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How many tree species are there? More than you can shake a stick at, new database reveals

You’ve probably heard of an oak tree (like the one shown here), but have you ever heard of a jabuticaba or boojum tree? Trees are important for timber, food, and medicine, but getting a handle on the world’s thousands of tree species is a tough task. Up until this year, there's been no complete census. Now, researchers have published the first global database of tree species and their geographical ranges, a “huge scientific effort,” the team reports in the Journal of Sustainable Forestry. The scientists compiled the searchable online archive, which includes over 60,000 tree species, using data from a variety of sources such as museums, botanical gardens, and agricultural institutions. They found that Brazil, Colombia, and Indonesia were the countries with the most tree species—each is home to at least 5000. And nearly 60% of the world’s trees are native to just one country, the team noted. This database, which will be continuously updated, should allow researchers, policymakers, and the public to better monitor tree diversity and efforts to conserve specific species in forests, the scientists suggest. It will also form the basis of the Global Tree Assessment, an effort to document the conservation status of each tree species before the end of the decade.