{"id":2395,"date":"2026-03-14T13:18:34","date_gmt":"2026-03-14T13:18:34","guid":{"rendered":"https:\/\/profound.nl\/?p=2395"},"modified":"2026-03-14T13:20:21","modified_gmt":"2026-03-14T13:20:21","slug":"pda-dlt-pile-testing-explained-astm-d4945-dynamic-load-testing-2","status":"publish","type":"post","link":"https:\/\/profound.nl\/de\/pda-dlt-pile-testing-explained-astm-d4945-dynamic-load-testing-2\/","title":{"rendered":"Interpreting WOODPECKER Measurements"},"content":{"rendered":"<div data-elementor-type=\"wp-post\" data-elementor-id=\"2395\" class=\"elementor elementor-2395\" data-elementor-post-type=\"post\">\n\t\t\t\t<div class=\"elementor-element elementor-element-221ff94 e-flex e-con-boxed e-con e-parent\" data-id=\"221ff94\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-a19d88a elementor-widget elementor-widget-html\" data-id=\"a19d88a\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"html.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<style>\r\n  :root {\r\n    --pf-blue-900: #083a54;\r\n    --pf-blue-800: #0b4f73;\r\n    --pf-blue-700: #0f6e9c;\r\n    --pf-blue-600: #1586b7;\r\n    --pf-sky-500: #27a7d8;\r\n    --pf-text: #0f2230;\r\n    --pf-muted: #5c6b76;\r\n    --pf-border: #e6edf2;\r\n    --pf-card: #ffffff;\r\n    --pf-bg: #f6f9fc;\r\n    --pf-radius: 22px;\r\n  }\r\n\r\n  .pf-wrap {\r\n    font-family: system-ui, -apple-system, Segoe UI, Roboto, Arial, \"Helvetica Neue\", sans-serif;\r\n    color: var(--pf-text);\r\n    line-height: 1.55;\r\n  }\r\n\r\n  .pf-container {\r\n    width: min(1140px, 92vw);\r\n    margin: 0 auto;\r\n  }\r\n\r\n  \/* HERO *\/\r\n  .pf-hero {\r\n    background: linear-gradient(180deg, var(--pf-blue-900) 0%, var(--pf-blue-700) 70%, var(--pf-sky-500) 100%);\r\n    border-radius: 28px;\r\n    overflow: hidden;\r\n    box-shadow: 0 18px 40px rgba(8, 58, 84, .22);\r\n    margin-bottom: 40px;\r\n  }\r\n\r\n  .pf-hero-inner {\r\n    padding: clamp(26px, 4vw, 54px);\r\n    display: grid;\r\n    grid-template-columns: 1.15fr .85fr;\r\n    gap: clamp(18px, 3vw, 42px);\r\n    align-items: center;\r\n  }\r\n\r\n  .pf-hero h1 {\r\n    color: #fff;\r\n    font-size: clamp(30px, 3.4vw, 46px);\r\n    line-height: 1.08;\r\n    margin: 0 0 10px 0;\r\n    letter-spacing: .2px;\r\n  }\r\n\r\n  .pf-hero .pf-hero-subtitle {\r\n    color: rgba(255, 255, 255, .92);\r\n    font-weight: 800;\r\n    letter-spacing: .2px;\r\n    margin: 0 0 14px 0;\r\n    font-size: 16px;\r\n  }\r\n\r\n  .pf-hero p {\r\n    color: rgba(255, 255, 255, .88);\r\n    font-size: 16.5px;\r\n    margin: 0 0 18px 0;\r\n    max-width: 70ch;\r\n  }\r\n\r\n  .pf-actions {\r\n    display: flex;\r\n    flex-wrap: wrap;\r\n    gap: 12px;\r\n    margin-top: 8px;\r\n  }\r\n\r\n  .pf-btn {\r\n    display: inline-flex;\r\n    align-items: center;\r\n    justify-content: center;\r\n    padding: 12px 20px;\r\n    border-radius: 999px;\r\n    font-weight: 700;\r\n    text-decoration: none;\r\n    font-size: 14px;\r\n    letter-spacing: .2px;\r\n    transition: transform .08s ease, box-shadow .12s ease, opacity .12s ease;\r\n    user-select: none;\r\n    cursor: pointer;\r\n    max-width: 100%;\r\n    white-space: normal;\r\n    text-align: center;\r\n    line-height: 1.25;\r\n    overflow-wrap: anywhere;\r\n    word-break: break-word;\r\n  }\r\n\r\n  .pf-btn:hover { transform: translateY(-1px); 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}\r\n\r\n  @media (max-width: 900px) {\r\n    .pf-hero-inner { grid-template-columns: 1fr; }\r\n    .pf-card { grid-column: span 12; }\r\n    .pf-split { grid-template-columns: 1fr; }\r\n    .pf-hero-tag { position: static; text-align: left; margin-top: 10px; }\r\n    .pf-cta { flex-direction: column; align-items: flex-start; }\r\n  }\r\n\r\n  @media (max-width: 560px) {\r\n    .pf-actions {\r\n      flex-direction: column;\r\n      align-items: stretch;\r\n    }\r\n    .pf-btn {\r\n      width: 100%;\r\n      padding: 12px 16px;\r\n    }\r\n  }\r\n<\/style>\r\n\r\n<div class=\"pf-wrap\">\r\n  <div class=\"pf-container\">\r\n\r\n    <!