This is pretty normal from where I live. Actually everywhere that is not getting clean or cut weekly you will find them. I have not really experience how itchy it is, but I can see DH skin when he gets it. He scratch his skin until it start bleeding.
I do have some kind of detergent allergies in the palm of my hand and DH kept telling me that it looks like poison ivy. I get this itch and then when I scratch it long enough water will form inside. The same reason why I can never wash clothes by hands back home. I always wears gloves when I have to wash clothes.
If you see any of the above image in your woods stay away or spray it weed killer, that is only my suggestion. Or you can leave it alone your choice.
You can use calamine lotion to ease the itch or if you are tough enough leave it be. I actually use candle dripping on my hands when they itch, running hot water will do too and cool it with ice to prevent being inflame. Those are what I use, how about you?