine areas (phenological differences linked to different environmental conditions, such as microclimate or soil conditions?)

2) Obtain biotic resources Phenological data collected to improve seed collection, to produce seedlings and to better select species, and results of restoration projects using local and non-local plant species, can bring new insight on local phenological patterns.

 Are there advantages in using non-local vs. local plants depending on their phenology?  Are there phenological differences between invasive species and native species or between commercially produced populations and local populations on restored areas? This can, for example, bring new insight on invasive species success.

3) Implement the selected restoration methods

Phenological data collected on restored areas and on the species established after restoration. To explore particular questions on the effects of soils or succession on phenology, one can use restored areas instead of having to build specific large-scale protocols.

 Does the restoration treatment (nutrient application, mowing, fire, etc.) affect plant phenology? This should help to understand the impact of nutrient increase on plant phenology. Does mowing applied to restore plant communities modify plant phenology? How does this affect plant-animal interactions?  How do restoration actions influence plant phenology and plant-animal interactions, such as pollination and seed dispersal?  Do the control of invasive species as a treatment to restore degraded areas impact the phenology of invasive species (e.g., fruit production) and/or of native species (e.g., changes of quantity of pollinators might alter phenology or seed production of native species transplanted/translocated in degraded areas)

4) Set up permanent monitoring

Phenological surveys might be one ecosystem variable that can be used in a restoration evaluation, and phenological data collected during restoration monitoring may generate a good database and long-term data sets useful for phenological studies.

 Monitoring the restored communities should be carried out along with monitoring reference communities which serves as controls; long-term data sets can thus be collected on reference areas and contribute to answering questions such as: how is climate change influencing plant phenology in both restored and pristine areas?  With phenological data on the restored area: How does plant community phenology change along succession? Does restoring plant communities lead to the recovery of plantanimal interactions?  Assessment of the phenology of some transplanted species can improve the global understanding of such species  New techniques of phenology monitoring can be applied to ecological restoration (i.e., monitoring restored communities) and bring some feedback on these techniques as well as the plant responses over time.  Monitoring phenology of restored communities improves our understanding of the ecology of the pristine communities including the plant-animal interactions and their importance to the structure and resilience of plant and animal communities.

5) Implement adaptive management

Adaptive management on restored sites may generate data coupled with particular management regime.

 How does plant phenology change with changes in management type or regime?  How do finely timed plant-animal interactions change with restoration?  Can restored phenological patterns help re-establish interactions or ecosystem services and with what management regime? Out of the 42 books analyzed, nine did not mention either the word "phenology" or "phenological" (Figure S1). Of the 33 other books (including 627 chapters), 49 books and book chapters mentioned phenolog* at least once: 21 did so in a context that was not relevant to this study (e.g. in the context of climate change), and only 28 mentioned either "phenology" or "phenological" in a context relevant to restoration. Most of the mentions concerned "seed harvest, production and mixes" (34.5%) and "lack of knowledge" (24.1%). The other categories together totaled 41.4%: exotic species (6.9%), functions/traits (0%), genetic provenance (10.3%), germination (0%), management (10.3%), monitoring (6.9%) and species interactions (6.9%) (Table S3). We did not expect to find so many mentions of a lack of phenological knowledge that might otherwise be useful for restoration. This category is particularly well represented in book chapters, probably because it is easier to mention a flaw in a book on a particular theme or ecosystem than in articles. The "seed harvest, production and mixes" category is also well represented because many of the books were concerned with a particular ecosystem, such as Southwestern ponderosa pine forests, tallgrass prairies, dry forests in Chiapas, Mexico or floodplain forests in Europe, etc., where a lot of precise information is available (Table S3).

In Restoration Ecology (which published 1644 papers up to February 2014), 183 papers contained the term "phenolog*", 163 in a context not relevant to this study or simply related to plant survival and growth (Figure S1). Twenty papers mentioned the term "phenolog*" in a context directly related to restoration projects (1.22% of the articles published in Restoration Ecology; Table S3). They were well distributed among the nine categories (Table S3): seven papers (22.6%) discussed phenology within the context of "species interactions", five (16.1%) within the context of "genetic provenance", another five (16.1%) on "monitoring", four (12.9%) within the context of "exotic species" and four (12.9%) on "seed harvest, production and mixes". Other categories had few papers (management and functions/traits: two papers each (6.5%), and germination and lack of knowledge: one paper each (3.2%)).

