Dry and crumbly fan leaves

I have a new plant thats about 25 days old its about 5 inches tall and is at its like 7th or so node. The bottom fan leaves feel very dry and will crumble and crack when i squeeze them between my fingers. Do I trim these off?

Out of curiosity, do have a fan blowing directly there, I have the same problem on a couple leaves of my plant and thought it might be from dry air constantly blowing.

I do not have a fan blowing directly at the plant at the moment. I was just wondering if you are supposed to cut off the whole leaf or just the dead portions of that leaf?

I have the same problem with the same age plants, I had a fan blowing directly on two of them, these are the only ones affected. Im gona flush and see what happens! any info appreciated!