-- HERO -->\r\n    <section class=\"pf-hero\" aria-label=\"WOODPECKER hero\">\r\n      <div class=\"pf-hero-inner\">\r\n        <div>\r\n          <h1>Interpreting WOODPECKER Measurements<\/h1>\r\n          <p class=\"pf-hero-subtitle\">How to estimate wood density from mm readings and what influences the result<\/p>\r\n          <p>\r\n            The WOODPECKER is used to assess wood condition by measuring penetration depth at a fixed impact energy.\r\n            In practice, users often ask the same question: how do you interpret a reading in millimetres, and can that value be linked to wood density?\r\n          <\/p>\r\n          <p>\r\n            Although Profound does not provide an official species database or standard conversion table with the WOODPECKER,\r\n            published research and long-standing Pilodyn practice offer a solid basis for estimating indicative wood density from penetration depth.\r\n            This article explains the principle, the available conversion equations, the practical density classes, and the key factors that affect measurement quality.\r\n          <\/p>\r\n\r\n          <div class=\"pf-actions\">\r\n            <a class=\"pf-btn pf-btn-hero-primary\" href=\"#conversion\">Conversion equations<\/a>\r\n            <a class=\"pf-btn pf-btn-hero-ghost\" href=\"#contact\">Kontakt<\/a>\r\n          <\/div>\r\n        <\/div>\r\n\r\n        <div class=\"pf-hero-media\">\r\n          <div class=\"pf-device\">\r\n            <img decoding=\"async\"\r\n              src=\"https:\/\/profound.nl\/wp-content\/uploads\/2025\/04\/De-Specht-1024x768.jpg\"\r\n              alt=\"The Profound WOODPECKER system\"\r\n              loading=\"lazy\"\r\n              onerror=\"this.src='https:\/\/profound.nl\/wp-content\/uploads\/2025\/04\/Profound-017groot-scaled-1-300x192.jpg'\"\r\n            \/>\r\n          <\/div>\r\n          <div class=\"pf-hero-tag\">\r\n            <div class=\"pf-model\">WOODPECKER<\/div>\r\n            <div class=\"pf-sub\">Forest &amp; Standard pin<\/div>\r\n          <\/div>\r\n        <\/div>\r\n      <\/div>\r\n    <\/section>\r\n\r\n    <!-- 1 -->\r\n    <section class=\"pf-section\" id=\"principle\">\r\n      <div class=\"pf-surface\">\r\n        <p class=\"pf-kicker\">1. Measurement principle<\/p>\r\n        <h2 class=\"pf-h2\">Why penetration depth says something about wood density<\/h2>\r\n        <p class=\"pf-lead\">\r\n          The WOODPECKER works with a spring-loaded steel pin that penetrates the wood at a fixed energy.\r\n          The deeper the pin penetrates, the lower the resistance of the material. In general terms, this means that\r\n          denser and harder wood gives a lower mm reading, while softer, wetter, degraded, or decayed wood gives a higher reading.\r\n        <\/p>\r\n\r\n        <div class=\"pf-grid\">\r\n          <div class=\"pf-card\">\r\n            <div class=\"pf-icon\">01<\/div>\r\n            <h3>Fixed-energy impact<\/h3>\r\n            <p>\r\n              The instrument uses a controlled spring force and pin velocity, so readings can be compared when the same procedure is followed consistently.\r\n            <\/p>\r\n          <\/div>\r\n          <div class=\"pf-card\">\r\n            <div class=\"pf-icon\">02<\/div>\r\n            <h3>Inverse relationship<\/h3>\r\n            <p>\r\n              Penetration depth is inversely related to wood density. Lower penetration generally indicates higher density and stronger wood structure.\r\n            <\/p>\r\n          <\/div>\r\n          <div class=\"pf-card\">\r\n            <div class=\"pf-icon\">03<\/div>\r\n            <h3>Indicative assessment<\/h3>\r\n            <p>\r\n              The method is especially useful for ranking, screening, trend monitoring, forest management, and first-line condition checks.