The Web of Science database (8695 papers published on restoration) yielded 172 papers containing the terms "restoration" AND "phenolog*" in the topic (Figure S1). Out of those 172 papers, 71 mentioned "phenolog*" in a context which was not relevant to this study. Of the 101 papers analyzed (1.16% of the articles concerning restoration in Web of Science), the majority were published after 2004, most from 2009 onwards, yielding from 15 to 20 papers per year. The most common contexts in which the term phenology was cited were (Table S3): "seed harvest, production and mixes" (25 papers, 18.9%), "species interaction" (24 papers, 18.2%), "genetic provenance" (21 papers, 15.9%), "management" (17 papers, 12.9%) and "germination" (16 papers, 12.1%). Other categories had fewer papers (monitoring: 15 papers (11.4%), exotic species: 11 papers (8.3%), functions/traits: 3 papers (2.3%), and there was no paper on lack of knowledge.

Most of the 149 books, book chapters and papers selected dealt with plant phenology, although 20 reported data on animal phenology (insects, crustaceans, amphibians, fish, birds, lemurs). Our study is far from exhaustive, as not all the papers that deal with restoration and phenology were found in the databases. This is partly because not all authors mentioned i) the word phenology even though they actually studied some phenologically-driven patterns, or ii) the word restoration even when the study could be relevant to restoration (e.g. invasive species control or managed relocation). Nevertheless, the results of our literature survey allowed us to identify recurrent themes and to build a framework for links between phenology and restoration based on five key steps of restoration projects (Figure 1): 1) establish the reference ecosystem, 2) identify biotic resource needs and sources, and obtain them, 3) implement selected restoration methods and strategies, 4) set up permanent monitoring, and 5) implement adaptive management procedures [START_REF] Clewell | Guidelines for developing and managing ecological restoration projects[END_REF].

Literature cited for Appendix S2

Clewell AF, Rieger J, Munro J (2005) Guidelines for developing and managing ecological restoration projects. http://www.ser.org/docs/default-document-library/ser_international_guidelines.pdf.

Accessed 13 Oct 2016

Appendix S2 -Table S3 List of the 149 relevant chapters or papers selected for this study. We identified 28 book chapters, 20 articles in the journal Restoration Ecology, and 101 articles on the Web of Science (out of 404 surveyed) which studied both phenology and restoration and which were relevant to restoration according to at least one of the nine categories of application: exotic species; functions/traits; genetic provenance; germination; management; monitoring; seed harvest, production and mixes; species interactions; and lack of knowledge (Table S2)

Figure 1 .

 1 Figure 1. Conceptual framework showing where phenology can contribute to restoration. Numbers 1 to 5 are five major key steps of restoration projects[START_REF] Clewell | Guidelines for developing and managing ecological restoration projects[END_REF]. Phenological information that may be collected for restoration projects are found in boxes on the right hand side of the figure. Arrows show how specific phenological information can contribute to specific restoration steps.

Figure 2 .

 2 Figure 2. Example of the application of phenology to restoration based on a study by Wrobleski & Kauffman (2003) carried out with the following reference ecosystem: open big sagebrush (Artemisia trindentata) plant community with a rich ground-layer of forbs and grasses (Great Basin and Intermountain regions of the US Pacific Northwest). Solid lines represent the phenological information gathered in this study. Dotted lines represent either information gathered in other studies (cited in Wrobleski & Kauffman 2003) or future phenological studies that would help subsequent restoration steps.

  . Source: DB = Database, BC = book or book chapter, RE = Restoration Ecology and WS = Web of Science.

