Yes, forgoing periodic crop tree release treatments within hardwood plantations will frequently result in trees with smaller crowns. Small crowns produce skinny, small diameter trees. Skinny, small diameter trees produce low volume sawlogs compared to larger-crown, larger-diameter trees grown over the same time period on the same piece of land. The key to black walnut plantation thinning is to maintain an optimum number of appropriately sized trees growing throughout the rotation age of the stand.
Stunted black walnut plantations are an all too common occurrence throughout the Midwest? Why? Ironically, it's a woodland owners' fear and recalcitrance to periodical thin their pride and joy stand of black walnut trees that leads to unrealized financial gains in the form of small, skinny black walnut trees with limited sawlog and veneer potential.