{"id":128,"date":"2026-03-14T15:33:49","date_gmt":"2026-03-14T14:33:49","guid":{"rendered":"https:\/\/ruudscheffer.nl\/home\/?page_id=128"},"modified":"2026-03-14T18:23:34","modified_gmt":"2026-03-14T17:23:34","slug":"dutch-elm-disease","status":"publish","type":"page","link":"https:\/\/ruudscheffer.nl\/home\/dutch-elm-disease\/","title":{"rendered":"Dutch Elm Disease"},"content":{"rendered":"\n<div class=\"wp-block-group alignfull has-global-padding is-layout-constrained wp-container-core-group-is-layout-0c9c989a wp-block-group-is-layout-constrained\" style=\"min-height:0vh;margin-top:0;margin-bottom:0;padding-top:var(--wp--preset--spacing--70);padding-right:var(--wp--preset--spacing--40);padding-bottom:var(--wp--preset--spacing--70);padding-left:var(--wp--preset--spacing--40)\">\n<div class=\"wp-block-group has-global-padding is-layout-constrained wp-container-core-group-is-layout-346627ba wp-block-group-is-layout-constrained\">\n<h2 class=\"wp-block-heading has-text-align-center has-large-font-size\" style=\"margin-right:0;margin-left:0;padding-right:0;padding-left:0\">Dutch elm disease (DED) devastated elms on an incredible scale. Breeding for resistance has resulted in a number of varieties with robust resistance, but for existing trees protection is difficult. Sanitation in combination with the biological control developed by my university group in the 1980s can limit losses of often valuable trees, for infection through beetle transmission to 0.1% annually as has been proven in 25+ years experience.<\/h2>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-group alignfull is-style-section-1 has-global-padding is-content-justification-left is-layout-constrained wp-container-core-group-is-layout-059fea23 wp-block-group-is-layout-constrained is-style-section-1--1\" style=\"margin-top:0;margin-bottom:0;padding-top:var(--wp--preset--spacing--80);padding-bottom:var(--wp--preset--spacing--80)\">\n<div class=\"wp-block-columns alignwide is-layout-flex wp-container-core-columns-is-layout-66fad18a wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"padding-right:var(--wp--preset--spacing--50);flex-basis:45%\">\n<div class=\"wp-block-group has-global-padding is-layout-constrained wp-block-group-is-layout-constrained\" style=\"margin-top:-12vw\"><\/div>\n\n\n\n<figure class=\"wp-block-image aligncenter size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"762\" height=\"1024\" src=\"https:\/\/ruudscheffer.nl\/wp-content\/uploads\/2026\/03\/DED-twig-symptoms-762x1024.jpg\" alt=\"\" class=\"wp-image-132\" style=\"aspect-ratio:0.7441526196645224;width:263px;height:auto\" srcset=\"https:\/\/ruudscheffer.nl\/wp-content\/uploads\/2026\/03\/DED-twig-symptoms-762x1024.jpg 762w, https:\/\/ruudscheffer.nl\/wp-content\/uploads\/2026\/03\/DED-twig-symptoms-223x300.jpg 223w, https:\/\/ruudscheffer.nl\/wp-content\/uploads\/2026\/03\/DED-twig-symptoms-768x1032.jpg 768w, https:\/\/ruudscheffer.nl\/wp-content\/uploads\/2026\/03\/DED-twig-symptoms-1143x1536.jpg 1143w, https:\/\/ruudscheffer.nl\/wp-content\/uploads\/2026\/03\/DED-twig-symptoms-1524x2048.jpg 1524w, https:\/\/ruudscheffer.nl\/wp-content\/uploads\/2026\/03\/DED-twig-symptoms-scaled.jpg 1905w\" sizes=\"auto, (max-width: 762px) 100vw, 762px\" \/><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-vertically-aligned-top is-layout-flow wp-block-column-is-layout-flow\" style=\"padding-right:0;padding-left:0;flex-basis:80%\">\n<p class=\"is-style-text-subtitle has-large-font-size is-style-text-subtitle--2\">DED is caused by the fungal pathogen <em>Ophistoma ulmi<\/em>. Spores of this fungus are transported by elm bark beetles feeding on young twigs. Therefore the first symptoms typically are wilting twigs. When the disease spreads, ultimately the whole tree wilts and dies. A complicating factor can be that dying trees can spread the disease to neighboring elms through root contacts; only mechanical disruption of such root contacts stops this type of disease transmission.<\/p>\n\n\n\n<p>An effective biocontrol for DED infections by elm bark beetles has proven its value, see:<\/p>\n\n\n\n<p class=\"has-medium-font-size\"><a href=\"https:\/\/apsjournals.apsnet.org\/doi\/abs\/10.1094\/PDIS-92-2-0192\" data-type=\"link\" data-id=\"https:\/\/apsjournals.apsnet.org\/doi\/abs\/10.1094\/PDIS-92-2-0192\">R.J. Scheffer, J.G.W.F. Voeten, R.P. Guries. 2008. Biological Control of Dutch Elm Disease. Plant Disease 92, 192-200.<\/a><\/p>\n\n\n\n<p class=\"has-medium-font-size\"><a href=\"https:\/\/dutchtrig.com\/\" data-type=\"link\" data-id=\"https:\/\/dutchtrig.com\/\">The biocontrol product is marketed as &#8216;Dutch Trig&#8217;, see Dutchtrig.com<\/a><\/p>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"458\" src=\"https:\/\/ruudscheffer.nl\/wp-content\/uploads\/2026\/03\/DEDsymptomsandbeetles-1-1024x458.jpg\" alt=\"\" class=\"wp-image-149\" srcset=\"https:\/\/ruudscheffer.nl\/wp-content\/uploads\/2026\/03\/DEDsymptomsandbeetles-1-1024x458.jpg 1024w, https:\/\/ruudscheffer.nl\/wp-content\/uploads\/2026\/03\/DEDsymptomsandbeetles-1-300x134.jpg 300w, https:\/\/ruudscheffer.nl\/wp-content\/uploads\/2026\/03\/DEDsymptomsandbeetles-1-768x344.jpg 768w, https:\/\/ruudscheffer.nl\/wp-content\/uploads\/2026\/03\/DEDsymptomsandbeetles-1-1536x687.jpg 1536w, https:\/\/ruudscheffer.nl\/wp-content\/uploads\/2026\/03\/DEDsymptomsandbeetles-1-2048x917.jpg 2048w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Dutch elm disease (DED) devastated elms on an incredible scale. Breeding for resistance has resulted in a number of varieties with robust resistance, but for existing trees protection is difficult. Sanitation in combination with the biological control developed by my university group in the 1980s can limit losses of often valuable trees, for infection through [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-128","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/ruudscheffer.nl\/home\/wp-json\/wp\/v2\/pages\/128","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ruudscheffer.nl\/home\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/ruudscheffer.nl\/home\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/ruudscheffer.nl\/home\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ruudscheffer.nl\/home\/wp-json\/wp\/v2\/comments?post=128"}],"version-history":[{"count":9,"href":"https:\/\/ruudscheffer.nl\/home\/wp-json\/wp\/v2\/pages\/128\/revisions"}],"predecessor-version":[{"id":151,"href":"https:\/\/ruudscheffer.nl\/home\/wp-json\/wp\/v2\/pages\/128\/revisions\/151"}],"wp:attachment":[{"href":"https:\/\/ruudscheffer.nl\/home\/wp-json\/wp\/v2\/media?parent=128"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}