Why do pine trees have two kinds of leaves? What do the leaves of a pine tree look like?

Leaf type two, i.e., spiny leaves and squamorous leaves; Thorny leaves are born on young trees, old trees are all scales, and mature trees have both thorny leaves and scale leaves; The scales and leaves of the one-fold branches born in annual branchlets are three-lobed whorls, straight and tight, nearly lanceolate, the apex slightly acute, millimeters long, and there are oval-shaped slightly concave glands near the middle of the dorsal surface; The thorny leaves are alternately whorled, obliquely spread, loose, lanceolate, apex acute, 6-12 mm long, slightly concave above, with two bands of white powder.

The leaves of the pine tree resemble pine needles. During the whole process of pine growth, its drought resistance is extremely strong, and due to the influence of its drought-resistant structure, this type of pine has narrow leaves and a more developed cuticle, and the leaf surface area and volume are relatively small.

In addition, the stomata usually sag, but they are relatively ideal in terms of tissue development, and from a physiological point of view, they are very cold and drought tolerant, so they will not be affected by water shortage.

Morphological characteristics

When the pine trees are young, the crown is pyramid-shaped, and the branches are mostly in the shape of a wheel. After the seedlings are unearthed from the cotyledons, the first leaves are primary, which are arranged in a solitary spiral shape, and the linear-lanceolate leaf margin is toothed.

The primary leaves perform the function of leaves for 1 to 3 years before the needles appear, usually in bunches, on the tips of short branches. There is a leaf sheath at the base of each bundle of needles, which falls off or stays in the early stage, and the position of the resin tract in the mesophyll tissue is relatively constant in adult plants, which can be divided into three types: ectophytic, mesophytic, and endophytic.

The leaves of the pine tree resemble pine needles.

The leaves of the pine tree resemble needles, also known as pine needles. Pine needles, the leaves of the pine tree, the leaves are like needles, so they are called. Pine is a plant of the family Pinaceae, Pinus.

Pine tree. This plant is a plant of the Pinaceae family, Pinus genus. There are many kinds of pine trees in the world, there are more than 80 species, and the species of pine trees are mainly divided into Masson pine, Pinus tabuliformis, whitebark pine, podocarpus, Huashan pine, Dabie Mountain five-needle pine, Korean pine, red pine, black pine, Huangshan pine, Yunnan pine, golden pine, sylvestris pine, cedar and so on.

It is widely distributed. For example, Pinus tabuliformis, Pinus sylvestris, Pinus sylvestris sylvestris and Pinus sylvestris sylvestris distributed in North China and Northwest China, Pinus massoniana, Pinus huangshanensis and Pinus alpine in Central China, Pinus bashanensis in Qinba Mountains, as well as Pinus taiwanensis and Pinus breviflora in North America, are the main tree species for afforestation in barren mountains in China. Pine trees are wheel-shaped branches, with long internodes, relatively thin and straight branches or slightly curved downwards, and slender needles in bundles.

Its canopy looks fluffy and not compact, and the word "pine" is a visual description of its canopy characteristics. Therefore, "pine" is a type of tree with a fluffy crown. Pine trees are sturdy and have a very long lifespan.

The leaves of the pine tree are distinct and dense, like fine green needles at the roots. It will bear fruit called pine cones.

Hello! The leaves of the pine tree resemble needles, and it has another name for pine needles.

Pine is one of the more common plants, and its leaves are not broad, flat leaves, but thin strip leaves.

So what do the leaves of such a pine tree look like, in fact, it is very similar to the needles in life, so its leaves are also called pine needles.

The pine needles of the pine leaves have good medicinal value, and the active ingredients in them can be extracted to dilate the arteries and blood vessels, and can promote blood circulation in the body, enhance people's body immunity, and make people's bodies become healthier and stronger.

The pine tree is like a majestic sentinel, like a green tower, protecting us.

1. The leaves of the pine tree are like dancing dancers, dancing gracefully under the command of Grandpa Feng.

2. When the autumn wind blows, the leaves of the pine trees fall slowly and slowly on the ground like butterflies, laying a carpet on the earth.

3. The leaves of the pine tree have sprung up like mushrooms after a rain.

4. The golden autumn is coming, the leaves of the pine trees are dancing like golden butterflies, and no matter who passes by there, they will pick up a leaf to make a bookmark.

5. The leaves of the pine tree are like a small fan, which fan which fan to fan away the summer heat.

6. The pine trees are tall and straight, and the leaves of the pine trees spread out like peacock tails under the blue sky.

7. In autumn, the fallen leaves are colorful, and the leaves of the pine trees are like butterflies, weaving a carpet for the earth, so that the father-in-law of the earth can wear a warm clothes.

The leaves of the pine tree resemble pointy toothpicks and thin needles.

The leaves of the pine tree are similar to those of the cypress tree, the cypress leaves are round, while the leaves of the pine tree are flattened.

Pine needles pine needles, pine leaves are generally needle-shaped, clump by bush, and look like toilet brushes.

There are two types of leaves: squamous leaves (primary leaves) are solitary, spiral-shaped, flattened and green at the seedling stage, and then gradually degenerate into membranous bracts, with or without extended growth at the base;

Coniferous (secondary leaves) spiral-shaped, radially extended, often 2, 3 or 5 needles in a bunch, born in the axils of bract-like scales, born at the tip of undeveloped short branches, the base of each bundle of needles is surrounded by a leaf sheath composed of 8-12 bud scales, the leaf sheath falls off or remains, the whole edge of the needle leaf is or has a fine serration, there is no stomatal line or stomatal line on the back, there are stomatal lines on both sides of the ventral surface, the cross-section is triangular, fan-shaped triangle or semicircular, with 1-2 vascular bundles and 2 to more than 10 mesophytic or marginal sparse endophytic resin tracts.

cones unisexual, monoecious; The male flowers are born in the bract axils of the lower part of the new branches, most of them are clustered into spike-like inflorescences, sessile, obliquely spread or drooping, the stamens are numerous, spiral-shaped, anthers 2, longitudinal lobes in the medicine chamber, the drug septum is scaly, the margins are slightly toothless, and the pollen has air sacs;

Female cones are solitary or 2-4 near the apex of new branches, erect or drooping, composed of mostly spiral-shaped bead scales and bract scales, with 2 inverted ovules at the base of the ventral (upper) surface of the bead scales and a short bract at the base of the dorsal (lower) surface.