\r\n            <\/p>\r\n          <\/div>\r\n          <div class=\"pf-card\">\r\n            <div class=\"pf-icon\">04<\/div>\r\n            <h3>Not a lab replacement<\/h3>\r\n            <p>\r\n              WOODPECKER readings provide an estimate, not a direct laboratory density determination or a standalone structural design value.\r\n            <\/p>\r\n          <\/div>\r\n        <\/div>\r\n\r\n        <div class=\"pf-callout\">\r\n          <p style=\"margin:0; color: var(--pf-muted); font-size: 14.8px;\">\r\n            Decades of literature on Pilodyn-type instruments support this relationship, with reported correlations between penetration depth and wood density ranging from moderate to strong depending on species, age, and field conditions.\r\n          <\/p>\r\n        <\/div>\r\n      <\/div>\r\n    <\/section>\r\n\r\n    <!-- 2 -->\r\n    <section class=\"pf-section\" id=\"conversion\">\r\n      <div class=\"pf-surface\">\r\n        <p class=\"pf-kicker\">2. Converting mm to density<\/p>\r\n        <h2 class=\"pf-h2\">Generalised regression equations for WOODPECKER readings<\/h2>\r\n\r\n        <p class=\"pf-lead\">\r\n          Profound does not supply one official universal conversion table for all species and all conditions. However, published literature provides practical regression equations that can be used to estimate basic wood density from penetration depth.\r\n        <\/p>\r\n\r\n        <div class=\"pf-table-wrap\">\r\n          <table class=\"pf-table\" aria-label=\"Regression equations\">\r\n            <thead>\r\n              <tr>\r\n                <th>Pin diameter<\/th>\r\n                <th>Regression equation<\/th>\r\n                <th>Anmeldung<\/th>\r\n              <\/tr>\r\n            <\/thead>\r\n            <tbody>\r\n              <tr>\r\n                <td><strong>\u00d8 2.5 mm<\/strong> (Forest pin)<\/td>\r\n                <td><strong>Density = 700 \u2212 (18.5 \u00d7 depth_mm)<\/strong><\/td>\r\n                <td>Primarily relevant for forest and standing tree applications<\/td>\r\n              <\/tr>\r\n              <tr>\r\n                <td><strong>\u00d8 5 mm<\/strong> (Standard pin)<\/td>\r\n                <td><strong>Density = 660 \u2212 (14.5 \u00d7 depth_mm)<\/strong><\/td>\r\n                <td>Useful as a general reference for standard pin measurements<\/td>\r\n              <\/tr>\r\n            <\/tbody>\r\n          <\/table>\r\n        <\/div>\r\n\r\n        <div class=\"pf-split\">\r\n          <div class=\"pf-box\">\r\n            <h3>Worked example<\/h3>\r\n            <p>\r\n              A penetration depth of <strong>12 mm<\/strong> with the <strong>\u00d8 2.5 mm Forest pin<\/strong> gives:\r\n            <\/p>\r\n            <p style=\"margin-top:10px;\">\r\n              <strong>Density = 700 \u2212 (18.5 \u00d7 12) = 478 kg\/m\u00b3<\/strong>\r\n            <\/p>\r\n            <p style=\"margin-top:10px;\">\r\n              That result is consistent with healthy softwood such as Norway spruce or Scots pine.\r\n            <\/p>\r\n          <\/div>\r\n          <div class=\"pf-box\">\r\n            <h3>Important note<\/h3>\r\n            <p>\r\n              These equations are generalised. Species-specific calibration improves accuracy, especially where precise comparison between species or structural interpretation is required.\r\n            <\/p>\r\n          <\/div>\r\n        <\/div>\r\n      <\/div>\r\n    <\/section>\r\n\r\n    <!-- 3 -->\r\n    <section class=\"pf-section\" id=\"density-classes\">\r\n      <div class=\"pf-surface\">\r\n        <p class=\"pf-kicker\">3. Practical interpretation<\/p>\r\n        <h2 class=\"pf-h2\">Indicative density classes for the \u00d8 2.5 mm Forest pin<\/h2>\r\n\r\n        <p class=\"pf-lead\">\r\n          For standing trees measured at breast height, the following indicative classes can help users interpret WOODPECKER readings.\r\n          These are screening values and should be used as guidance rather than as absolute acceptance criteria.