Mission: Native vs. Invasive Shrub Phenology

Multiflora rose, VS user 2017mwo7

Research Question

How is climate change affecting the timing of seasonal changes in native and invasive shrubs?

You're Invited

Researchers have found that climate change is causing shifts in the timing of when leaves of trees and shrubs emerge and fall during the year. With these changes, how will native and invasive shrubs fare? Will hearty invasives hold onto their leaves longer and gain an advantage in warmer temperatures? More investigation is needed! Can you find a difference between the phenology of native and invasive shrubs?

Mission Steps

Multiflora rose, VS user flowerpowergirls
  1. Choose native and invasive shrubs to monitor in your area:
  2. Gather your materials for fieldwork, including your Vital Signs Upland Species and Habitat Survey datasheet and the species ID card for the native and invasive shrubs that you will be monitoring.
  3. Go look for your species! Look around your field site. Document evidence of what you found (or did not find) on the Vital Signs Species and Habitat Survey. Record the number of minutes you spent searching in your field notes.
  4. mission_phenology_101417_ad_72.jpg
    Burning bush, VS user AD 72
  5. Record the phenophase you observe for each shrub you find in your field notes. The phenophase is the stage in the plant’s yearly life-cycle, and it begins with the first leaf that changes. Phenophases to look for include:
    • No leaves
    • Breaking buds
    • Full leaves
    • Colored leaves
    • Falling leaves
  6. If you can, return to your field site once or twice a week until you observe a change in phenophase. Mark the date of the change in your field notes.
  7. For each shrub species that you are monitoring, post at least one observation to Vital Signs.
  8. Return to the same field site around the same time each year to see how the phenology of your species is changing over time.

Why this Mission Matters

Morrow's honeysuckle, VS user Nature Ninjas

When the trees are bare in the early spring and late fall, light is able to reach the plants on the forest floor. During these short periods, invasive shrubs compete with native shrubs for light, a critical resource for plants. Researchers have begun to notice that some invasives grow their leaves earlier in the spring and others shed leaves later in the fall, blocking light from their native counterparts. This phenomenon is called extended leaf phenology, and it means that native shrubs may not have access to sunlight they need to survive.

As our climate warms, trees and shrubs are able to hold onto their leaves for greater amounts of time. What will this change mean for native and invasive shrubs? Which shrub species will be able to take advantage? Your research is needed to find out!

Teacher Resources

Find useful information and resources for conducting this investigation with your class on the Mission: Native vs. Invasive Shrub Phenology Teacher Resources page.