chard wood and soft shelled eggs

[snowflake]

Hi! a while ago I was having trouble with soft shelled eggs from one of my hens. oyster shell always available I found some chard wood and put it in the run near the oyster shell, Have not had a soft shell since.

 

[elizabethlongwood]

Chard wood, pardon my ignorance, but what is that. The woody stems of swiss chard??