\r\n        <\/p>\r\n\r\n        <div class=\"pf-table-wrap\">\r\n          <table class=\"pf-table\" aria-label=\"Indicative density classes\">\r\n            <thead>\r\n              <tr>\r\n                <th>Penetration depth<\/th>\r\n                <th>Estimated density<\/th>\r\n                <th>Density class<\/th>\r\n                <th>Typical indication<\/th>\r\n              <\/tr>\r\n            <\/thead>\r\n            <tbody>\r\n              <tr>\r\n                <td><strong>&lt; 8 mm<\/strong><\/td>\r\n                <td><strong>&gt; 552 kg\/m\u00b3<\/strong><\/td>\r\n                <td>HIGH<\/td>\r\n                <td>Dense, high-quality wood, often associated with hardwood or very dense timber<\/td>\r\n              <\/tr>\r\n              <tr>\r\n                <td><strong>8\u201314 mm<\/strong><\/td>\r\n                <td><strong>441\u2013552 kg\/m\u00b3<\/strong><\/td>\r\n                <td>MEDIUM-HIGH<\/td>\r\n                <td>Normal healthy softwood or lighter hardwood<\/td>\r\n              <\/tr>\r\n              <tr>\r\n                <td><strong>14\u201322 mm<\/strong><\/td>\r\n                <td><strong>293\u2013441 kg\/m\u00b3<\/strong><\/td>\r\n                <td>MEDIUM-LOW<\/td>\r\n                <td>Reduced density, possible juvenile wood, moisture effect, or early degradation<\/td>\r\n              <\/tr>\r\n              <tr>\r\n                <td><strong>&gt; 22 mm<\/strong><\/td>\r\n                <td><strong>&lt; 293 kg\/m\u00b3<\/strong><\/td>\r\n                <td>LOW \/ DECAY<\/td>\r\n                <td>Likely decay or severe wood degradation, further investigation recommended<\/td>\r\n              <\/tr>\r\n            <\/tbody>\r\n          <\/table>\r\n        <\/div>\r\n\r\n        <div class=\"pf-callout\">\r\n          <p style=\"margin:0; color: var(--pf-muted); font-size: 14.8px;\">\r\n            A high penetration depth does not automatically mean structural failure, but it is a clear signal that the reading should be assessed in context, together with species, moisture condition, age, and the purpose of the evaluation.\r\n          <\/p>\r\n        <\/div>\r\n      <\/div>\r\n    <\/section>\r\n\r\n    <!-- 4 -->\r\n    <section class=\"pf-section\" id=\"species\">\r\n      <div class=\"pf-surface\">\r\n        <p class=\"pf-kicker\">4. Species-specific reference values<\/p>\r\n        <h2 class=\"pf-h2\">Why wood species matters<\/h2>\r\n\r\n        <p class=\"pf-lead\">\r\n          Species-specific references improve the interpretation of WOODPECKER results. The same penetration depth can represent different density levels depending on the wood type and growth conditions.\r\n        <\/p>\r\n\r\n        <div class=\"pf-table-wrap\">\r\n          <table class=\"pf-table\" aria-label=\"Species specific values\">\r\n            <thead>\r\n              <tr>\r\n                <th>Species<\/th>\r\n                <th>Basic density<\/th>\r\n                <th>Typical \u00d8 2.5 mm penetration<\/th>\r\n                <th>Typical context<\/th>\r\n              <\/tr>\r\n            <\/thead>\r\n            <tbody>\r\n              <tr>\r\n                <td>Norway Spruce<\/td>\r\n                <td>400\u2013470 kg\/m\u00b3<\/td>\r\n                <td>10\u201316 mm<\/td>\r\n                <td>Forest \/ structural<\/td>\r\n              <\/tr>\r\n              <tr>\r\n                <td>Scots Pine<\/td>\r\n                <td>480\u2013540 kg\/m\u00b3<\/td>\r\n                <td>9\u201314 mm<\/td>\r\n                <td>Forest \/ plantation<\/td>\r\n              <\/tr>\r\n              <tr>\r\n                <td>Radiata Pine<\/td>\r\n                <td>420\u2013510 kg\/m\u00b3<\/td>\r\n                <td>10\u201315 mm<\/td>\r\n                <td>Plantation \/ breeding<\/td>\r\n              <\/tr>\r\n              <tr>\r\n                <td>Douglas