{ "type": "mediaitem", "identifier": "mediaitem_2120", "subtype": "wmammodularcontent_gkn_dossier", "title": "Essentak­sterfte", "navtitle": "", "url": "/nl/groenkennisnet/dossier/essentaksterfte-dossier", "language": "nl_NL", "sections": [ { "identifier": "pagesection_145298", "title": "GKN Configuratie", "link": "/nl/groenkennisnet/paginasectie?pagesectionid=145298&tsobjectid=145298" }, { "identifier": "pagesection_145419", "title": "GKN Menu", "link": "/nl/groenkennisnet/paginasectie?pagesectionid=145419&tsobjectid=145419" }, { "identifier": "pagesection_145379", "title": "GKN Footer logo's", "link": "/nl/groenkennisnet/paginasectie?pagesectionid=145379&tsobjectid=145379" }, { "identifier": "pagesection_145248", "title": "GKN Footer", "link": "/nl/groenkennisnet/paginasectie?pagesectionid=145248&tsobjectid=145248" }, { "identifier": "pagesection_145401", "title": "GKN Footer legal", "link": "/nl/groenkennisnet/paginasectie?pagesectionid=145401&tsobjectid=145401" } ], "metadata" : { "id": 18705, "identifier": "mediaitem_2120", "contenttype": "wmammodularcontent_gkn_dossier", "contenttype_title": "contenttype_wmammodularcontent_gkn_dossier", "url": "/nl/groenkennisnet/dossier/essentaksterfte-dossier", "title": "Essentak­sterfte", "lead": "Sinds 2010 is essentaksterfte, ook wel essensterfte, in Nederland waargenomen. Deze ziekte wordt veroorzaakt door de uit Azië afkomstige schimmel Hymenoscyphus fraxineus (oude naam: Chalara fraxinea). Essentaksterfte is nu door heel Nederland en Noord-West Europa verspreid. Op dit moment is er nog geen adequate oplossing om de ziekte te bestrijden.\nHet is belangrijk om de es te behouden omdat de inheemse es, die erg gevoelig is voor de ziekte, van grote waarde is voor de biodiversiteit en een belangrijke gebruiksboom is.", "leadimage": { "source": "https://api.groenkennisnet.nl/upload_mm/f/5/c/2627_fullimage_essenblad.jpg", "width": 1280, "height": 853, "focuspoint-x": -1, "focuspoint-y": -1, "alternative_text": "", "photographer": "", "photographer_hyperlink": "https://pixabay.com/nl/users/vjgalaxy-8110364/", "photo_license": "Pixabay License", "photo_license_hyperlink": "https://pixabay.com/nl/service/license/", "source_info": "", "source_info_hyperlink": "", "keywords": [] }, "publication_date": "2021-09-13T10:48+02:00", "lastmodified_date": "2025-10-01T12:25+02:00", "expiration_date": "", "tags": [ "gkn_home", "gkn_groenvoorziening", "gkn_terreinbeheer", "Dossier", "Dutch", "gkn_boomverzorging", "webi_invasieveexoten" ], "copyright": "", "external_id": "", "item_metadata": { "contentsubtype": "Dossier", "theme": [ "gkn_home", "gkn_groenvoorziening", "gkn_boomverzorging", "gkn_terreinbeheer" ], "keywords": [], "video_header": "https://www.youtube.com/watch?v=pze4V8Sjlrs", "gkn_organization": { "title": "Groen Kennisnet", "url": "/nl/groenkennisnet/nieuwsitem/groen-kennisnet-organisatie" }, "contactperson": { "title": "Redactie Groen Kennisnet", "url": "/nl/groenkennisnet/nieuwsitem/redactie-groen-kennisnet" }, "experts": [{ "title": "Jelle Hiemstra", "url": "/nl/groenkennisnet/persoon/jelle-hiemstra" }], "link_extra_image": "", "last_update": "" } }, "contents": [ { "area": "beginhier", "title": "Begin hier", "contentarea_template": { "id": "contenttemplate_dossier", "name": "contenttemplate_dossier"},"background": false,"contentarea_leadtext": "","image": { "source": "https://api.groenkennisnet.nl/upload_mm/1/8/2/4065_fullimage_fraxinus-excelsior-g9486e9c1a_1280.jpg", "width": 1280, "height": 960, "focuspoint-x": -1, "focuspoint-y": -1, "alternative_text": "Es boom - WikimediaImages via Pixabay", "photographer": "WikimediaImages", "photographer_hyperlink": "https://pixabay.com/users/wikimediaimages-1185597/", "photo_license": "Pixabay licence", "photo_license_hyperlink": "https://pixabay.com/nl/service/license-summary/", "source_info": "Pixabay", "source_info_hyperlink": "https://pixabay.com/photos/fraxinus-excelsior-ash-european-ash-844653/", "keywords": [ "Es", "essen", "boom", "fraxinus", "veld", "gras", "sloot" ] }, "elements": [ { "identifier": "element_545782", "type": "modularcontent", "gkzindexmanual": { "title": "", "gkz_content_id": [ "1224613", "1165084", "551760", "495784" ] } } , { "id": 545783, "url": "https://api.groenkennisnet.nl/web/searchretrieve/v1/json", "type": "search_retrieve_query", "title": "Nieuwsberichten van Groen Kennisnet", "query": "{\r\n"search": {\r\n"types": ["wmammodularcontent_gkn_news"],\r\n"from": 1,\r\n"to": 3,\r\n"wmamodularcontent0gkn_news0related_dossier_raw": "mediaitem-2120",\r\n"sortBy": "publicationDate",\r\n"sortOrder": "desc"\r\n}\r\n}", "frontendPresentation": "default", "useSSL": "true" } ] }, { "area": "symptomen", "title": "Symptomen", "contentarea_template": { "id": "contenttemplate_dossier", "name": "contenttemplate_dossier"},"background": true,"contentarea_leadtext": "De schimmel infecteert de bomen via het blad. De eerste symptomen zijn bladvlekjes gevolgd door verkleuring van de nerven, en het geheel of gedeeltelijk afsterven van het blad. ","image": { "source": "https://api.groenkennisnet.nl/upload_mm/4/1/b/3797_fullimage_leaves-g9e027aeff_1280.jpg", "width": 1280, "height": 853, "focuspoint-x": -1, "focuspoint-y": -1, "alternative_text": "Es bladeren zon - Hans via Pixabay", "photographer": "Hans", "photographer_hyperlink": "https://pixabay.com/users/hans-2/", "photo_license": "Pixabay licence", "photo_license_hyperlink": "https://pixabay.com/nl/service/license-summary/", "source_info": "Pixabay", "source_info_hyperlink": "https://pixabay.com/photos/leaves-green-tree-ash-common-ash-141567/", "keywords": [ "es", "essen", "blad", "bladeren", "boom", "bomen", "fraxinus" ] }, "elements": [ { "type": "text", "html": "

