The image above shows a cross-section of timber taken approximately 15m below the highest rigging point in a Eucalyptus globulus that into trees climbers recently dismantled. The tree ‘felt wrong’ and the plan was adjusted: smaller pieces and as much cut-and-drop as possible.
Having a look at the timber when the job was finished showed that you need to trust your instincts. The heartwood was powder that you could crumble in your hand. The image on the right shows the decay marked in purple to make the extent easier to see.