{"id":37562,"date":"2026-09-16T23:50:00","date_gmt":"2026-09-17T03:50:00","guid":{"rendered":"https:\/\/www.ecoportal.net\/en\/?p=37562"},"modified":"2026-09-16T23:50:00","modified_gmt":"2026-09-17T03:50:00","slug":"jumping-worms-cocoons-overwinter-104-degree-heat","status":"publish","type":"post","link":"https:\/\/www.ecoportal.net\/en\/jumping-worms-cocoons-overwinter-104-degree-heat\/37562\/","title":{"rendered":"Soil in 38 states holds jumping worms whose cocoons ride out the winter that ends every adult, while the one treatment proven to reach inside a cocoon is three days of 104 degree heat"},"content":{"rendered":"<p>Push a hand into the top inch of ground under a maple.<\/p>\n<p>It should come up cool and matted, roots and half rotted leaves knitted into something that holds its shape.<\/p>\n<p>In an infested yard it comes up loose. The texture is&nbsp;<strong>coffee grounds<\/strong>, dry and granular, and it runs off the fingers like cereal.<\/p>\n<p>Underneath is bare mineral dirt. Above it, almost nothing left to rot.<\/p>\n<p>The layer that took a decade to build is&nbsp;<strong>simply gone<\/strong>, and the animal that ate it will not be there in April.<\/p>\n<h2>Why this worm does not work like the one in a bait cup<\/h2>\n<p>A nightcrawler burrows.<\/p>\n<p>It drags leaves down a permanent vertical shaft and works them into the mineral layer, mixing as it goes, which is the behavior every gardening book means when it calls worms good for soil.<\/p>\n<p>These feed at the surface instead.<\/p>\n<p>They stay in the litter, shred it where it lies, and leave behind&nbsp;<strong>loose castings<\/strong>&nbsp;with no crumb structure to hold water or seedling roots.<\/p>\n<p>They are also quick. Two generations in one season have been recorded in Wisconsin and in Maine, where a single annual cycle was long assumed.<\/p>\n<p>And they do not need a mate. Reproduction is parthenogenetic, so one animal riding in a pot of nursery stock is&nbsp;<strong>an entire population<\/strong>.<\/p>\n<h2>The object that does the actual invading<\/h2>\n<p>The adults are not the thing to plan around.<\/p>\n<p>Every one of them is finished by the first hard frost, and nothing at all overwinters as a worm.<\/p>\n<p>What overwinters is a cocoon about the size of a mustard seed, dark, irregular, and hard to tell from a grain of grit.<\/p>\n<p>It sits in the top few inches of soil, which is exactly the depth a trowel moves.<\/p>\n<p>So it travels in a pot of perennials, in bagged mulch, in the tread of a boot, and nobody stops it, because at&nbsp;<strong>that size<\/strong>&nbsp;there is nothing to stop.<\/p>\n<p>An infestation that shows up in July was usually&nbsp;<strong>carried home<\/strong>&nbsp;the previous autumn by somebody being helpful.<\/p>\n<h2>What the counts and the heat trials found<\/h2>\n<p>The litter number is the one worth memorizing. In Wisconsin forest plots, leaf litter fell by roughly&nbsp;<strong>95 percent<\/strong>&nbsp;where these worms had established, and nutrient turnover ran about twice as fast.<\/p>\n<p>Researchers describe the result as a fast release fertilizer, which sounds generous until you remember that a forest floor is a slow release system on purpose.<\/p>\n<p>On heat, the figures separate cleanly.<\/p>\n<p>Adults are finished by three days at 85 degrees. Cocoons are tougher, and work out of a Wisconsin arboretum puts the threshold at&nbsp;<strong>three days<\/strong>&nbsp;at 104 degrees.<\/p>\n<p>Commercial composting runs hotter than that, near 131 degrees, which is why finished commercial compost is considered safe and a backyard pile often is not.<\/p>\n<p>One widely shared figure, 104 degrees for two hours, is an outlier and should not be relied on.<\/p>\n<p>Two treatments that sounded plausible did nothing measurable in trials. Biochar failed. Diatomaceous earth failed. There is no registered pesticide for any of this.<\/p>\n<h2>The number in most coverage that traces to nothing<\/h2>\n<p>You will read that jumping worms are in 35 states.<\/p>\n<p>That figure has&nbsp;<strong>no source<\/strong>&nbsp;anybody can point to. The regional pest center that tracks the spread puts it at&nbsp;<strong>38 states<\/strong>, and even that overstates the picture, because distribution inside a state is patchy rather than general.<\/p>\n<p>One county can be thick with them while the next has none.