Frequently asked questions

Pesky Plant Trackers badge, plants and text

Questions are organzied into the following themes:


General questions about volunteering

How much time does volunteering take?

  • ~4 hours to complete volunteer training
  • ~2 hours to locate a plant (or plants) near you (Time and effort for this step varies based on individual circumstances.)
  • ~20 minutes to set up Nature's Notebook account
  • ~2-5 minutes per observation per plant
    • Aim to observe at least once a week
    • Add time for travel plus ~3 minutes for data entry. (If you use the mobile app, data entry happens in the field and requires virtually no additional time.)

Master Naturalists and Master Gardeners are encouraged to count Pesky Plants volunteer time toward their annual service commitments. Use the Master Naturalist or Master Gardener dashboard to report hours you spend in education, travel, and project activities.

How can I participate if I can't locate a wild parsnip or knotweed plant near me?

The Pesky Plants project focuses on just these two plants. However, there is no cut-off time to participate. This means you can begin whenever you are ready, no matter what time of year you locate a plant to observe.

Some individuals may not be able to locate wild parsnip or knotweed near them, but still want to get involved in phenology. Nature's Notebook offers many ways to observe plants and animals that are near you. In fact, there are over 1,300 species to choose from in Nature's Notebook. Some of those species are of special concern and are the subject of national campaigns. Learn more here:



About Nature's Notebook

Do I register my Nature's Notebook account as an individual observer or do I select a "partner group".

Register as an individual observer and skip the "partner group" section. Use this link to register your account:

How will Nature's Notebook know that I'm a volunteer with Pesky Plant Trackers?

Nature's Notebook can recognize you as a Pesky Plant Tracker simply by the fact that you submit observations on one of the focal species (wild parsnip, Japanese knotweed, or Bohemian knotweed).

Plus, you can earn a Pesky Plants digital badge after you make 6 observations. The badge will appear in your Observation Deck.

When adding my site to Nature's Notebook, do I create a personal site or join a "Public Site"?

Add a personal site. The Pesky Plant Trackers campaign does not use the "Public Site" feature in Nature's Notebook.

Are there videos showing me how to get started in Nature's Notebook? What about other steps?

Yes! Nature's Notebook has videos that walk you through all steps of the process


How do I use the Nature's Notebook mobile app?

Everything you need to access and use the app is here:

Does Nature's Notebook have an FAQ page?

Yes, see for answers to frequently asked questions. Topics are organized by theme and "anchored" meaning you can jump to relevant passages without scrolling.

What are "Nature's Notebook Nuggets"?

Nature's Notebook Nuggets are searchable articles written by USA-NPN staff in response to observer questions. The content covers a broad range of plant and animal species. Pay special attention to passages about "forb" and "perennial forb" species because this information will apply to both wild parsnip and knotweed plants.

How do I tell Nature's Notebook that my knotweed is var. compacta?

Start at your Observation Deck (on the website, rather than the mobile app). At the bottom of the page, click "Add or Edit Plants". A new page will open. Select the site and plant in question, and type "var. compacta" or "dwarf knotweed" in the "Comments" box. Be sure to click the orange "SAVE THIS PLANT" button before navigating away from the page.

Why does this matter? The compacta variety of knotweed has different phenology from non-compacta plants. Therefore, this information is important for analyzing data and interpreting results.

How do I tell Nature's Notebook that I'm done observing a plant that died?

More information about this step can be found here:


About observing

Should I move leaf litter to check for initial growth? Or is it better to leave that in place and wait for shoots and leaves to poke up through debris?

If possible, gently lift and then replace debris that could obstruct your view of shoots or early leaves. Materials such as dead leaves and other debris can play an important role for newly emerging plants by regulating their microclimate. Every site is slightly different so find a balance between detecting early signs of growth and leaving site conditions unchanged.

When do I begin observing? March? April? Later?

Begin when you are ready. There is no "cut-off" date after which you can no longer participate. The information below can help you determine when is right for you.

Local conditions: The appearance of initial growth and leaves varies from year to year and place to place, depending on local conditions. We expect wild parsnip and Japanese knotweed to send up shoots some time in March, possibly late March thanks to February's Arctic blast. Early-season observations are scientifically valuable, but keep in mind that local conditions also affect you. For example, make your own call about how snow and temperature affect your comfort, energy expenditure, and access to outdoor spaces.