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	BC BC BC BC RE RE RE WS WS WS WS WS WS WS WS WS WS WS WS WS WS	Texas snowbells (Styrax Population and Experimental analysis of Restoration of species (Gaillardia Approaches to selecting communities in Genetic variation for Restoration of in the US Great Basin Mapping genetic Synchronous phenology conopsea s.l. Are all intertidal semi-arid system Evolution of critical day Succession and dominated grasslands Assessing detection Rangewide provenance native annual forb Effects of spreading Monitoring the effects of two Texas prairies savannah by dry forest Biological flora of the Management of genetic Comparison of common supported Technical note: early Propagating framework	1996 McDonald CB 2006 Falk DA, Richard CM, 2011 Willamns-Linera G, 2012 Blay D 2009 Gosper CR, Vivian-2011 Parsons MC, Jones TA, 2004 Riley JD, Craft IW, 2010 Johnson RC, Erickson 2011 Cruz-Neto O, Machado Jacquemyn H 2012 Friess DA, Krauss KW, 2012 Bean DW, Dalin P, 2009 Quesada M, Sanchez-2010 Curtis AE, Paton PWC Wetlands Restoring Diversity: Foundations of Perrow MR, Davy AJ Principles and Practice A Goal-Oriented D, Dudley N (eds) Restoration Ecology Restoration Ecology Restoration Ecology Botany-Botanique Biodiversity and Biological Reviews Evolutionary Forest Ecology and 2005 Mylecraine KA, Kuser Forest Ecology and 2013 Kirkham FW, Bhogal A, Grass and Forage 2008 van Leeuwen WJD Sensors 2009 Jacquemyn H, Endels Journal of Ecology 2005 Eriksson G, Pliura A, Proceedings of the Third 2004 Hall CS, Kress SW Waterbirds 2001 Doescher PS Journal of Range 2002 Blakesley D, Elliott S, Forest Ecology and
	Source DB BC BC BC BC BC BC BC BC BC BC BC BC BC BC BC BC BC BC BC BC BC BC BC BC RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS WS	Title of paper of chapter Date Authors 2012 Van Andel J, Aronson J Restoration Ecology: the Journal / Book New Frontier Prairies 1990 Kline VM, Howell EA Restoration Ecology -a Synthetic Approach to Ecological Research Jordan III WR, Gilpin ME, Aber JD (eds) Restoration, revegetation, and the importance of genetic and evolutionary perspectives 1996 Linhart YB Wild Land Shrub and Arid Land Restoration Symposium: Proceedings Roundy BA, Durant McArthur E, Hayley JS, Mann DK (eds) texana) reintroduction Strategies for Reintroduction of Endangered Plants Falk DA, Olwell M, Millar CI (eds) Exotic invasive plants 2003 Sieg CH, Phillips BG, Moser LP Ecological Restoration of Southwestern Ponderosa Pine Forests Friederici P (ed) Understory vegetation 2003 Korb JE, Springer JD Ecological Restoration of Southwestern Ponderosa Pine Forests Friederici P (ed) Stimulating natural regeneration 2005 Holz S, Placci G Forest restoration in Landscapes -Beyond planting trees Mansourian S, Vallauri D, Dudley N (eds) Obtaining and processing seeds 2005 Apfelbaum SI, Bader BJ, Faessler F, Mahler D The Tallgrass Restoration Handbook, for Prairies, Savannas and Woodlands S Packard (ed) ecological genetics in restoration ecology Montalvo AM, Knapp EE Restoration Ecology Falk DA, Palmer MA, Zedler JB Using ecological theory to manage or restore ecosystems affected by invasive plant species 2006 D'Antonio CM, Chambers JC Foundations of Restoration Ecology Falk DA, Palmer MA, Zedler JB Project planning and evaluation 2007 Clewell AF, Aronson J Ecological Restoration -Principles, Values, and Structure of an Emerging Profession 2007 Ribeiro Rodrigues R, Venâncio Martins S High Diversity Forest Restoration in Degraded Areas: Methods and Projects in Brazil Return of natural, social, and financial capital to the hole left by mining 2007 van Eeden JD, Lubke RA, Haarhoff P Restoring Natural Capital: Science, Business, and Practice Aronson J, Milton SJ, Blignaut JN (eds) Monitoring and appraisal 2008 Holl K, Cairns JJr Handbook of Ecological Restoration: Principles of Restoration (eds) 2010 Apfelbaum SI, Haney AW Restoring Ecological Health to your Land 2010 L'Huillier L, Jaffré T, Wulff A Mines et Environnement en Nouvelle-Calédonie : les Milieux sur Substrats Ultramafiques et leur Restauration. 