Measurements taken in 1940 on 118 common black walnut seedlings planted in 1939 showed 9/16" average diameter of seedling at crown, 5/16" average diameter of pith at crown; 3/8" average diameter of seedling at top; and 1/4" average diameter of pith at top; 3.26 inches average length of solid pith above crown; 2.91 inches average length of solid pith in root below crown. =Pith:= Pith in the black walnut is chambered (lamellate) in the older wood, but solid in the younger, growing wood. The plates are a light brown color, getting larger in diameter toward the top of the year's growth. The leaf traces from the leaf rachis to the pith show heavier from the bottom buds of the branch than at the tip, and the pith is usually solid at the bottom of the branch. =Roots:= When the nut of the black walnut germinates in the soil the lobes or cotyledons do not rise above the ground like the cotyledons of the bean but remain in the nut shell under ground, and are broken off in the growth of the seedling, the root going down and the stem rising above the ground. Where the cotyledons are broken off, the so-called crown of the walnut, two rough places appear, nearly opposite on the stem. In these rough places, two groups of buds are formed, rarely three groups. Cytological studies at Iowa State College have not shown why there are not stem initials in the tap roots of the walnut. When the root is cut off a foot underground, root initials develop but no stem initials. The sensitivity of walnut leaf buds to water may have something to do with it. =Buds:= Buds of the walnut are in vertical groups of two or three in the axils of the leaves. They have few scales. They appear on seedlings and current year branches. Some have short stalks. If broken off they do not usually grow back again. The second year, these buds usually drop off in mid-season. In cutting off buds, unless the group of buds is taken out as a chip, some may grow out again. =Leaf arrangement:= There is a three rank arrangement of leaves in the walnut, the ninth leaf coming in the same position as the first. According to the work of Caesalpino, the buds should then rise in three places at the crown. Only in rare cases does this occur in the black walnut, although it is usual with the Persian walnut. If the nut is planted deep this causes much suckering and a tendency to etiolate the buds so they will stand water. =Buds are sensitive:= Buds are sensitive to water, and storage material must be fairly dry and cool. In two large boxes of scions received last year from Germany, some 20 varieties of Persian walnut, all had dead buds when received. They were packed in German peat. When buds are covered with wax the wax must not be too hot or it will kill the buds. In placing grafted walnuts in sphagnum or sand they should not stay wet or the buds will die. Either unions must be above damp sand or sphagnum, or the buds be protected by wax or adhesive.