In the city

Cities are full of nature and opportunities to witness phenology.

What makes a site excellent for observing phenology is not how "wild" it is, but rather, how suitable it is for you to spend time, slow down, and pay attention to living beings around you. For many people, that place is a city, suburb, or town.

Cities are like laboratories for learning how urbanization influences phenology. In a city, seasonal patterns can differ substantially from patterns in nearby, less urban environments. This does not mean that urban phenology data are less valuable than data from undeveloped areas. To the contrary, urban phenology data can increase our understanding of complex processes of environmental change.

Examples of what makes urban phenology distinctive

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Urban heat island

The Twin Cities metro is typically about two degrees Fahrenheit warmer than surrounding areas [1]. This can influence the rate and timing of plant development, as well as the behaviors and distribution of animals.

[1] Dubos, Monique (2015), Twin Cities heat island study yield surprises. University of Minnesota - Institute on the Environment Press Release. http://environment.umn.edu/news/twin-cities-heat-island-study-yields-surprises/

Artificial light

A group of scientists explored the possibility that light pollution could play a role in plant phenology [2]. They compared phenology observations from artificially lit cities against observations from naturally darker, surrounding landscapes. They found that in addition to the effect of temperature, artificial light is associated with earlier spring greening and later fall color.

[2] Meng, Lin. "Green with phenology." Science 374, no. 6571 (2021): 1065-1066. Link to this article in SCIENCE >

Practical applications

No matter the setting, information about phenology has practical applications. Some examples of how cities utilize phenology information include making schedules for street sweeping; controlling mosquito populations; and predicting peak allergy seasons based on concentrations of grass, tree, and weed pollens.

Suggested plants and animals for city-dwelling people

Basswood trees

Many kinds of trees are easy to observe in cities. One example is the American basswood, which is commonly planted along city streets and in urban green spaces. The phenology of basswoods brings many delights to a city dweller, from fragrant flowers, to a shady canopy, to brilliant golden color in autumn.

Profile for American basswood (Tilia americana)

Chimney swift

As their name suggests, chimney swifts often nest in chimneys, and take shelter in a variety of human-built structures. These small birds are relatively abundant in cities and present in Minnesota from late April through September.

Profile for chimney swift (Chaetura pelagica)

Common dandelion

Remember how much fun a kid has making dandelion flower chains and blowing seeds into the wind? Phenology lets you tap into that childlike curiosity by looking closely at ordinary weeds and taking interest in all there is to learn by examining their leaves, flowers, and fruits. Dandelions make an ideal study subject because even in densely urbanized areas, they are abundant, easy to find, and convenient to observe.

Profile for common dandelion (Taraxacum officinale)

More suggestions

Start by getting outdoors in your everyday environment and deliberately slowing down. Uncertain where to go? Consider any short walk you take to drop off mail, walk a dog, get to the bus stop, or simply breathe fresh air. Take note of trees and other plants that grow in your everyday environment. Then notice any animals that visit or take shelter near those plants. If you cannot identify the species you are looking at, ask an expert, or upload a photo to iNaturalist where an online community can help identify your observation.

Some of the species you are likely to find in or near cities are listed below, organized by landscape features. Nature's Notebook supports phenology observations on an even greater variety of plants and animals.