A young layer of wood located directly beneath the bark is sapwood (also called obolon, basal, and blonch). It is considered less resistant to damage by insects or fungi, and also has low strength and contains a lot of water, compared with the ripe inner part of the tree and the core. In nature, there are tree species whose wood consists entirely of sapwood, for example, aspen. A thick resinous mass is deposited in it - resin, which is mined by making cuts of the bark on conifers.
Wood structure
Wood has the following structure:
- Nucleus - is formed as a result of the death of living cells. It is dark in color.
- Sapwood is a layer through which nutrients and water flow from roots to leaves.
- Cambium is a thin layer composed of living cells. From it comes the annual growth of the tree in thickness.
- Bast layer - conducts organic matter produced in the leaves to the roots of the tree.
- The bark is a rough outer layer. It serves as a protection against various mechanical damages and weather conditions.
What is sapwood?
Sapwood is a layer of wood that lies immediately beneath the bark of a tree. On it is the flow of water from the root system into the leaves. The sapwood is lighter in color than the inside of the tree, called the core. It has less strength and resistance to fungal diseases and insects. It is known that:
- Some tree species, namely birch and aspen, are entirely composed of sapwood only.
- In oak, undercoat is not used due to its increased softness.
- The use of cherry sapwood is determined visually.
Pine trees immediately below the bark contain a very valuable resin called resin, which, when harvested, exposes the surface of the sapwood. In addition, from ancient times people used this layer of some young trees for food.
The core and sapwood of wood
Young trees of any species do not contain a kernel, they are completely composed of sapwood. Only with time does this wood enter the core as a result of blockage of the water supply paths, resins, calcium carbonate and tannins. Therefore, the color of the core becomes darker. In different trees, the time interval for the formation of the nucleus depends on the growing conditions and species. The transition from the subcortex to the nucleus is both smooth and sharp.
Fancy food
Obolon or sapwood is a young layer of wood. It can be used as food. During the famine, the inhabitants of Leningrad during the blockade ate the so-called "birch porridge", that is, the birch bark, and the northern peoples - spruce. Various methods of cooking:
- Pine, spruce finely cut and cook, while changing the water several times. This procedure is necessary to get rid of the resin. Then it is dried and added to milk, flour or eaten immediately.
- Chop the birch, fill it with water and wait until it swells. Then boil.
In addition, sapwood of larch, linden, and aspen is used as food. It is known that Kamchatka hunters, leaving for fishing, took only salmon caviar from food. On the way, they cut a birch sapwood and ate it instead of bread.
