Citizen scientists record novel leaf phenology of invasive shrubs in eastern U.S. forests
- PDF / 1,844,267 Bytes
- 13 Pages / 547.087 x 737.008 pts Page_size
- 34 Downloads / 217 Views
(0123456789().,-volV) ( 01234567 89().,-volV)
ORIGINAL PAPER
Citizen scientists record novel leaf phenology of invasive shrubs in eastern U.S. forests Erynn Maynard-Bean
. Margot Kaye
. Tyler Wagner
. Eric P. Burkhart
Received: 2 May 2020 / Accepted: 23 July 2020 Ó Springer Nature Switzerland AG 2020
Abstract Invasive shrubs are an emergent concern in deciduous forests of eastern North America. Their extended leaf phenology (ELP)—earlier leaf emergence and later leaf off compared to native shrubs and the overstory canopy—can simultaneously provide photosynthetic benefits to invasive shrubs while negatively affecting native flora and fauna through producing novel understory shade when the overstory canopy is leafless. However, phenology varies geographically, and the degree to which ELP from localscale studies applies across the range of forests experiencing shrub invasion is unknown. In partnership with the USA National Phenology Network, we developed a citizen science campaign to record broad E. Maynard-Bean (&) M. Kaye E. P. Burkhart Department of Ecosystem Science and Management, The Pennsylvania State University, University Park, PA, USA e-mail: [email protected] E. Maynard-Bean M. Kaye T. Wagner Intercollege Graduate Degree Program in Ecology, The Pennsylvania State University, University Park, PA, USA T. Wagner U.S. Geological Survey, Pennsylvania Cooperative Fish and Wildlife Research Unit, The Pennsylvania State University, University Park, PA, USA
patterns of species-specific ELP—an otherwise prohibitively large effort. Using 1500 observations of 14 species spanning 4 years, we found that the difference in leaf phenology between native and invasive shrubs can exceed 77 days within a growing season, a gap that decreases with increasing latitude by 2.9 [1.6, 4.2] days per degree latitude in the spring, and 2.2 [0.6, 1.9] in the fall. Geographic trends in ELP provide a context for interpreting local scale phenology research while bridging inconsistent findings between existing studies and can streamline management by targeting detection and removal of invasive shrubs with leaves while natives are dormant. Furthermore, even small changes to seasonal phenology can impact forest communities, especially if there is a differential response to climate cues by nativity. After exploring broad-scale environmental variables associated with leaf phenology, we find a similar correlation with pre-growing season warmth for native and invasive shrubs, but a different relationship with dormant chill days—a variable less frequently considered for modeling spring phenology for forest productivity. Keywords Leaf emergence Leaf off Invasive plants Extended leaf phenology
E. P. Burkhart Shaver’s Creek Environmental Center, The Pennsylvania State University, University Park, PA, USA
123
E. Maynard-Bean et al.
Introduction Invasion biology is no stranger to citizen science data, which is information collected by the public to improve our scientific understanding of the world. Successful early detection progr
Data Loading...