2010 Lamb D Regreening the Bare Hills: Tropical Forest Restoration in the Asia-Pacific Region Tropical dry forest restoration in Chiapas, Mexico and basic knowledge for native tree species: phenology, seed germination and seedling growth 2011 Becerra Vazquez AG, Ramierz-Marcial N, Holz SC Principles and Practice of Forest Landscape Restoration Case Studies from the Drylands of Latin America Newton AC, Tejedor N (eds) dryland forest restoration techniques Alvarez-Aquino C Suarez A, Blundo C, Smith-Ramirez C, Echeverria C, Cruz-Cruz E, Bolados G Armesto JJ, Heinemann K, Malizia L, Becarra P, del Castillo RF, Urrutia R of Forest Landscape Restoration Case Studies from the Drylands of Latin America Newton AC, Tejedor N (eds) Synthesis: principles and practice of forest landscape restoration 2011 Newton AC Principles and Practice of Forest Landscape Restoration Case Studies from the Drylands of Latin America Newton AC, Tejedor N (eds) Integrating scientific research with community needs to restore a forest landscape in Northern Thailand: A case study of Ban Mae Sa Mai 2012 Elliot S, Kuaraksa C, Tunjai P, Toktang T, Boonsai K, Sangkum S, Suwannaratana S, Blakesley D A Goal-Oriented Approach to Forest Landscape Restoration Stanturf J, Madsen P, Lamb D (eds) deforested and degraded areas in Africa Approach to Forest Landscape Restoration Stanturf J, Madsen P, Lamb D (eds) Restoring floodplain forests in Europe 2012 Hughes FMR, Gonzales del Tanago M, Mountford JO A Goal-Oriented Approach to Forest Landscape Restoration Stanturf J, Madsen P, Lamb D (eds) Vegetation response to tidal restoration 2012 Smith SM, Warren RS Tidal Marsh Restoration: A Synthesis of Science and Management Roman CT, Burdick DM (eds) Selecting suitable habitats for reintroductions: variation, change and the role of species distribution modelling 2012 Osborne PE, Seddon PJ Reintroduction Biology: Integrating Science and Management Ewen JG, Armstrong DP, Parker KA, Seddon PJ (eds) Open-cast mining reclamation 2005 Nicolau Ibarra JM, Moreno de las Heras M Forest restoration in Landscapes -Beyond Planting Trees Mansourian S, Vallauri Restoring tropical moist broad-leaf forests 2005 Lamb D Forest restoration in Landscapes -Beyond Planting Trees Mansourian S, Vallauri D, Dudley N (eds) Selecting tree species for plantation 2005 Montagnini F Forest restoration in Landscapes -Beyond Planting Trees Mansourian S, Vallauri D, Dudley N (eds) Burning and grazing management in a California grassland: growth, mortality, and recruitment of Nassella pulchra 2003 Dyer AR Restoration Ecology Bullying the bullies: the selective control of an exotic, invasive annual (Rapistrum rugosum) by oversowing with a competitive native 2005 Simmons, MT Restoration Ecology pulchella) Dune restoration introduces genetically distinct American beachgrass, Ammophila breviligulata, into a threatened local population 2010 Holmstrom RM, Etterson JR, Schimpf DJ Restoration Ecology Development of tree regeneration in fern-dominated forest understories after reduction of deer browsing 2002 De La Cretaz AL, Kelty MJ Restoration Ecology Soil conditions in natural, declining and restored heathlands influence plant-pollinator interactions of Calluna vulgaris 2012 de la Peña E, Van De Velde H, Lens L, Bonte D Restoration Ecology native plant 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Restoration Ecology Genecology of Holodiscus discolor (Rosaceae) in the Pacific Northwest, U.S.A. 2010 Horning ME, McGovern TR, Darris DC, Mandel NL Restoration Ecology Can an ecoregion serve as a seed transfer zone? Evidence from a common garden study with five native species 2011 Miller, SA, Bartow A, Gisler M, Ward K, Kaye TN Restoration Ecology adaptive traits in bottlebrush squirreltail in the northern intermountain west, United States Monaco TA Flowering