I have a huge number of volunteer pumpkins that grew from the compost pile. While I know that they may not be the variety they grew from due to cross pollination, I heard someone mention they could be poisonous? It doesn't even make sense to me, but I thought I would at least ask. Only reference I found to poisonous pumpkins in an online search was a study published by OHSU, et al and they seemed to imply that bitter squash could cause GI issues and perhaps the risk was higher in non-hybrid or wild squash. http://www.ohsu.edu/emergency/about/news/2012/nacct/posters/squash.pdf I would welcome your response and expertise.
Lane County Oregon fruits and vegetables
Pumpkins, squash, and cucumbers sometime cross pollinate with neighboring plants. The fruit produced by these hybrids may not be desirable or even edible. They will NOT be poisonous. If you like unpredictability, however, you may want to leave the squash to grow. If you want something to eat, i suggest planting a known variety.