Toe jam

Where did the phrase "toe jams" come from? I know what it means.

If you know what toe jam means, I needn't tell you that it is the dirt that collects between your toes, and can develop an unpleasant odor. But some others may be curious.

The Oxford English Dictionary cites, as its earliest example, a quotation from 1934, by Roy Campbell, s South African poet who lived extensively in England, in a book of memoirs ("Broken Record").

Between toes? I understood "toe jam" as the dirt, plus sloughed-off skin cells and whatever else is there, that collects under the edges of toenails. Dirt between toes is easily washed off. That other stuff is more persistent. ~rb