Jacket Plum Dieback Monitoring Project (Eastern Cape)

Overview

The Jacket Plum or Pruimboom (Pappea capensis) is a widespread and often long-lived tree species in the Eastern Cape. In recent years, increasing numbers of these trees have been observed showing signs of severe dieback or mortality.

This project aims to document the extent and severity of this dieback across the landscape using a simple, rapid, and scalable observation approach.

View and contribute to the project here: https://www.inaturalist.org/projects/jacket-plum-pruimboom-health-monitoring-network-eastern-cape

Why this project matters

The Eastern Cape experienced a prolonged drought between 2016 and 2022. Since then, widespread dieback in Pappea capensis has been observed in multiple areas.

These trees are often centuries old, and there is currently little evidence of successful recruitment of seedlings and saplings into adult populations. This raises concerns about the long-term persistence of the species in parts of its range.

At present:

• Observations of dieback are largely anecdotal

• There is no coordinated, landscape-scale dataset

• The causes and extent of mortality remain unclear

This project provides a way to systematically record these patterns across the region.

Project approach

The project is built using iNaturalist, allowing anyone to contribute observations using a smartphone.

Each observation captures:

• A focal tree (Pappea capensis)

• A rapid count of nearby individuals (of P. capensis), classified as:

  • Good

  • Showing dieback

  • Dead

Importantly, this approach focuses on proportions rather than fixed-area sampling. Observations are based on what is visible from a single point, allowing rapid data collection across many locations.

How to contribute

1. Locate a Pappea capensis tree

   • Preferably one showing dieback or mortality

   • If none are present, a healthy tree can also be recorded

2. Take photos:

   • Whole tree

   • Close-up of leaves or branches

   • Surrounding area (if possible)

   • For dead trees: bark condition (e.g. peeling bark)

3. Count nearby individuals:

   • Include all visible Pappea capensis trees you can confidently identify

   • Classify each as:

     • Good (full canopy, no visible stress)

     • Dieback (partial canopy loss or decline)

     • Dead (no leaves or clearly non-functional)

4. Upload the observation via iNaturalist and complete the project fields

Important notes for contributors

• Only include trees you can confidently identify as Pappea capensis

• Exclude distant or uncertain individuals

• Count each tree once

• Multi-stemmed trees with a single canopy should be counted as one individual

• Include the focal tree in your counts

• If unsure, it is better to leave a tree out than to guess

What will the data be used for?

The data collected through this project will be used to:

• Map the spatial extent of dieback and mortality

• Quantify the proportion of affected trees across landscapes

• Identify hotspots of severe decline

• Support research into drought impacts on long-lived woody species

In the longer term, the dataset will contribute to scientific analyses and publications on drought-driven vegetation change in the Eastern Cape.

Relevance for restoration and carbon projects

Understanding tree mortality at a landscape scale is critical for interpreting changes in ecosystem structure and carbon storage.

This dataset may help:

• Provide context for mortality observed in monitoring plots

• Distinguish between local project effects and broader environmental drivers

• Inform restoration strategies under increasing climate variability

Get involved

This project is open to:

• Researchers

• Students

• Landowners

• Citizen scientists

Even a small number of observations can contribute to a much larger understanding of landscape-scale change.

Join the project here:
https://www.inaturalist.org/projects/jacket-plum-pruimboom-health-monitoring-network-eastern-cape

Project team and contact

For more information or collaboration opportunities:

Prof. Alastair Potts