entire heads of lettuce wilted

[Susa]

I have the same problem every night or so. The lettuce heads are all standing erect and strong, then, the next morning, one or two are completely wilted and flopped over. I don't see anything except that some of the leaves seem to be severed at the base of the head. Is this an insect? I never see any bugs around the beds, so I'm confused. I have seen green june beetle grubs, but only in my potato bed, not the lettuce.
Thanks

[PunkRotten]

This happened once with some Kale I had. I do think it is an insect some type of caterpillar. Not sure though.

[DoubleDogFarm]

Yes, Most likely some grub / cut worm has or is eating the root system.

I would lift one of the plants with a garden fork.

Eric

[applestar]

How big are these lettuce? I think cutworm is most likely as well if the lettuce are just laying there and not eaten. Try toothpicks stuck in ground on either side (2 opposite sides) close to stems.

[Susa]

I googled cutworms and it sure does sound like they are the culprit. Thanks! This forum is awesome.
The lettuce range from 5'-7' in height.