phenology and genetic similarity among local and recently introduced populations of Andropogon gerardii in Ohio 2005 Selbo SM, Snow AA Restoration Ecology Effects of established perennial grasses on introduction of native forbs in California 2001 Brown CS, Bugg RL Restoration Ecology Woody encroachment removal from midwestern oak savannas alters understory diversity across space and time 2010 Brudvig LA Restoration Ecology magnesian limestone grassland: optimizing the Time for seed collection by vacuum harvesting Rimmer DL, Smith RS Vegetation colonization in a restoring tidal marsh: A remote sensing approach 2008 Tuxen KA, Schile LM, Kelly M, Siegel SW Restoration Ecology Considering local adaptation in issues of lepidopteran conservation -a review and recommendations 2011 Aardema ML, Scriber JM, Hellmann JJ American Midland Naturalist Reproductive phenology in a riparian rainforest in the south of Santa Catarina state, Brazil 2013 Cascaes MF, Citadini-Zanette V, Harter-Marques B Anais da Academia Brasileira de Ciencias Genetic variation between Lupinus elegans Kunth provenances, altitudal seed zoning and assisted migration 2012 Soto-Correa JC, Saenz-Romero C, Lindig-Cisneros R, Sanchez-Vargas N, Cruz-de-Leon J Agrociencia Genecology and seed zones for tapertip onion 2013 Johnson RC, Hellier BC, Vance-Borland KW Botany-Botanique Influence of flowering phenology on seed production in smooth cordgrass (Spartina alterniflora Loisel.) 2004 Fang XB, Subudhi PK, Venuto BC, Harrison SA, Ryan AB Aquatic Botany Seeding ecological restoration of tropical forests: priority setting under REDD+ 2012 Kettle CJ Biological Conservation Assessing the value of annual and perennial forage mixtures for bumblebees by direct observation and pollen analysis 2006 Carvell C, Westrich P, Meek WR, Pywell RF, Nowakowski M Apidologie Culture studies on early development of Lessonia trabeculata (Phaeophyceae, Laminariales): seasonality and acclimation to light and temperature 2013 Murua P, Westermeier R, Patino DJ, Mueller DG Phycological Research variation and seed zones for Bromus carinatus in the Blue Mountains of eastern Oregon, USA VJ, Mandel NL, St Clair JB, Vance-Borland KW Monitoring restored riparian vegetation: how can recent developments in remote sensing sciences help? 2013 Dufour S, Bernez I, Betbeder J, Corgne S, Hubert-Moy L, Nabucet J, Rapinel S, Sawtschuk J, Trolle C Knowledge and Management of Aquatic Ecosystems An invasive grass increases live fuel proportion and reduces fire spread in a simulated grassland 2013 McGranahan DA, Engle DM, Miller JR, Debinski DM Ecosystems Growth, herbivore distribution, and herbivore damage of timber trees in a tropical silvopastoral reforestation system 2013 Riedel J, Dorn S, Plath M, Mody K Annals of Forest Science of hawkmoths (Sphingidae) and Inga species (Fabaceae-Mimosoideae): implications for the restoration of the Atlantic forest of northeastern Brazil IC, Duarte JAJr, Lopes AV Conservation Phenological asynchronization as a restrictive factor of efficient pollination in clonal seed orchads of pedunculate oak (Quercus robur L.) 2011 Franjic J, Sever K, Bogdan S, Skvorc Z, Krstonosic D, Aleskovic I Croatian Journal of Forest Engineering Reproductive phenology of Miconia mirabilis (Melastomataceae) within three distinct physiognomies of Atlantic Forest, Bahia, Brazil 2012 Pessoa MS, De Vleeschouwer KM, Talora DC, Rocha L, Araujo AAM Biota Neotropica Biological flora of the British Isles: Gymnadenia 2012 Meekers T, Hutchings MJ, Honnay O, Journal of Ecology Landscape patterns of phenotypic variation and population structuring in a selfing grass, Elymus glaucus (blue wildrye) 2004 Erickson VJ, Mandel NL, Sorensen FC Canadian Journal of Batony Flower and fruit availability along a forest restoration gradient 2014 Garcia LC, Hobbs RJ, Maees dos Santos FA, Rodrigues RR Biotropica Sympatric species of Hibbertia (Dilleniaceae) vary in dormancy break and germination requirements: implications for classifying morphophysiological dormancy in Mediterranean biomes 2012 Hidayati SN, Walck JL, Merritt DJ, Turner SR, Turner DW, Dixon KW Annals of Botany Reproductive biology of a threatened Australian saltmarsh plant -Wilsonia backhousei 2012 Sommerville K, Pulkownik A, Burchett M Aquatic Botany wetlands naturally created equal? 