Grow Bag Fungi - help!

[bradlo]

Hi folks...
Very new to this gardening lark!!!
I have noticed several of these Fungi (?) in my tomato grow bags...
Any idea what it might be, and is it harmful ?
Many thanks

[Urban]

I had a few of those fungi growing on the newspaper pots that I started off all my plants in February
They dissapeared after a few weeks, and my plants are still all going strong

Next year I think I'll give my newspaper a quick blast in the micro before I make pots though

[rustylady]

There looks to be a lot of woody stuff in the compost, so I suspect this is encouraging the fungi. Just pick them off, they won't harm your plants.