Fir<\/td>\r\n                <td>450\u2013530 kg\/m\u00b3<\/td>\r\n                <td>9\u201314 mm<\/td>\r\n                <td>Structural timber<\/td>\r\n              <\/tr>\r\n              <tr>\r\n                <td>European Beech<\/td>\r\n                <td>680\u2013750 kg\/m\u00b3<\/td>\r\n                <td>6\u201310 mm<\/td>\r\n                <td>Structural hardwood<\/td>\r\n              <\/tr>\r\n              <tr>\r\n                <td>Pedunculate Oak<\/td>\r\n                <td>650\u2013720 kg\/m\u00b3<\/td>\r\n                <td>6\u201310 mm<\/td>\r\n                <td>Foundation piles<\/td>\r\n              <\/tr>\r\n              <tr>\r\n                <td>Black Alder<\/td>\r\n                <td>450\u2013530 kg\/m\u00b3<\/td>\r\n                <td>9\u201314 mm<\/td>\r\n                <td>Foundation piles<\/td>\r\n              <\/tr>\r\n              <tr>\r\n                <td>Eucalyptus spp.<\/td>\r\n                <td>500\u2013900 kg\/m\u00b3<\/td>\r\n                <td>5\u201315 mm<\/td>\r\n                <td>Tropical plantation<\/td>\r\n              <\/tr>\r\n            <\/tbody>\r\n          <\/table>\r\n        <\/div>\r\n\r\n        <div class=\"pf-callout\">\r\n          <p style=\"margin:0; color: var(--pf-muted); font-size: 14.8px;\">\r\n            For oak and beech, relatively low penetration values are normal because these species are naturally denser.\r\n            For spruce or radiata pine, the same low reading would indicate unusually dense material.\r\n          <\/p>\r\n        <\/div>\r\n      <\/div>\r\n    <\/section>\r\n\r\n    <!-- 5 -->\r\n    <section class=\"pf-section\" id=\"best-practice\">\r\n      <div class=\"pf-surface\">\r\n        <p class=\"pf-kicker\">5. Measurement quality<\/p>\r\n        <h2 class=\"pf-h2\">Key factors that affect WOODPECKER readings<\/h2>\r\n\r\n        <div class=\"pf-grid\">\r\n          <div class=\"pf-card\">\r\n            <div class=\"pf-icon\">MC<\/div>\r\n            <h3>Moisture content<\/h3>\r\n            <p>\r\n              Wet wood tends to allow deeper penetration, which can lead to underestimation of density. Compare measurements under similar moisture conditions whenever possible.\r\n            <\/p>\r\n          <\/div>\r\n          <div class=\"pf-card\">\r\n            <div class=\"pf-icon\">BK<\/div>\r\n            <h3>Bark presence<\/h3>\r\n            <p>\r\n              Measuring through bark inflates the penetration depth. For forest applications, measurements should be taken under the bark for more reliable comparison.\r\n            <\/p>\r\n          <\/div>\r\n          <div class=\"pf-card\">\r\n            <div class=\"pf-icon\">HT<\/div>\r\n            <h3>Measurement height<\/h3>\r\n            <p>\r\n              Standardising the test location at breast height, typically 1.3 m above ground, improves consistency across trees and sites.\r\n            <\/p>\r\n          <\/div>\r\n          <div class=\"pf-card\">\r\n            <div class=\"pf-icon\">AVG<\/div>\r\n            <h3>Number of shots<\/h3>\r\n            <p>\r\n              A minimum of three measurements at the same cross-section should be averaged to reduce local variation caused by knots, resin pockets, or grain irregularities.\r\n            <\/p>\r\n          <\/div>\r\n          <div class=\"pf-card\">\r\n            <div class=\"pf-icon\">AGE<\/div>\r\n            <h3>Tree age<\/h3>\r\n            <p>\r\n              Correlations between penetration depth and density are generally weaker in very young trees. The method performs best on plantation or mature timber.\r\n            <\/p>\r\n          <\/div>\r\n          <div class=\"pf-card\">\r\n            <div class=\"pf-icon\">CAL<\/div>\r\n            <h3>Pin wear and calibration<\/h3>\r\n            <p>\r\n              A worn pin or an out-of-calibration device can systematically bias the result. Regular inspection and annual recalibration are therefore essential.