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I: height growth, shoot phenology, and frost damage in seedlings 2009 Viveros-Viveros H, Saenz-Romero C, Vargas-Hernandez JJ, Lopez-Upton J, Ramirez-Valverde G, Santacruz-Varela A Forest Ecology and Management Restoration of Cymodocea nodosa (Uchria) Ascherson seagrass meadows through seed propagation: seed storage and influences of plant hormones and mineral nutrients on seedling growth in vitro 2010 Zarranz ME, Gonzalez-Henriquez N, Garcia-Jimenez P, Robaina RR Botanica Marina probabilities of larval amphibians and macroinvertebrates in isolated ponds Challenges to deep-water reproduction by lake trout: pertinence to restoration in Lake Michigan 2007 Janssen J, Marsden JE, Bronte CR, Jude DJ, Sitar SP, Goetz FW Journal of Great Lakes Research Reproductive phenology, seed germination and ex situ conservation of Pseudananas sagenarius in a semi-deciduous tropical forest fragment 2010 Vieira BC, Silveira FAO Plant Species Biology Impact of grazing management on hibernating caterpillars of the butterfly Melitaea cinxia in calcareous grasslands 2012 van Noordwijk CGE, Flierman Daphne E, Remke Eva, WallisDeVries MF, Berg MP Journal of Insect Conservation variation in Atlantic white-cedar (Chamaecyparis thyoides): early survival and growth in New Jersey and North Carolina plantations JE, Zimmermann GL, Smouse PE Management Diferencias en la produccion de frutos del roble Quercus humboldtii Bonpl. en dos bosque andinos de la cordillera oriental Colombiana 2010 González Melo A, Parrado Rosselli Á Colombia Forestal Day -time feeding ecology of Eulemur cinereiceps in the Agnalazaha Forest, Mahabo -Mananivo, Madagascar. 2010 Andriamaharoa H, Birkinshaw C, Reza L Madagascar Conservation & Development A review of the seabirds of Phillip Island in the Norfolk Island Group. 2010 Priddel D, Carlile N, Evans O, Evans B, McCoy H Notornis Germination phenology of some Great Basin 2010 Forbis TA Plant Species Biology species Clipping at early florescence is more efficient for controlling the invasive plant Spartina alterniflora 2009 Gao Y, Tang L, Wang J, Wang C, Liang Z, Li B, Chen J, Zhao B Ecological Research Genetic variation and productivity of Populus trichocarpa and its hybrids. 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X. Trait correlations in young interactions among native bunchgrasses and Donnellan SC, Paton black cottonwood from alien weeds -a review DC four river valleys in and synthesis Washington Ornamental attributes of 2001 Harris W Proceedings of the 20th paddock trees for Restoration of riparian 2002 Martin D, Chambers J Plant Ecology the natural variants of International Eucarpia woodland restoration in meadows degraded by Cordyline australis Symposium agricultural landscapes Seed germination of willow species from a livestock grazing: above-Succession and fire 1995 Howe HF Ecology 2003 Young JA, Clements CD Journal of Range Management and belowground season in experimental responses prairie plantings desert riparian buoyancy of seeds: the flood pulse concept ecosystem Response of early-flowering and late-1994 Howe HF Ecological Applications	x x x x x x x x x x x x x x x x x	exotic species	x x x x x	functions/traits	genetic x x x x x x x x x x x x x x x x x x x x x x x x x	provenance	x x x x x x x x x x x x x x x x x	Categories germination management monitoring x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x	x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x	seed h p m	x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x	sp interactions	x x x x x x x x	lack of knowledge

