Pollen, primarily, is found outdoors. If your child is allergic to one of these pollens, knowing the following information will enable you to reduce the number of window openings during the corresponding allergic pollen flying season and instruct your child to minimize contact with pollen during outdoor activities. I. What is pollen? Pollen is the male reproductive cell of higher plants. Pollen falls onto the style, completes fertilization and finally forms seeds, thus reproducing offspring. Its role is equivalent to that of human sperm. Pollen is so small that its structure can only be seen under a microscope and is round or oval in shape. In some plants, pollen can be self-fertilized, that is, the same flower has both stamens and pistils, and the pollen from the stamens falls on the pistils to complete fertilization. Other species of plants must cross-pollinate, which means that in order to complete fertilization and produce seeds, pollen from one plant flower must somehow travel to the pistil of another flower of the same species to complete fertilization. Insects perform this process for some plants, called insect vectors, while others rely on wind dispersal, called wind vectors. The pollen of insect-mediated flowers is waxy, large and heavy. Precisely because the pollen grains are large and heavy, they cannot be spread by the wind. They must attract butterflies and bees through the brilliant colors of the petals, the strong fragrance, and the sweet nectar in the style, and carry the pollen to the pistil of another flower through the activities of these insects, thus achieving the purpose of reproducing offspring. It is common to hear people think they are allergic to brightly colored and scented flowers, such as roses and lilies. In fact, in most cases this is a misconception. This is because, except for flower growers and gardeners who are in close contact with flowers for a long time and may be allergic to the pollen of these plants, the vast majority of people have little contact with the pollen of these plants and are generally not allergic. The most common cause of allergic reactions is mostly the pollen of wind-borne flowers. Most of these pollens are produced from plants without showy flowers (trees, weeds, etc.) that are common on the plains. These plants produce small, light, dry pollen particles that meet the requirements for wind-borne transmission. II. Types of pollen Of all the substances that can cause allergic reactions, pollen is one of the most widely distributed. Different geographical areas tend to have different allergenic pollen. According to the pollen dispersal time can be roughly divided into three categories: 1, tree pollen: more pollination in the spring. 2, forage pollen: forage, that is, cattle and sheep can eat grass. Mostly grass plants, mostly pollinated in the summer. 3, weed pollen: mostly pollinated in autumn. Allergenic pollen in northern China mainly includes artemisia and rhododendron pollen, etc. Several common allergic pollens When your child undergoes allergen prick test, you may notice that there are several plant allergens, so let’s get to know the three more common weed allergens. 1. Artemisia absinthium, a perennial herb of the Asteraceae family, is a common weed in garden beds and lawns. It grows naturally in the moist mountains and wilderness, and is found throughout China. Artemisia absinthium grows in spring and blooms from July to October. It has a long pollination period, starting at the beginning of autumn and ending at mid-autumn, and is the main allergenic pollen in autumn in areas north of the Yangtze River. People pick the mugwort leaves or cut them off with branches when the leaves are flourishing before the Dragon Boat Festival, and dry them in the sun or shade them for use. The Dragon Boat Festival is the most popular and concentrated festival in which mugwort is used, such as inserting mugwort leaves and taking mugwort baths, which are the ancient folk customs of the Chinese people to prevent diseases and drive away evil spirits. Therefore, if your child is allergic to mugwort, you need to pay attention to whether there is mugwort growing around your home or roadside. Sometimes there is also wormwood growing on the roofs of old bungalows or buildings. 2. Ruling grass The leaves of Ruling grass are called Lala vine and Lala seedling. Except for Xinjiang and Qinghai, it is distributed in all provinces and regions in China. It is born in the ditch, roadside and farmland. It is cold-resistant, drought-resistant, fertilizer-loving and light-loving, and emerges in March-April. So children who are allergic to ragweed should be relatively careful around summer. 3, ragweed Ragweed, also known as ailanthus ragweed, is an annual herb of the family Asteraceae, and likes to be born on wastelands, roadsides, next to ditches, around fields or in farmland. It is extremely vigorous, widely adaptable, has a high seed yield, and spreads with crops, water flow and carried by transportation. Of the hundreds of pollen species, ragweed is the most pollen-sensitive. Ragweed seedlings emerge from mid-April to early May, bloom from late July to late August, and seeds mature from mid-August to early October. This plant was originally found in the United States and Canada, where it has caused tens of millions of allergy sufferers. There are no such native plants in China, but unfortunately, with the importation of agricultural products, ragweed invaded our country and gradually expanded from the coast to the interior, and now grows in the Yangtze River basin, northeast and Shandong. Ragweed is more harmful to allergic people. When ragweed blooms, the pollen drifts with the wind, and certain people inhale this pollen and develop allergies. Before the onset of the disease, people usually have itchy nose, eyes and throat, continuous sneezing, runny nose and cough. During the onset of the disease, the patient feels tightness in the chest and shortness of breath, which can lead to emphysema in severe cases. Fourth, the manifestation of pollen allergy A manifestation on the nose, whenever spring, summer and autumn come, tiny pollen is released by trees and weeds. They are dispersed everywhere with the wind, and some can enter the nasal cavity and airway with the breathing movement of people, triggering a type of seasonal allergic rhinitis called “hay fever”, which is also known as kwashiorkor fever. If the symptoms of allergic rhinitis occur only during certain pollen seasons, it is called “seasonal allergic rhinitis”, and if it occurs year-round, it is called “perennial allergic rhinitis”. The child’s nose is particularly itchy and suddenly sneezes continuously, emitting a large amount of snot and blocking the nose. The clear mucus produced by the nasal mucosa often causes coughing. Loss of smell (inability to smell) is also common, and occasionally there is a loss of taste. Seasonal allergic rhinitis in a new home can also lead to asthma. The child has an unexplained paroxysmal cough, dyspnea, white foamy mucous sputum, sudden attacks of asthma, and increasing severity. Seasonal allergic rhinitis can also be complicated by conjunctivitis, where the child’s eyes become itchy, red and watery. This eye symptom is also called “allergic conjunctivitis”. These allergic symptoms affect the quality of life and the health of the whole body, as well as the social and physical activities of the patient. V. How to deal with pollen allergy? The degree of pollen spread has a lot to do with temperature, humidity and wind speed. Therefore, during the peak of pollen spread in spring, especially on windy days or sunny days, parents should take their children out as little as possible, avoid spots with lush flowers in parks and other places, and choose upwind direction for flower viewing and photo taking as soon as possible. What is the best weather to take children with allergies outside? The best time to take children with allergies out is when it is raining. The pollen in the air has been completely taken away by the rain and the condition of children with allergies will improve significantly. In the fall, “frost” can be considered the “enemy” of pollen, so once the “frost” arrives in the fall, children with allergies will be significantly better. During the onset of pollen allergy, patients should try to go out and stay indoors. During the peak of pollen season, they should not go to parks with many trees and plants or to the wilderness, so that pollen inhalation can be reduced to a minimum; in case of dry heat or windy weather, doors and windows can be closed and wet curtains should be hung when windows are opened to block or reduce pollen intrusion; when patients are outdoors, they can wear masks.