Doublethink and scale mismatch polarize policies for an invasive tree

Area of Science:

• Ecology
• Conservation Biology
• Environmental Policy

Background:

• Invasive species management policies can conflict with ecological knowledge, leading to negative societal outcomes.
• The density-impact invasive species curve is a scientific tool used to guide management strategies.
• Juniperus virginiana (Eastern redcedar) invasion is altering North American ecosystems, causing biodiversity loss, increased wildfire risk, and reduced grazing profitability.

Purpose of the Study:

• To evaluate the alignment of Juniperus virginiana management policies with the scientifically-based density-impact model.
• To identify policy-ecology mismatches in native invader management.
• To assess the potential of current policies to meet sustainability targets.

Main Methods:

• Land cover data were used to determine Juniperus virginiana invasion stages across three Nebraska ecoregions.
• The density-impact model was applied to define invasion stages at the land parcel level.
• Policy documents were analyzed for alignment with the density-impact model.

Main Results:

• Nearly all analyzed policies exhibited "doublethink" and mismatches with ecological understanding.
• Policies often promoted Juniperus virginiana spread while simultaneously managing it as a native invader within the same ecoregion.
• Management failures are likely due to a lack of prioritization for incipient invasion stages.

Conclusions:

• Effective invasive species management requires policies aligned with the specific invasion stage at local and ecoregion scales.
• A shift is needed from ideological classifications (native vs. non-native) towards a framework addressing unique native species invasions.
• Addressing anthropogenic drivers and ecosystem service impacts is essential for managing native invaders like Juniperus virginiana.