Q.All My Spreading Ostrich Ferns Had Perhaps Fungal Problems… How To Prevent
I have never had this problem before with them. It looked like something spreading from one plant to another
Certified GKH Gardening Expert
Unfortunately, your photo did not come through. I am unable to address the situation, properly.
I can suggest using fungicides. This will help prevent and combat fungal infections.
Here are some articles that will help:
https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm
https://www.gardeningknowhow.com/garden-how-to/info/homemade-fungicide.htm
https://www.gardeningknowhow.com/ornamental/foliage/ostrich-fern/growing-ostrich-ferns.htm