Managing isopods in living soil can be beneficial for your soil ecosystem, as isopods play a key role in breaking down organic matter and cycling nutrients. However, if their population becomes too high, they might start feeding on plant roots or seedlings. Here are some strategies for managing isopods in living soil:

1. **Balance Organic Matter**
- **Add organic matter judiciously**: Isopods thrive on decaying organic material. Ensure you are not adding too much organic matter at once, which can lead to population explosions.
- **Use well-composted materials**: Compost that has broken down thoroughly is less attractive to isopods than fresh organic matter.

2. **Monitor Moisture Levels**
- **Maintain appropriate moisture**: Isopods prefer moist environments. Ensure your soil is well-drained and not overly wet.
- **Avoid overwatering**: Excessive moisture can lead to high isopod populations.

3. **Introduce Natural Predators**
- **Encourage beneficial insects**: Predators like beetles, spiders, and centipedes can help control isopod populations.
- **Birds and small mammals**: If feasible, allowing birds and small mammals access to your garden can help keep isopod numbers in check.

4. **Use Physical Barriers**
- **Row covers and collars**: Protect vulnerable seedlings by using physical barriers.
- **Mulch wisely**: Use mulch that is less attractive to isopods, such as coarse wood chips, and avoid piling mulch too close to plant stems.

5. **Traps and Baits**
- **Potato slices**: Place slices of potato on the soil surface overnight to attract isopods. In the morning, collect and remove the slices along with the attached isopods.
- **Rolls of wet cardboard**: Similar to potato slices, these can be used to attract and trap isopods.

6. **Soil Disturbance**
- **Tilling and turning**: Occasionally turning the soil can disrupt isopod habitats and reduce their populations. However, this should be done sparingly to maintain soil structure and health.

7. **Companion Planting and Plant Selection**
- **Plant resistant species**: Choose plants that are less susceptible to isopod damage.
- **Companion plants**: Some plants can deter isopods, although this approach may require some experimentation.

8. **Organic Sprays**
- **Neem oil or diatomaceous earth**: While these should be used cautiously, they can help reduce isopod populations if they become problematic.

9. **Integrated Pest Management (IPM)**
- **Regular monitoring**: Keep an eye on your isopod populations and plant health. Early detection can prevent large infestations.
- **Balanced ecosystem**: Aim for a balanced soil ecosystem with a diversity of organisms that keep each other in check.

Final Considerations
Remember, isopods are generally beneficial and contribute to the overall health of your living soil. Management should aim for balance rather than eradication. If you are seeing damage to plants, first ensure that isopods are indeed the culprits, as they are more often beneficial than harmful.