There are often plants that appear in our yards and gardens that we didn’t intentionally plant, and happily, some of them are sources of food and medicine. My self-sown radium weed, Euphorbia peplus, comes up every autumn, and is at its best in late winter. It is helpful to eliminate the less dangerous skin cancers, using its burning white sap. I have used it several times on my arms and trunk. DISCLAIMER: This is not medical advice. Do your own research, use at your own risk, and consult with a well-informed medical practitioner.