Content
Unlike other representatives of evergreen coniferous trees, larches turn yellow and shed their needles every autumn, as well as when certain unfavorable factors occur. This natural feature is very unusual and has several causes and explanations.
Do larch needles fall?
Larches are long-lasting and hardy trees. These plants are able to adapt to various natural factors and quickly cover new territories. The needles of the culture look like needle-like leaves of different lengths. They are soft, unlike spruce and pine needles, since they do not have hard mechanical tissue inside. Like all deciduous plants, every autumn larch turns yellow and sheds its green outfit, which is why it got its name.
In spring, it is covered with young bright green leaves, which over time change their shade to dark: thus the needles become more like needles. Cones appear on the branches of the plant. Their size and quantity depend on climatic conditions and region of growth. In autumn, the larch turns yellow and falls, covering the soil with a beautiful carpet of lemon-yellow hue. All winter the trees stand with bare branches.
In winter, buds appear on the branches again, looking like small spherical tubercles: in appearance they differ from the buds of other conifers. With the arrival of spring, shoots that are different from each other appear from them. The uppermost bud produces a long stem with single needles. When the lateral buds bloom, a short bunch is formed, combining many small needles growing in different directions. The stem is not developed here, and the soft needles are closely collected at one point. One bunch contains several dozen needles.
Why larch sheds its needles for the winter
It is assumed that in ancient times larch was evergreen. But, having found herself in regions of the far north characterized by a harsh climate, she was forced to turn yellow in order to adapt to new conditions in this way. Larch sheds its needles in the winter in order to reduce water evaporation during the cold period. The tree goes into economic conditions, because in winter the soil freezes through and through, and the roots of the plant are not able to extract a sufficient amount of moisture.
In addition, the needles themselves contain a certain amount of water, which helps them remain soft and fluffy. The surface of the needles, which protects the plant from moisture loss, has a very thin protective layer that helps adapt only to the warm season. Before the onset of cold weather, the larch turns yellow, the leaves fall off the tree to prevent it from freezing.
Reasons for yellowing of needles in summer
Unlike deciduous trees, larch is very rarely exposed to pathogenic microorganisms due to the fact that its composition includes phenolics, tannins and resins.However, like any other plants, larch can still be exposed to various diseases and pests, as a result of which its needles may turn yellow before autumn. In case of disease, putrefactive bacteria and fungi primarily affect the needles. Most often, larch is attacked by the following diseases and pests:
- Schutte mushroom infects trees in May-June under conditions of high air humidity. At the same time, the larch turns yellow. The disease can be identified by the appearance of red-brown spots on the tips of coniferous leaves. Larch needles fall off. To protect the plants, from July to September the crowns are sprayed with Bordeaux mixture or 2% colloidal sulfur.
- Melampsoridium fungus leads to rust. The needles of the plant turn yellow and become spotted. For prevention purposes, trees are sprayed with fungicidal agents. In addition, they try not to plant larch next to birch, which is an intermediary in the transfer of the fungus.
- Hermes aphid - a type of insect that sucks juice from young needles. The needles turn yellow, dry out and fall off. Individuals of the spruce-leaf Hermes form green growths on the shoots - galls, reminiscent of velvet. The needles become yellow at the site where the aphids are sucking, become deformed and curl. Shoots with such growths always die. Insecticides containing mineral oils will help in the fight against hermes. These substances are capable of dissolving the protective wax coating of pests.
To care for a tree, you must follow the basic rules:
- Larch needs to be watered and fed in a timely manner, broken, dried branches and falling needles must be removed so that parasitic insects do not infest it.
- Damage to the bark must be covered.
- It is recommended to loosen the soil and mulch with hay, peat, sand, sawdust, and manure.
Conclusion
Larches turn yellow at different times of the year for different reasons. These can be natural processes, as well as a consequence of exposure to unfavorable factors. Young seedlings retain green needles throughout the year. Mature larch trees shed their needles in winter in order to acquire a new green outfit in the spring, which will delight you with a spectacular appearance until the fall. If the crowns of plants turn yellow in the summer, it means that the larch needs protection and treatment with special means against various pathogens.
