Are catkins floating all over the street now? So what is catkins of willow? Speaking of the origin of flying catkins, it can be traced back to the 1960s when Beijing began to plant trees on a large scale. Because there were few greening trees at that time, and poplar trees grew fast and had good landscaping effect, it was listed as the 'backbone' tree species to plant trees on a large scale. There were nearly 400000 female willows in the six districts of the city.
Poplar grows for about 6 years, reaches maturity, and begins to blossom and bear fruit.
After flowering, male poplars naturally shed their spikes; after flowering, female poplars form fruits, and when mature, the small fruits crack, and the fluffy seeds fly around like dandelions, and then root and germinate after falling to the ground.
Poplars generally begin to age at 20 years old, and various' senile diseases' appear. The older the trees are, the more flying catkins they produce.
According to the city's Landscaping Department, the city has the technology to control willow catkins. In recent years, various measures have been taken to control catkins.
The control measures include stopping planting the plants that produce flying catkins, renovating the female old poplar trees and replacing them with male ones, spraying the poplar trees with insecticides to make the flying catkins abortion, etc.
Experts from Beijing Academy of agriculture and Forestry Sciences have also developed a "female inflorescence dispersant" to inhibit the formation of poplar flocs.
Why is it that when planting willows, many people, regardless of gender, make the sky full of catkins, which affects the environment?
Question details:
Recommended answer: to put it simply, willows can be divided into male and female, most of them are dioecious, and catkins are produced by females. There are several reasons for not distinguishing male and female. First, it is difficult to judge male and female of willows except when catkins occur in spring, and the sexual characteristics are not obvious.
Second, many green willows were planted many years ago. At that time, the environmental impact was not very important.
Third, most of the nursery in the seedling stage because of technology and cost is not separate.
In recent years, there has been a great improvement. There are separate breeding seedlings and new varieties in the nursery. In addition, for those already planted, with the aging of seedlings, they are gradually replaced by other varieties.
Speaking of the origin of flying catkins, it can be traced back to the 1960s when Beijing began to plant trees on a large scale. Because there were few greening trees at that time, and poplar trees grew fast and had good landscaping effect, it was listed as the 'backbone' tree species to plant trees on a large scale. There were nearly 400000 female willows in the six districts of the city.
Question details:
Recommended answer: to put it simply, willows can be divided into male and female, most of them are dioecious, and catkins are produced by females. There are several reasons for not distinguishing male and female. First, it is difficult to judge male and female of willows except when catkins occur in spring, and the sexual characteristics are not obvious.
Second, many green willows were planted many years ago. At that time, the environmental impact was not very important.
Third, most of the nursery in the seedling stage because of technology and cost is not separate.
In recent years, there has been a great improvement. There are separate breeding seedlings and new varieties in the nursery. In addition, for those already planted, with the aging of seedlings, they are gradually replaced by other varieties.