Acknowledgements

The authors would like to thank Megan F. King and Marjorie Sweetko for reviewing the English, and the Phenology Lab members, F. Mesléard, T. Dutoit, two reviewers and coordinating editor S. Allison

for improving previous versions. This work was supported by: EB -French Embassy / UNESP Rio Claro Chairs 2012 and 2014; STA -post-doctoral fellowships from UNESP PROPe and São Paulo Research Foundation (FAPESP) (grant #2014/12728-1); SLS -post-doctoral fellowship from PVE, CNPq (grant #150404/2016-6); LPCM -São Paulo Research Foundation (FAPESP): grants #2010/52113-5, #2013/50155-0, #2010/51307-0) and Research Productivity Fellowship from CNPq.

References green up in a cerrado savanna and its on-the-ground validation. in the copepod community of Lake Geneva.

Appendix S1-"Literature survey and reviewing process"

In February 2014, we used Google Books and the words "phenology" or "phenological" to perform a systematic search of forty-two books dealing with restoration (Table S1). We also performed a systematic survey of articles dealing with phenology in the context of restoration. We searched for articles in: 1) Restoration Ecology, the main journal publishing research on restoration and allowing the exchange of ideas among the many disciplines involved in the process of ecological restoration, using the term "phenolog*" in the full text, from 1993 to February 2014; and 2) the large database available in Web of Science, using the terms "restoration" AND "phenolog*" in the search topic, from 1985 to February 2014. After retrieving 404 chapters and papers, we removed 255 that only mentioned phenology without giving any details, or which mentioned phenology in contexts that were not relevant to restoration, or which were simply related to plant survival and growth after restoration without further insights into the role of phenology. We then reviewed the 149 relevant chapters and papers, and synthesized them by collecting data on the contexts in which the keywords "phenolog*" and "restor*" were mentioned. To do so, we classified them into categories according to the context in which the keywords were used. These categories were not pre-established: a new category was created every time a paper introduced the keywords in a new context. We ended up with nine categories as shown in Table S2. Each paper could be classified in several categories. The results below use the nine categories identified while reading the papers. S1. Title, year of publication and authors or editors of the 42 books dealing with restoration that were searched for the word "phenology" or "phenological". Dark grey lines correspond to books (9) that did not mention the word "phenology" or "phenological", light grey lines to books (7) that mentioned either one of them but in a context that is not directly relevant to restoration and white lines to books (26) that mentioned one of these two words in a context relevant to restoration (see Table S3 for details). S2. Categories adopted to classify the studies used in the literature review according to the different contexts in which phenology and restoration were addressed in the studies.

Appendix S1 -Table

Authors/Editors

Category

Definition based on papers surveyed exotic species potential negative interactions between target and exotic species phenology species interaction potential interactions between target and other species phenology functions/traits the restoration of particular ecosystem functions, plant functional or life-traits related to phenology genetic provenance differences in the phenology of target species depending on the seed provenance germination germination phenology management phenology within the context of applying a particular type of management on a restored site monitoring monitoring of reproductive phenology on the restored ecosystem (post-restoration monitoring) seed harvest, production and mixes collection of phenological data on the target species of their restoration project to improve seed collection, seed mixes or studied difference in the phenology of cultivated vs. wild species (pre-restoration monitoring) lack of knowledge there is not enough information on the phenology of the target species of their restoration project

Source