Mycorrhizae

Wild Ones member Janet Carlson asked, “Is there a way to increase the fungi in the soil? I’ve been working on a yard heavily infested with buckthorn. Nothing grows in some parts. Now garlic mustard is moving in after buckthorn removal.”

I responded with, “I found a good source from the Smiling Gardener: 9 Ways To Help The Beneficial Fungi In Your Soil for you. You can buy mycorrhizae at places such as Ace or Amazon. A good resource of mycorrhizae is Mycorrhizal Applications.

P.S. Do you have the ability to use a cover/nurse crop like oats, beans, and clover?”

Mycorrhiza

A mycorrhiza is a symbiotic association between a green plant and a fungus. A fungus which grows in association with the roots of a plant. The plant makes organic molecules such as sugars by photosynthesis and supplies them to the fungus, and the fungus supplies to the water and mineral nutrients taken from the soil.

Nine Ways to Help the Beneficial Fungi in Your Soil

Phil Nauta wrote, “Mycorrhizal fungi live in the soil in partnership with plants. The beneficial effects of these fungi are that they:

• Seek out phosphate and other nutrients and then bring them to plants.
• Connect many plants together, allowing for nutrient exchange between plants.
• Supply water to plants.
• Protect plants from fungal diseases and other root-feeding microorganisms.
• Improve soil structure, so it’s less compacted, with more spaces for air and water.”

Happy Soil Fungi

Mycorrhizal inoculant is a powder that adheres to the roots of plants. Some ways you can keep the soil’s beneficial fungi happy:

1. Phosphorus fertilizer. Fresh manure can oversupply phosphorus. Don’t use too much, especially chemical insoluble phosphorus. Rock phosphate is insoluble. It needs to be worked on by microbes.

2. Other fertilizer. Other than phosphorus, overfertilizing can inhibit micorrhizal fungi, so be sure to just fertilize a little at a time. You can use gypsum or potassium sulfate – which is much more soluble – and will be less damaging to the fungi.

3. Organic fertilizer. Small amounts of many different nutrients (such as rock dust or ocean water) won’t oversupply any one nutrient.

4. Pesticides. Fungicides kill fungi. Herbicides, insecticides, and other pesticides can too.

5. Mulch. Mulch leaves and straw will provide protection and habitat for the fungi. We don’t like to use wood chips. They encourage fungi, but I will use them around trees and shrubs.

6. Diversity. Mycorrhizal fungi benefit from having other microbes around. Compost does not provide the fungi itself, but it does support them. A ground cover or cover crop is useful for plants to partner with.

7. Water. Fungi need water and air. We want roots and fungi to spread out and go down. If your soil is too wet,  the fungi will suffer. We need to let the soil dry out between waterings.

8. Tilling. Do not till, plow, or double dig. That will slice your microbes into pieces.

9. Other soil disturbance. Topsoil removal and compaction/erosion is devastating to fungi.

Mycorrhizal Animation

To which Janet wrote, “Thanks. Great information. I think we can plant clover there since we don’t plan to plant this year.”

Read about Under the Covers: Nursing Clovers to Maturity  and  Cover Crops Factsheet.

The graphic is by Charlotte Roy courtesy of Wikimedia.