Improve invasive plant management using climate based phenology models

researchers pose for a photo in a field with a wild parsnip warning sign

Research team members


Understanding plant phenology is important for predicting the annual timing of key plant growth stages like flowering or seed development, which are controlled by environmental factors like temperature and sunlight availability.

Currently, management activities tend to use calendar days for predicting phenology and timing of management. However, phenology is strongly regulated by temperature. Thus, scheduling management using temperature-based predictions of phenology could be more effective. 

This research team sought to develop better information on the timing of life cycle events and how they relate to temperature on two priority invasive species: wild parsnip (Pastinaca sativa) and Japanese knotweed (Polygonum cuspidatum). 

Research questions

  • How do temperature and photoperiod affect the phenologies of wild parsnip and Japanese knotweed in Minnesota?
  • When are important phenological events for wild parsnip and Japanese knotweed likely to occur in different parts of Minnesota?


Montgomery and her team developed climate-based phenology models of key phenological events such as flowering and fruiting. To collect data for the models, they created and nurtured a robust citizen science network called Pesky Plant Trackers. In addition, there were 5 University field plots across Minnesota from which they collected data. Overall, they trained 96 volunteers; 80 contributed data on 255 plants (180 planted) or patches of plants located at 64 sites.

Phenological data on Japanese knotweed and wild parsnip is available on along with a guide on how to use the data (see project artifacts). Land managers can use the data to estimate phenology of these species given current and projected seasonal temperatures.

Project artifacts


  • Pesky Plant Trackers citizen science program, online training module, and monthly newsletter
  • Pesky Plant Trackers YouTube channel
  • Contributor to Annual report from USA National Phenology Network
  • Invasive Species Conference at UMN Research and Outreach Centers, 2022
  • Mentored UMN Master-Naturalists-in-training for capstone projects, 2022
  • UMN Gathering Partners Conference, 2021, 2023
  • “Annual Short Course” for Minnesota Association of Country Agricultural Inspectors, 2021
  • Open Lands Chicago, 2021
  • Anoka County Master Gardeners gathering
  • Citizen Science Association of America
  • Franconia Sculpture Park event

News and media

Research team

Rebecca Montgomery | principal investigator

Stephan Carlson | co-principal investigator

Abbie Anderson | citizen science coordinator

Byju Govindan | researcher

Amy Morey | researcher


Lab or other website

Pesky Plant Trackers


Collaborating organizations

USA-National Phenology Network

Oregon State University

Minnesota Department of Agriculture

Minnesota Department of Transportation

Master Gardeners, UMN