Suppose you want to make a salad, but when you open the fridge you see that the lettuce you need is stained with red color on the bottom.
Although it may appear vile, it is not necessary to discard the entire head. Relax, because this is a simple problem to solve.
In reality, the reason is quite elementary. Most chefs would call the red gunk that develops on your lettuce near the root rust.
Your "rusty lettuce" is the result of an overabundance of moisture during storage. The good news is that it appears worse than it is.
Yes, the lettuce is still edible, so there is no reason to throw it away. Although it may appear undesirable, the situation is easily salvaged.
You need only use a chef's knife to remove the rusty red spots. You'll get lettuce that appears fresh in no time!
Always keep the lettuce stable and cut away from you to avoid any accidental stab wounds.