What poison to use to kill oleanders shrubs?

To kill oleander shrubs, glyphosate is an effective herbicide that can be used, as it targets a broad range of plants. It's important to apply it carefully to avoid damaging surrounding vegetation since glyphosate is non-selective. Always follow the manufacturer's instructions for application and safety precautions. Additionally, consider alternative methods such as cutting the plants and applying the herbicide directly to the cut stumps to minimize environmental impact.