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Is Spring Really Slow This Year? How to Keep a Phenology Calendar to Track Seasonal Events


Phenology is the study of cyclic and seasonal natural phenomena, such as plant blooming times, insect emergence, and wildlife migration.

Here on the Eastern Shore of the Chesapeake Bay, spring seems very slow to arrive in 2018. We have had cool temperatures and a few late snows through March and into April. I feel like things should be greener. Wasn't I cutting asparagus at this time last year? But maybe I'm just impatient, since spring is my favorite season and I can't wait for it to get going. 

A great way to keep track of seasonal changes and events is through a phenology calendar. Phenology is the study of cyclic and seasonal natural phenomena, particularly relating to plant and animal activity.

Phenology calendars help you both to remember and to predict seasonal changes.

Keeping a phenology calendar can be very simple or a detailed scientific data collection project. Either way, the basic idea is to observe changes in the natural world and then record them each year. As you note bloom times, plant and insect emergence, or bird or mammal migration, you will see patterns in the timing of such events. For instance, my mom knows to within a few days when to expect her ruby-throated hummingbirds to return each year, because she's been recording their appearance on her calendar for decades. 

Phenology is fascinating when you add it to your frame of reference. It's a way to connect with nature more deeply and to practice your observation skills. When you look around, you begin to be more sensitive to changes in the landscape. You notice simultaneity and causal relationships (i.e., monarch butterflies appear and begin laying eggs a few weeks after milkweed species emerge from the ground). You start to know when to expect hummingbirds, warblers, and geese to migrate, and you look for them in the air, wondering when you'll spot the first one.

There are many practical reasons to keep a phenology calendar, as well. Let's say you have a semi-tender perennial planted in your garden. Each fall, you pile a little bit of extra mulch over the crown to protect it from the deep cold of winter. In the spring, you want to remove the mulch so that the soil warms and new shoots are able to emerge. But you don't want to take the mulch off too early, in case more cold weather comes along; and you don't want to wait too long, because the shoots might have trouble growing through the heavy mulch. A phenology calendar entry about shoot emergence could help you to know when to expect the shoots and when to time the mulch removal.

If you keep bees, phenology calendars can help you estimate and keep track of nectar flow. Nectar flow is the time of year when many trees and plants are blooming (usually late spring to early summer in the East) and bees are busy gathering as much nectar and pollen as they can. This is the time to keep a close eye on your hives and add supers or frames so they have space to expand their honey stores. If you know when the key nectar species in your area begin and end blooming, you'll be able more effectively manage your hives.

Three easy ways to keep a phenology calendar

The simplest way to keep a phenology calendar is on a paper calendar. If you can find a perpetual calendar, that might work well - simply record the year and the observation for any given date. If you Google phenology calendar templates, you'll get more ideas, such as how to create a phenology wheel, which records events in a tidy graphical display.

I keep a simple and very ad hoc phenology calendar in my Google Calendar. I set up a separate calendar under my account and called it "Phenology Calendar." That way, I could view my observations separately from my personal calendar events. I also shared it with several others, who are able to contribute to the data. The key in a Google Calendar setup is to be consistent in how you record things (and always start your event titles with the year you make the observation), and to make sure to set them to recur annually, so you see your observations from previous years.

As you can see in the graphic below (click on the image to enlarge it), I have not been overly systematic in my notes so far, but it's always fun to look through and see what happened when in past years. It is very handy to look back at when the last snowfall tends to arrive, or which week is typical for peak raspberry harvest. 

I could get much fancier with color coding, notes, adding images, locations, reminders, etc. For my purposes, this level of simplicity has been working well, and if I'm outside and notice something, I can pull out my phone and add an observation in 30 seconds or less through the Google Calendar app.


You can keep your own phenology calendar using recurring events in Google Calendar.

Be a citizen scientist: Participate in Nature's Notebook


Nature's Notebook is a citizen science project of the USA National Phenology Network. You can sign up to be an observer and contribute phenology data from your area to the nationwide dataset.

A third way to keep a phenology calendar is online. One great option is to participate in Nature's Notebook, a project of the USA National Phenology Network. Citizen scientists from all over set up accounts and submit observations. Those observations are collected in a nationwide database to track phenological information, which can be used for scientific research purposes. This kind of widely reported data is very useful for observing and predicting the impacts of climate change, for example. 

It only takes a few minutes to sign up on the Nature's Notebook website. Once you find your way around, you can choose to observe just one or two plants, or a whole host of plants and animal species. Each week, you return to the same individual plants (or sites) and note changes that you see. After entering them, you can display your observations online and visualize them in context with previous years' observations, or other observers' data in your area. 

Do you keep a phenology calendar? If so, what format do you use, and how has it helped you become more attuned to nature? Please share your experiences using the comments section below. 



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