Pioneer Species : Species that are the first to colonize a new site or a new ecosystem. They are generally shade-intolerant and need a lot of sunlight in order to grow. Poplars and birches are pioneer species
British Columbia Ministry of Forests and Range, Acronyms and Initialisms for Forestry Terms in British Columbia, Canada 2008. http://www.for.gov.bc.ca/hfd/library/documents/acr onyms/ & http://www.for.gov.bc.ca/hfd/library/documents/glo ssary/Glossary.pdf, (For Fr - Canad) {16}