1 annual ring 3 false growth ring 4 resin ducts 2 growth rings
English name: Pine Scientific name: Pinus sp. Familia: Pinaceae Classis: Coniferopsida Phylum: Gymnospermae Regnum: Plantae
Annual rings in this cross-section of the stem appear clearly because of the difference in “density” between spring wood and summer wood. Spring wood has a lighter color than summer wood since tracheids formed in spring have a large diameter (seen radially) and a thinner cell wall. The formation of cells with a larger lumen (opening) and a thinner cell wall is an adaptation that enables sufficient supply of water for the tree. (Remark: the cell wall in this specimen have been stained with a red dye to emphasize contrast. However, also unstained material shows a distinct transition between spring and summer wood). View a detail of a cross-section
