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October 13, 2025<\/p>\n
2 min read<\/p>\n
Scientists Map Microbiome Hidden Deep inside Tree Trunks<\/p>\n
Trees\u2019 inner heartwood harbors methane-producing microbes adapted to oxygen-poor swamps and cow guts<\/p>\n
By Saugat Bolakhe edited by Sarah Lewin Frasier<\/span><\/p>\n Darrell Gulin\/Getty Images<\/p>\n Scientists have mapped microbe populations in human guts, deep-sea ecosystems and even clouds. Yet the microbial communities inside tree trunks have remained largely unseen until now. For a recent study in Nature, researchers analyzed about 150 trees to map the communities of microbes living in 16 species. They estimate that a single mature tree hosts about one trillion bacteria in its trunk \u201cmicrobiome,\u201d with distinct communities living in different layers.<\/p>\n Most intriguing, the scientists found anaerobic bacteria\u2014bacteria that don\u2019t consume oxygen\u2014producing methane in the deep heartwood. \u201cIt turned out what\u2019s living inside the trees was really different from what we found anywhere else in the forest,\u201d says the study\u2019s co-lead author, Jonathan Gewirtzman, an ecosystem ecologist at Yale University. The trees\u2019 interior population, he says, was more akin to that of a wetland.<\/p>\n For a long time plant tissues were thought to be sterile. When that was disproved in the early 1900s, researchers focused largely on roots, where many bacteria and fungi are involved in soil-based nutrient cycling. Whatever might be living within a plant\u2019s shoots, trunks and leaves was mostly ignored.<\/p>\n If you’re enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.<\/p>\n To examine the trunk\u2019s hidden biome, Gewirtzman and his colleagues drilled into living tree trunks to extract thin core samples, which they immediately froze with dry ice to halt microbial activity. They then separated the cores into sapwood and heartwood (a tree trunk\u2019s middle and innermost layers, respectively), ground the frozen wood into powder and sequenced the bacteria in each layer. To study the activity of living microbes, they also sealed holes drilled into trees and later measured gases such as methane and nitrous oxide emitted by different layers.<\/p>\n The researchers learned that when trees are evolutionarily close, they tend to have similar microbiomes. And the team found a surprise deep inside the trunks: \u201cIn the older and inner heartwood,\u201d Gewirtzman says, \u201cwe saw microbes more like what you\u2019d find in a wetland\u2014anaerobic bacteria and methane producers,\u201d species suited to a waterlogged and oxygen-poor environment. Some bacteria in the outer layers may consume part of that methane, the researchers found, but the study suggests that methane-producing and nitrous oxide\u2013producing bacteria inside trees could still create greenhouse gas emissions scientists should figure into calculations.<\/p>\n \u201cIt is a really nice study, as they did something different from most: comparing the inner wood versus the outer wood,\u201d says plant microbiologist Sharon Lafferty Doty of the University of Washington. Doty adds that chemicals used in modern agriculture erode the health of plant microbiomes. \u201cBy studying these natural plant-microbe partnerships, we can understand which bacteria are important and active to add back into our agricultural system,\u201d she says.<\/p>\n If you enjoyed this article, I\u2019d like to ask for your support. 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I hope you\u2019ll support us in that mission.<\/p>\n","protected":false},"excerpt":{"rendered":" October 13, 2025 2 min read Scientists Map Microbiome Hidden Deep inside Tree Trunks Trees\u2019 inner heartwood harbors methane-producing microbes adapted to oxygen-poor swamps and cow guts By Saugat Bolakhe edited by Sarah Lewin Frasier Darrell Gulin\/Getty Images Scientists have mapped microbe populations in human guts, deep-sea ecosystems and even clouds. Yet the microbial communities<\/p>\n","protected":false},"author":1,"featured_media":27794,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[50],"tags":[5604,3435,2415,16554,384,3751,16555],"class_list":{"0":"post-27793","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-environment","8":"tag-deep","9":"tag-hidden","10":"tag-map","11":"tag-microbiome","12":"tag-scientists","13":"tag-tree","14":"tag-trunks"},"_links":{"self":[{"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/posts\/27793","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=27793"}],"version-history":[{"count":0,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/posts\/27793\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/media\/27794"}],"wp:attachment":[{"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=27793"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=27793"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=27793"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}On supporting science journalism<\/h2>\n
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