Resistograph Testing for Tree Decay

Quantifiable evidence of structural wood integrity. We utilize the IML RESI-PD400 to map internal density, identify hidden cavities, and provide defensible safety data.

If your Local Authority, Tree Consultant, or Tree Surgeon has requested further in-depth information regarding the internal condition of your trees, Arbor Cultural can help. We have invested in the high-level diagnostic technology required to give you absolute certainty. We provide specialist Resistograph testing, courtesy of our state-of-the-art IML RESI-PD400 instrument. Sometimes, knowing what is happening inside a tree via visual inspection alone is impossible; a tree may appear structurally sound externally while harboring significant internal rot. Our mission is to provide the precision data needed to protect people, property, and your legal Duty of Care.

Leading-Edge Strength Measurement

Resistograph testing is a non-destructive way to analyse the resistance of wood to drilling and the amount of pushing force and rotating force needed to penetrate a tree stem. Different decay processes—such as white rot or brown rot—weaken wood in distinct ways. For instance, some fungi digest cellulose while others target lignin. This is why capturing both resistance and feed-force data is critical for a high-accuracy assessment. This sophisticated piece of kit accurately measures how much strength a tree’s stem or branch has (or hasn’t) lost by gauging the relative density of the timber at the microscopic level. For developers and homeowners, this provides the technical evidence required to satisfy Building Control and Local Councils, often facilitating planning approval that would otherwise be refused.

The Science of Wood Density Resistance

The core principle of the RESI-PD400 is the measurement of energy consumption. As the needle-thin drill penetrates the wood, the device records the torque required to maintain a constant speed. Variations in this torque correspond directly to the physical density of the wood fibers. A sharp drop in resistance indicates a cavity, while a gradual decline often signals active fungal degradation or soft rot. This high-fidelity data allows us to calculate the "R-factor" (residual strength), giving you a mathematical basis for tree management rather than relying on visual guesswork.

Protecting Your Landscape Assets

In our professional opinion, this represents arboricultural work at its most refined. By utilizing minimally invasive techniques, we help preserve both ancient specimens and modern landscape features, maintaining a green environment while ensuring total safety compliance. Knowing what is happening internally can avoid costly legal action and keep nearby property secure. As a member of the Consulting Arborist Society (CAS) and Bond Solon trained experts, Arbor Cultural Ltd provides the technical oversight needed to successfully discharge your planning conditions, satisfy insurers, and Finish the Build.