My Brussel Sprouts had been doing really well, until two days ago. The day after I planted tomotoes and bell peppers, one of the sprout plants suddenly started to sag. I noticed while turning the soil with a spade that their was a critter tunnel about 5" under the surface where I panted tomotoes. This is about 10' away from the sprout plants. I'm wondering if maybe I drove a mole from one side of the garden to the other and it killed my plant on it's way. I don't see any signs of tunneling around it on the surface.

Take a look at the pic. What do you think the problem could be? The mole thing is probably unrelated. It's just the only thing I could come up with.

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