We just bought our house less than a month ago and outside there are several patches of this plant including this one in the flower bed in the front. It filled it up pretty thick and I have other perennials I want to plant in it so I'm slowly removing them. I'm trying to save some of them so I can replant them elsewhere. The neighbors said they hadn't seen flowers on them so I don't think they are daffodils or tulips since they would've already been in bloom. What the heck are they? As you can see, they have bulbs so I'm assuming they were planted intentionally. They have been growing without anybody caring for them for a while so I know they are tough. I just hope they will have flowers eventually but I'm not sure. Thanks to everybody for their replies. I just signed up to this site yesterday and it's already been such a hugh help.
Common name is Day lily. We have them growing wild here on the east coast of Canada, I have orange ones in my garden, and I especially planted them in the rough areas in my back field where I can't get my lawn tractor in. If you don't want them make sure you dig every bit up, because they'll return if one little bit remains. There ae so many different colors, wait and see what color they are before you dig them out, if that's your plan, that is if it's not to late already, they should bloom by Late june.