Q&A: Can You Identify Mystery Weblike Substance?

Reader Christina shares some photos of a white web like substance appearing in her terrarium. I am not familiar with this particular affliction but I share in hopes that someone else might have experience with this fungus or insect problem.  The best course of action for a mystery fungus is removal of the afflicted areas.  If the problem persists, you may need to empty out your terrarium and try building it again with new plants and soil.

Christina says "I've been noticing a strange white almost weblike thing growing on the branch points of some of my plants. The plants seem to be growing well but I was just wondering if you would happen to know what it is and how I can fix it. I've just been trimming it off hoping it goes away. I haven't had any problems with bugs in it so I don't think it's a nest of any kind. I've attached some pictures of the 2 plants that seem to be affected. My terrarium has quite a large opening at the top that I never cover and it gets a good amount of sunlight."