Latitude: Plants in northern climes have condensed seasons, with shoots emerging later in spring and leaves turning brown earlier in the fall.

Locating a plant: Some observers already know of wild parsnip or knotweed in their local environment when they sign up for Pesky Plant Trackers. For others, it takes more time and effort to locate a plant to observe. Where ever you are in your process, it is never too late to begin observing. For assistance locating plants to observe, contact Abbie, program coordinator, at [email protected].

Confident plant identification: It's tricky to identify plants early in the season, before leaves unfold or grow in size. If you're not confident about what species you're looking at, email photos to Abbie for a second opinion. If you are uncertain about plant identification, you can use paper datasheets to record phenology observations. (See Nature's Notebook website for more information.)

How often do I observe?

Make observations as often as is convenient for you. Ideally, volunteers make observations once a week, or even as frequently as every two or three days, particularly during the spring and fall when plant phenology is changing quickly in many parts of the country. Phenology occurs year-round, but Pesky Plant volunteers are not expected to observe during the winter. Most importantly, you should record all the observations you make—your observations, no matter how often you make them, provide valuable data!

If you miss an observation, this is okay and there is no expectation to alert Pesky Plants staff. As a volunteer, your time is yours to give and always appreciated!

Do I need to measure plant heights?

No, measuring height is not required. Instead, focus on understanding and assessing phenophases. If you enjoy tracking height through time, record those measurements in the "comment" section of an observation.

Can I observe a plant if I am unsure what species it is?

Yes! To track a plant when you are not certain of its species, use a paper datasheet (link to PDFs below) rather than using the mobile app or the web-based form.


It's a great idea to record phenology data, even when you are not confident about plant identification. One cannot go back in time to record phenology data that were not captured. In contrast, plant identification gets better with time as plant traits become more visible and the observer gains skills.

Nature's Notebook provides guidelines on this topic here:

When am I done observing?

Wrap up your season when you are ready. There is no universal end date. The information below can help you determine when is right for you.

The plant you observe: When the plant you observe dies or goes dormant, that is a good time to pause until next year. Plants can express the seventh phenophase, 'Recent fruit or seed,' well into fall or even winter. You have the option to keep observing that phenophase or conclude your observations.

Local conditions: The timing of phenophases will vary from year to year and place to place, depending on local conditions. Expect wild parsnip that flowered to die by September. Expect knotweeds to go dormant in October or November. Late-season observations are scientifically valuable, but keep in mind that local conditions affect you. For example, make your own call about how snow and temperature affect your comfort, energy expenditure, and access to outdoor spaces.


About phenophases

How do I tell if flowers are open or not?

Flowers are considered "open" when the reproductive parts (male stamens or female pistils) are visible between or within unfolded or open flower parts (petals, floral tubes or sepals). Do not include wilted or dried flowers.

Do I count flower clusters after fruits start to appear?

If there are still some individual flowers in the cluster that have not yet wilted, then yes. If you inspect the cluster and see only spent flowers, then no. This guideline applies to the yes/no and intensity questions for the phenophases "Flowers or flower buds" and "Open flowers."

Read Nature's Notebook Nugget 8 for more details. (Suggestion: scroll down half-way to the section describing red elderberry.)


About wild parsnip

Is it safe to observe wild parsnip?

Yes, it is best to observe wild parsnip without touching it. Wear long sleeves, long pants, and gloves. Stay aware that any contact with sap is dangerous. 

For more information on safety, see:

The wild parsnip plants I observed are now dead. How do I "retire" those plants and add new ones?

More information on this topic is here:

When did wild parsnip arrive in North American and in Minnesota?

Wild parsnip was brought to North America by early European settlers for use as a food crop. The earliest record of Pastinaca sativa in the Bell Museum's collection is from 1878.

Which wild parsnip plants do I observe? Basal rosettes or flowering plants?

You may observe any wild parsnip plant, regardless of its age. All observations are valuable. Understanding wild parsnip's biology will help you interpret what you see:

First year wild parsnip plants form clumps of leaves close to the ground ("basal rosettes") and will not flower until a subsequent year. Early in the season, there may be no way to tell how old a plant is. If you observe a plant that is too young to flower, you will eventually know this because only two phenophases occur: "initial growth" and "leaves."

