Pine leaves harden and turn yellow, and they fall off at the touch?

Should be dead, the reason why pine leaves turn yellow:

1, pine leaves are not strong after transplanting, but generally lack of iron. Foliage fertilizer is generally used. In areas where pine leaves are yellow and iron deficiency is serious, iron fertilizer must be applied in coordination with the soil, and Trim foliar fertilizer can be sprayed on the leaves.

Commonly used iron fertilizers include ferrous sulfate, ammonium ferrous sulfate, ammonium ferrous sulfate and synthetic complex iron such as ferric citrate, EDTA-Fe and EDDHA-Fe. In most cases, the effect of soil application is not obvious, mainly because iron will be quickly converted into insoluble oxides.

2. Because the newly transplanted pine trees have been planted for a short time, the new roots have not been formed, and the old roots have not recovered their absorption function, which leads to the imbalance of tree nutrition due to lack of nutrition and water.

3. Due to the high weather temperature, trees lose water seriously.

4. Because of the unbalanced nutrition, the stress resistance of trees is reduced and tree diseases occur. Common diseases include dead tip disease and needle drop disease, which are easy to cause yellowing.

5. Another factor that pine leaves turn yellow is the soil problem. Although the requirements for soil quality are not strict, it is best to use sandy soil rich in humus. If other reasons cannot be ruled out, the owner will see if the soil is qualified.