Grease and flour one 9 x 5" and two 3 x 5" mini loaf pans. Line the bottom of the pans with parchment paper. Preheat oven to 300 F.
In a large bowl, cream together butter and sugar. Add eggs, one at a time, beating after each one. In a small bowl, mix salt, baking soda and flour; add to creamed mixture alternatively with buttermilk. Add lemon zest and pecans, stirring by hand.
Spread batter in prepared pans. Bake small loaves for 45 minutes and large loaf for 1 hr. 20 minutes. Cool loaves in the pan for 10 minutes before removing to wax paper covered rack. Glaze while still warm.
Glaze: Mix 1 cup powdered sugar and 1/2 cup lemon juice. Poke holes in bread with toothpick and drizzle glaze slowly over bread using about half of the thin glaze. To the remaining glaze, add another cup of powdered sugar to get a thicker glaze. Spread this additional glaze over the breads. Cool completely.