What are these plants?
#1 - looks like a milkweed but not sure. Grows only in shady area of garden. Seems to spread through rhizomes. Haven't seen flowers. #2 - looks like an Arisaema. Has the right kind of flower. Leaves are single, big hearted shaped on a stem - not the trilobe of Arisaema. There are also multiple leaves per plant. Has a bulb that is fairly deep, maybe 8-10". Has spread throughout the yard.
Photo #1 is not milkweed. It's possible it is suckering from a shrub. Please send photos when, or if, it produces flowers. You could also send a photo of the roots or rhizomes.
Photos #2 & 3: Italian arumhttp://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=y760 This is an aggressive spreader and we recommend that you not let the berries ripen. It is on the list of foreign invasive plants of Maryland. You may want to remove it, if you want a natural woodland garden, or if there is any possibility of it escaping to park or natural areas near you.
Thanks. #1 is not suckering from a shrub. I will have to do more investigation on it.
This looks like Dogbane, possibly Apocynum cannabinum or Apocynum androsaemifolium. They do get spreading roots like this.