<\/p>\n<p>Minnesota made possession and transport unlawful effective in the summer of 2024, and the reasoning behind that rule sits in the same litter research the&nbsp;<a href=\"https:\/\/www.fs.usda.gov\/about-agency\/features\/invasive-jumping-worms-can-change-their-world\" target=\"_blank\" rel=\"noopener\">federal foresters<\/a>&nbsp;summarize.<\/p>\n<p>Here is the part that gets left out. Nobody has documented reversing an established infestation anywhere, by any method, and state guidance is written around containment rather than removal, as&nbsp;<a href=\"https:\/\/www.dnr.state.mn.us\/invasives\/terrestrialanimals\/jumping-worm\/index.html\" rel=\"nofollow noopener\" target=\"_blank\">the state rules<\/a>&nbsp;make clear.<\/p>\n<p>The honest caveat runs the other way too. A 2020 study found the effects depend on which trees are overhead and are not uniformly bad, and one long running site has not yet shown a strong change in understory plants, the kind of slow signal that also shapes arguments about&nbsp;<a href=\"https:\/\/www.ecoportal.net\/en\/pollinators-flowers-wind-turbine-towers\/36700\/\">pollinators<\/a>&nbsp;and about what actually lives on a&nbsp;<a href=\"https:\/\/www.ecoportal.net\/en\/thismia-daemona-devil-flower-thailand\/36636\/\">forest floor<\/a>.<\/p>\n<h2>What is left to do in your own yard<\/h2>\n<p>Check what arrives before it goes in the ground, because almost every new infestation is delivered rather than grown.<\/p>\n<p>A mustard pour will bring anything in the top few inches to the surface in minutes, which makes a pot easy to screen.<\/p>\n<p>Keep soil, mulch and divided plants from moving between properties.<\/p>\n<p>Clear sheeting over bare ground through high summer holds the top inches above the cocoon threshold, which is the one control with evidence behind it.<\/p>\n<p>None of that is a fix.<\/p>\n<p>The useful reframing is that the adults writhing in the mulch are the&nbsp;<strong>visible half<\/strong>&nbsp;of the problem and the half that solves itself every autumn, while the half that decides next year is a scatter of grit sized objects nobody has ever been able to&nbsp;<strong>count or find<\/strong>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Push a hand into the top inch of ground under a maple. It should come up cool and matted, roots and half rotted leaves knitted into something that holds its shape. In an infested yard it comes up loose. The texture is&nbsp;coffee grounds, dry and granular, and it runs off the fingers like cereal. Underneath &#8230; <a title=\"Soil in 38 states holds jumping worms whose cocoons ride out the winter that ends every adult, while the one treatment proven to reach inside a cocoon is three days of 104 degree heat\" class=\"read-more\" href=\"https:\/\/www.ecoportal.net\/en\/jumping-worms-cocoons-overwinter-104-degree-heat\/37562\/\" aria-label=\"Read more about Soil in 38 states holds jumping worms whose cocoons ride out the winter that ends every adult, while the one treatment proven to reach inside a cocoon is three days of 104 degree heat\">Read more<\/a><\/p>\n","protected":false},"author":28,"featured_media":37756,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"rank_math_focus_keyword":"Soil","rank_math_title":"Soil in 38 states holds jumping worms whose cocoons ride out the winter that ends every adult, while the one treatment proven to reach inside a cocoon is three days of 104 degree heat","rank_math_description":"Ordinary bagged mulch is the main highway for invasive jumping worms now confirmed in 38 states, where their coffee-ground castings strip nutrients and ki","footnotes":""},"categories":[83],"tags":[],"class_list":["post-37562","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-earth"],"_links":{"self":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts\/37562","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/users\/28"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/comments?post=37562"}],"version-history":[{"count":3,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts\/37562\/revisions"}],"predecessor-version":[{"id":37757,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts\/37562\/revisions\/37757"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/media\/37756"}],"wp:attachment":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/media?parent=37562"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/categories?post=37562"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/tags?post=37562"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}