\r\n            <\/p>\r\n          <\/div>\r\n        <\/div>\r\n      <\/div>\r\n    <\/section>\r\n\r\n    <!-- 6 -->\r\n    <section class=\"pf-section\" id=\"limitations\">\r\n      <div class=\"pf-surface\">\r\n        <p class=\"pf-kicker\">6. Limitations<\/p>\r\n        <h2 class=\"pf-h2\">Useful for screening, not a substitute for engineering verification<\/h2>\r\n\r\n        <p class=\"pf-lead\">\r\n          WOODPECKER-based density estimates are indicative only. They are valuable for ranking, screening, trend monitoring, plantation management, and first-level condition assessment, but they are not a replacement for laboratory testing or full structural verification.\r\n        <\/p>\r\n\r\n        <div class=\"pf-split\">\r\n          <div class=\"pf-box\">\r\n            <h3>Suitable for<\/h3>\r\n            <ul class=\"pf-list\">\r\n              <li>comparing trees or timber elements within one project<\/li>\r\n              <li>detecting low-density zones or suspicious areas<\/li>\r\n              <li>forest improvement and plantation selection<\/li>\r\n              <li>indicative screening for timber condition<\/li>\r\n            <\/ul>\r\n          <\/div>\r\n          <div class=\"pf-box\">\r\n            <h3>Not sufficient on its own for<\/h3>\r\n            <ul class=\"pf-list\">\r\n              <li>final structural design values<\/li>\r\n              <li>formal load-bearing acceptance<\/li>\r\n              <li>laboratory-equivalent density determination<\/li>\r\n              <li>standalone assessment of timber safety in critical structures<\/li>\r\n            <\/ul>\r\n          <\/div>\r\n        <\/div>\r\n\r\n        <div class=\"pf-callout\">\r\n          <p style=\"margin:0; color: var(--pf-muted); font-size: 14.8px;\">\r\n            For load-bearing applications such as timber structures, bridges, or wooden foundation piles, assessment should always be carried out by a qualified engineer and in accordance with the relevant standards and guidelines.\r\n          <\/p>\r\n        <\/div>\r\n      <\/div>\r\n    <\/section>\r\n\r\n    <!-- 7 -->\r\n    <section class=\"pf-section\" id=\"literature\">\r\n      <div class=\"pf-surface\">\r\n        <p class=\"pf-kicker\">7. Literature basis<\/p>\r\n        <h2 class=\"pf-h2\">Published references behind the conversion approach<\/h2>\r\n\r\n        <p class=\"pf-lead\">\r\n          The interpretation method used here is based on published work around Pilodyn-type instruments and on the WOODPECKER manual context. These references support the use of penetration depth as an indicative measure for wood density and wood condition.\r\n        <\/p>\r\n\r\n        <ul class=\"pf-list\">\r\n          <li>Hansen (2000) on Pilodyn use in forest tree improvement<\/li>\r\n          <li>Cown (1978) on rapid density assessment in living trees<\/li>\r\n          <li>Wu et al. (2010) on Eucalyptus clones and wood property prediction<\/li>\r\n          <li>Later structural timber studies on density estimation in existing timber<\/li>\r\n          <li>Profound WOODPECKER manual and calibration context<\/li>\r\n        <\/ul>\r\n\r\n        <div class=\"pf-callout\">\r\n          <p style=\"margin:0; color: var(--pf-muted); font-size: 14.8px;\">\r\n            In practice, the best results are obtained when WOODPECKER measurements are treated as part of a broader assessment strategy, combining field method consistency, species knowledge, and engineering judgement.\r\n          <\/p>\r\n        <\/div>\r\n      <\/div>\r\n    <\/section>\r\n\r\n    <!-- CONCLUSION -->\r\n    <section class=\"pf-section\" id=\"conclusion\">\r\n      <div class=\"pf-surface\">\r\n        <p class=\"pf-kicker\">Schlussfolgerung<\/p>\r\n        <h2 class=\"pf-h2\">Schlussfolgerung<\/h2>\r\n\r\n        <p class=\"pf-lead\">\r\n          WOODPECKER measurements can be translated into meaningful technical information when they are interpreted correctly.