It is slightly preferable to observe flowering wild parsnip plants. This is because for Pesky Plants research, the most valuable information is when plants form flowers, fruits and ripe fruits. If you select and mark plants early in the season, selecting three or four individual plants can increase your chances of observing a plant that exhibits all seven phenophases.

What are "primary" and "secondary" inflorescences? 

The “primary inflorescence” is the first umbel (flower head) that appears atop a plant’s main stalk. All umbels that appear after the “primary” are called “secondary.” Secondary inflorescences are arranged on branches off the main stem.

Optional: When making Nature’s Notebook observations, use the “comment” field to remark on the status of the primary inflorescence (e.g., "primary inflorescence has closed flower buds," or open flowers, unripe fruits, ripe fruits, etc.).

You can differentiate primary and secondary umbels in the photos below:

Photo by AnRo0002 via Wikimedia Commons, CC0

Photo by R. A. Nonenmacher via Wikimedia Commons, CC BY-SA 4.0


About knotweed

Knotweeds confuse me. What are the guidelines & best practices?

Knotweed plants can be confusing because there are several kinds and it is not always easy to tell them apart. This resource includes a key for identifying knotweeds as well as guidelines on how to observe different kinds of knotweeds with Pesky Plant Trackers.

The most important points are:


  • Prioritize tracking phenology data above perfect identification. There is no way to capture phenology data from the past that were not recorded, but you can always learn more about plant identification with time.
  • You can observe knotweed phenology even if you are unsure what kind it is. Use paper datasheets. After you identify what kind it is, set it up in Nature's Notebook and transcribe your data.

What about "dwarf" (or var. compacta) knotweed?

Var. compacta Japanese knotweed (also called "dwarf knotweed") is not a separate species. Relative to non-compacta plants, it has smaller, rounder, thicker leaves and stems grow to ~3 feet tall rather than ~9 feet. For identification, see this page by Missouri Botanical Garden. More examples of var. compacta knotweeds are here:

When you use Nature's Notebook to collect data on a var. compacta plant, identify the species as "Japanese knotweed" and add a note in the comment section indicating your plant is "var. compacta". This is important because even though it is not a separate species, it has different phenology.

In order to track a knotweed plant, do I need to know what kind it is?

Yes. Knowing what type of plant you observe is important for analyzing data and interpreting results. However, because it is tricky to tell apart different kinds of knotweed, not every identification will be perfect. Do your best. Prioritize tracking phenology data above perfect identification. If you are uncertain what kind of knotweed you are looking at, use paper datasheets (PDF below) to record your weekly observations.

Nature's Notebook datasheet packet for knotweed

Can I use Nature's Notebook to observe Bohemian or giant knotweed?

Bohemian: Yes, you can use Nature's Notebook's mobile app or website to observe Bohemian knotweed. This is new as of 2021.

Giant: No, you cannot enter giant knotweed observations into Nature's Notebook's mobile app or website. At this time, giant knotweed is not listed in the USA-NPN database of organisms and for this reason, there is no way to integrate data on giant knotweed into Pesky Plants research. Nature's Notebook provides guidelines on the topic of observing non-listed organisms here:

What if I think a knotweed is one kind, but find out later it's a different kind?

This is okay and not an obstacle to participation. In fact, it is good to be open-minded to new information as it becomes available. It is normal that as plants grow and their flowers open, you observe more traits and get better at identification.

If you need to change the identification of a plant, please communicate this to Nature's Notebook staff (use this online form: This is not a correction that you can make without help from Nature's Notebook staff.

Can I observe a knotweed plant if I am unsure what kind it is?

Yes! To track a plant when you are not certain of its species, use a paper datasheet (link to PDF below) rather than using the mobile app or the web-based form.

Nature's Notebook datasheet packet for knotweed

Nature's Notebook provides guidelines on this general topic here:

About research methods

Have degree day models been built for other plants, especially invasive plants?

Yes. For example, this study on yellow toadflax (Linaria vulgaris) has parallel research applications and methods to those of the Pesky Plants project.