Glossary
Adaptive management | An iterative decision-making process in which scientific design and monitoring are integrated into management applications to systematically test assumptions in order to learn, reduce uncertainty, and adapt to achieve the management objective. |
Allele | One of the variant forms of a gene at a particular location (i.e., locus) on a chromosome. Different alleles produce variation in inherited characteristics, such as blood type. |
Assisted migration | The physical movement of species (e.g., individuals or seeds) by humans to new locations assessed to be suitable under changed climate or other environmental conditions. These locations may potentially be sites that have hosted other seed sources of the species, or new environments. |
Backcross | The breeding of a hybrid organism with one of its parents or with an organism genetically similar to a parent. |
Biocontrol | See “Biological control.” |
Biolistics | A technique that inserts DNA into plant cells by physical bombardment. |
Biological control | The reduction of pest populations through the use of natural enemies such as parasitoids, predators, pathogens, antagonists, or competitors to suppress pest populations. |
Biotech tree | A tree whose genome has been modified by a biotechnological approach. |
Biotechnology | A number of genetic modification methods other than selective breeding and sexually crossing organisms to endow new characteristics in organisms. These methods include transgenesis, cisgenesis, RNA interference, genome editing, and insertion of synthetic DNA to modify an organism’s DNA. |
Cisgenesis | The insertion of endogenous gene(s) or DNA fragments from a sexually compatible species into cells of a target species to create a new gene sequence. |
Conspecific | Organisms belonging to the same species. |
Ecosystem services | Goods and services that are of value to people, provided wholly or in part by ecosystems. |
Fitness | See “Genetic fitness.” |
Forest health | A condition that sustains the structure, composition, processes, function, productivity, and resilience of forest ecosystems over time and space. An assessment of this condition is based on the current state of knowledge and can be influenced by human needs, cultural values, and land management objectives. |
Foundational species | Species that exert a strong influence on other species and on ecosystem structure and function. |
Gene flow | The transfer of genetic information from one population into another population (via pollen or propagules in plants). |
Genetic fitness | A description of the ability to survive and reproduce, equal to the long-term average contribution to the gene pool by individuals having a particular genotype or phenotype. |
Genetic offset | A metric that identifies populations within a species’ distribution where local adaptation (gene × environment relationship) is most likely to be disrupted due to abiotic factors (e.g., climate change). |
Genetic resistance | The ability of an organism to exclude or overcome (to some degree or completely) the damaging effect of a pest. |
Genome | The complete sequence of the DNA in an organism. |
Genome editing | Specific modification of the DNA of an organism to create mutations or introduce new alleles or new genes. The four main classes of this approach are meganucleases, zinc finger nucleases, transcription activator-like effector nucleases (TALENs), and the clustered regularly interspaced short palindromic repeat (CRISPR) nuclease system. |
Genotype | All or part of the genetic constitution of an individual or group. |
Heterozygous | For diploid organisms, having two different alleles for a specific locus. |
High-impact species | Pest species that cause some combination of tree mortality, canopy thinning, growth loss, defoliation, and decreased reproduction or regeneration that significantly alters host population dynamics. |
Homozygous | For diploid organisms, having two identical alleles for a specific locus. |
Horizontal gene transfer | Movement of genes between populations of otherwise distinct species. |
Hybridization | The breeding of genetically unlike parents usually of closely related species to produce offspring. |
Hypovirulence | A kind of biological control in which the virulence of a pathogen is reduced by being infected with a virus. |
Instrumental value | The value of things measured by their usefulness to humans and human welfare. |
Intercross | The breeding of two organisms that are heterozygous. |
Intrinsic value | The value of things as ends in themselves, regardless of whether they are also useful as means to other ends and independent of their usefulness to humans. |
Invasive species | A species whose introduction does or is likely to cause economic or environmental harm or harm to human, animal, or plant health. |
Keystone species | A species whose influence on ecosystem function and diversity is disproportionate to its numerical abundance. |
Local adaptation | Adaptation of a population to the local environment where it has highest fitness compared to in other areas of the distribution range. |
Marker-assisted selection | The use of polymorphic DNA sequences to enhance the efficiency of breeding. |
Mast | The nuts, seeds, buds, and fruits produced by forest trees. |
Noninstrumental value | See “Intrinsic value.” |
Oomycetes | Fungus-like eukaryotic microorganisms that occupy saprophytic and pathogenic lifestyles. Many are plant pathogens, causing diseases such as seedling blights, damping-off, root rots, and foliar blights. |
Outcross | The breeding of two organisms of the same species that are genetically unrelated. |
Outplant | The action of planting trees in field conditions. |
Pest | Insects and pathogens that cause damage to forest trees. |
Phenology | The study of cyclic and seasonal natural phenomena, especially in relation to climate and plant and animal life. For plants, phenology refers to the study of effects of growth and development with specific timing such as flowering, bud set, bud break, and reproduction. |
Phenotype | The observable characteristics of an organism (i.e., how it appears outwardly and physiologically) resulting from the interaction of genotype and the environment. |
Phylogeography | The study of historical processes that may be responsible for contemporary geographic distributions of genealogical lineages. |
Polygenic | A trait that is controlled by multiple genes. |
Provenance | The specified location from which plants and their propagules were derived, comprising the environment to which they may be locally adapted. |
Qualitative resistance | Host genotypes show a discontinuous range of variation in resistance. Susceptible and resistant genotypes can be easily discerned, and influenced by one or more genes of major effect. |
Quantitative resistance | Host genotypes show a continuous range of variation in resistance, from extremely susceptible to fairly resistant, and are influenced by many minor genes. |
Quantitative trait locus | A region of the genome that contributes to a phenotype in a quantitative manner. |
RNA interference | A natural mechanism found in nearly all organisms in which the levels of transcripts are reduced or suppressed. |
Selective breeding | Modification of the genetic constitution of a plant through sexually crossing different genomes and selecting desirable genotypes to serve as parental lines in subsequent generations. |
Silviculture | The art and science of controlling the establishment, growth, composition, health, and quality of forests and woodlands to meet diverse needs and values. |
Synthetic DNA | Genes produced in the laboratory that are not based on any naturally occurring DNA sequences but that may have functional properties or utility for genetic engineering. |
Transgenesis | The insertion of foreign genes or DNA fragments into cells of a target species to create a new gene sequence. |
Virulence | The degree of damage or pathogenicity caused by a pathogen to a host species. |