Verdere aantasting is te herkennen aan donkere verkleuringen in de bast, beginnend bij de bladaanzet en takaanzet. Onder de schors is duidelijk te zien dat de bast afgestorven is. Bij uitbreiding rond de tak, sterft het topdeel van de tak af. Bij een ernstigere vorm van aantasting kan dit uiteindelijk leiden tot het afsterven van de gehele boom.<\/p>

De aantasting treedt vooral op in jonge essenaanplant, in de uitloop van afgezette essenstobben in hakhout en in gedunde essenopstanden. Oudere essen kunnen echter ook aangetast worden in kroon- en stronkuitlopers.<\/p>" } , { "identifier": "element_545786", "type": "modularcontent", "gkzindexmanual": { "title": "", "gkz_content_id": [ "12013", "1232098", "647805", "987891" ] } } , { "identifier": "element_545787", "type": "modularcontent", "GKZ_searchelementquery": { "gkz_linktext": "Meer bronnen over essentaksterfte", "gkz_search_query": "https://library.wur.nl/WebQuery/gkn3?q=essentaksterfte&wq_srt_desc=score" } } ] }, { "area": "gevoeligheidvandesoorten", "title": "Gevoeligheid van de soorten", "contentarea_template": { "id": "contenttemplate_dossier", "name": "contenttemplate_dossier"},"background": false,"contentarea_leadtext": "Niet alle soorten en ook niet alle cultivars worden aangetast door de schimmel. Uit onderzoek is duidelijk geworden dat de schimmel zich verspreidt via sporen in de lucht en vaak over grote afstanden. Er zijn ook aanwijzingen dat sterke snoei de essen extra gevoelig maakt voor de infectie.","image": { "source": "https://api.groenkennisnet.nl/upload_mm/6/2/5/3548_fullimage_fraxinus-excelsior-g4e53c11f0_1280.jpg", "width": 1280, "height": 960, "focuspoint-x": -1, "focuspoint-y": -1, "alternative_text": "Es blad - WikimediaImages via Pixabay", "photographer": "WikimediaImages", "photographer_hyperlink": "https://pixabay.com/users/wikimediaimages-1185597/", "photo_license": "Pixabay licence", "photo_license_hyperlink": "https://pixabay.com/nl/service/license-summary/", "source_info": "Pixabay", "source_info_hyperlink": "https://pixabay.com/photos/fraxinus-excelsior-ash-common-ash-844492/", "keywords": [ "es", "essen", "blad", "bladeren", "boom", "bomen", "fraxinus" ] }, "elements": [ { "type": "text", "html": "

Aantastingen door de schimmel zijn bekend bij de volgende soorten essen:<\/p>