Dandelions by the Roadside

Do you remember when was the last time you blew dandelion seeds? Do you remember the last time you stopped your busy schedule and noticed a dandelion blooming? As far as I can remember, I haven’t done this since I was in primary school.

Why are dandelions becoming more and more rare in big cities?

The natural environment and the survival of species are facing great challenges as a result of urban development. In my country (China), on the one hand more and more people are gathering to work and living in big cities (like Shanghai and Guangzhou), resulting in the need to provide more living spaces and public facilities. On the other hand, the rapid growth of cities has led to their increasing size. What was once a suburb, the countryside, is now part of the urban area. The expansion and construction of cities may cause some animals and plants to lose their habitats. At the same time, the planning and design of urban greenery and the frequent and excessive mowing of lawns have an impact on the growth of dandelions.

Dandelions in bloom – spring has arrived.

During my postgraduate studies at the University of Leiden, I had more time to pay attention to the changes in nature. Because of this, I noticed dandelions once again. In Leiden, when the temperature was starting to rise slowly in April, I suddenly noticed that the grass was covered with yellow flowers – dandelions! Spring has already arrived.

Although dandelions originated in Europe, they are found throughout the northern hemisphere. They can not only grow from sea level to alpine elevations, but also adapt to various types of soil. They can be found in parks, on the sides of roads, in farmland and many other places. Dandelions are valued for their wide range of uses, including as medicine and food, around the world. As a medicine, dandelions have been used for the prevention and treatment of cardiovascular disease, type two diabetes, liver disease and more. In addition, many people consume dandelions as part of their food:  its leaves are used as salad and flowers can be used to make wine.

Understanding dandelions through careful observation

If you take time for careful observation, you may start to observe fascinating characteristics of this common urban plant as I have. For example, the opening and closing of the inflorescence (flower head). The flower head opens during the day then gradually closes as it gets dark. It is interesting to note, however, that it is not always in full bloom during the day and careful observation is needed to identify patterns: it is also affected by rain and will close during rainy days. These observations are in general agreement with the findings of botanists.

Dandelion open during the day

Dandelion closed at night

Dandelion closed in the rain

Another observation I made is on the color of the dandelion’s seeds. Dandelions have a large number of seeds (which we also call achenes) attached to their seed heads. The achenes have elongated stems at the top and end in a parachute shape. These seeds are lanceolate and arranged in regular rows on the seed head. Usually, the achenes are straw to brown colored. But there are special cases when they are reddish brown in color. Unfortunately, I have not found such dandelions. When dandelion seeds have blew out by high winds, the seed heads are completely exposed, and at this time they can be seen with multiple white spots.

Dandelion seed head

Dandelion seed head

Dandelion after seeds have dispersed

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