\r\n          Penetration depth is not just a number in millimetres. With the right regression approach, species context, and measurement discipline,\r\n          it becomes a practical indicator for wood density and wood condition.\r\n        <\/p>\r\n\r\n        <ul class=\"pf-list\">\r\n          <li>lower penetration usually means denser wood<\/li>\r\n          <li>general equations can provide useful indicative density estimates<\/li>\r\n          <li>species-specific interpretation improves reliability<\/li>\r\n          <li>moisture, bark, shot averaging, and calibration strongly influence results<\/li>\r\n          <li>the method is highly useful for screening, but not a standalone structural proof method<\/li>\r\n        <\/ul>\r\n\r\n        <div class=\"pf-callout\">\r\n          <p style=\"margin:0 0 10px 0; color: var(--pf-muted); font-size: 14.8px;\">\r\n            <strong>Need reliable interpretation of WOODPECKER readings?<\/strong>\r\n          <\/p>\r\n          <p style=\"margin:0; color: var(--pf-muted); font-size: 14.8px;\">\r\n            The best outcomes are achieved when measurements are performed consistently, averaged correctly, and interpreted in the context of species, moisture, intended use, and applicable standards.\r\n          <\/p>\r\n        <\/div>\r\n      <\/div>\r\n    <\/section>\r\n\r\n    <!-- CTA -->\r\n    <section class=\"pf-section\" id=\"contact\">\r\n      <div class=\"pf-cta\">\r\n        <div>\r\n          <h3>Want to interpret WOODPECKER measurements with more confidence?<\/h3>\r\n          <p>\r\n            We support users with practical guidance on measurement consistency, field interpretation, and the technical background behind penetration-depth based density estimation.\r\n          <\/p>\r\n        <\/div>\r\n\r\n        <div class=\"pf-actions\">\r\n          <a class=\"pf-btn pf-btn-primary\" href=\"\/de\/contact\/\">Contact us<\/a>\r\n          <a class=\"pf-btn pf-btn-secondary\" href=\"#conversion\">View conversion method<\/a>\r\n        <\/div>\r\n      <\/div>\r\n    <\/section>\r\n\r\n  <\/div>\r\n<\/div>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>","protected":false},"excerpt":{"rendered":"<p>Interpreting WOODPECKER Measurements How to estimate wood density from mm readings and what influences the result The WOODPECKER is used to assess wood condition by measuring penetration depth at a fixed impact energy. In practice, users often ask the same question: how do you interpret a reading in millimetres, and can that value be linked [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":63,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"inline_featured_image":false,"page_builder":"","footnotes":""},"categories":[19],"tags":[],"class_list":["post-2395","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog"],"_links":{"self":[{"href":"https:\/\/profound.nl\/de\/wp-json\/wp\/v2\/posts\/2395","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/profound.nl\/de\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/profound.nl\/de\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/profound.nl\/de\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/profound.nl\/de\/wp-json\/wp\/v2\/comments?post=2395"}],"version-history":[{"count":6,"href":"https:\/\/profound.nl\/de\/wp-json\/wp\/v2\/posts\/2395\/revisions"}],"predecessor-version":[{"id":2401,"href":"https:\/\/profound.nl\/de\/wp-json\/wp\/v2\/posts\/2395\/revisions\/2401"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/profound.nl\/de\/wp-json\/wp\/v2\/media\/63"}],"wp:attachment":[{"href":"https:\/\/profound.nl\/de\/wp-json\/wp\/v2\/media?parent=2395"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/profound.nl\/de\/wp-json\/wp\/v2\/categories?post=2395"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/profound.nl\/de\/wp-json\/wp\/v2\/tags?post=2395"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}