Fungi – Keeping It In Check

Q: I’m clearing out a pine island that was filled with junipers under the pine trees. I’m finding a white, gauzy, fungus-looking substance under the pine straw. What is it and how diligent do I need to be in removing the stuff?

A: Knowing how unfriendly the sharp, stiff needles of a juniper can be, I’ll bet you have not renewed the mulch under them for several years. As the pine straw decomposed over that time, various fungi colonized it. The white stuff is just the mycelia (the “roots”) of the fungi feeding on your pine straw. I have seen cases where the mycelia became so thick that water could not penetrate it and nearby plants suffered from dry soil. That’s why it is a good idea to rake out the mulch under shrubs every two years. The fungal mat will be destroyed and the fresh mulch will look better besides. As long as you break it up thoroughly, it will not harm plants that replace the junipers.