Adapting to Extremes
Tracking Climate Impacts in the ASCC Study at Crosby Farm
We are now in the fourth year of the 20-year Adaptive Silviculture for Climate Change (ASCC) study at Crosby Farm Regional Park. This year, we had to adapt when the Mississippi River flooded in late June and July, closing access to the park and the study site. Staff and volunteers removed data instruments from the 24 research plots in advance of the flood to preserve them from water damage. The park was closed to the public, and phenology collection from volunteers and University of Minnesota technicians was postponed until conditions improved. However, data collection needed to continue, so staff adapted to this change.
In 2024, the plots experienced a combination of extreme weather events, including Minnesota’s warmest winter in a century, overall low snowfall, and extreme mid-summer flooding. Located in a floodplain forest, they were particularly impacted by this summer’s flood. The 2024 flood peaked on June 29th at a river gauge height of 20.17 feet, making it the 8th highest recorded flood crest in Saint Paul’s history (NOAA, 2024). The cause of this flood was the prolonged and intense rain throughout Minnesota that inundated the Mississippi and its tributaries, causing it to rise to major flooding levels.
Based on the need to collect weekly phenology data of the plots and a strong interest in observing how the trees in the plots immediately reacted to a historic mid-summer flood, staff from Mississippi Park Connection and the National Park Service (NPS) were assembled to collect phenology data by canoe at the ASCC plots during the flood. All staff were experienced paddlers trained in non-motorized watercraft safety. They collected data by paddling through the plots twice during the two weeks of flooding.
On the first day, staff paddled into the park and found the plots under six to eight feet of water. Collecting phenology data was challenging and involved using binoculars to view trees and phenological stages from a distance. Data collection challenges included trees being fully underwater; logs, trees, and floating debris blocking paddling routes to plots; and strong currents in plots located near the river, making it unsafe to collect data. While some plot data is incomplete because of these challenges, staff were able to collect phenology at ten of the eleven phenology plots.
From an MPC Forestry Program Coordinator Marielle Mateo’s perspective: “The first day was like entering another world. We paddled over the pathways that I had walked on a couple of weeks back. We saw fish swimming over the sidewalk, excitedly exploring new areas, crossing between Crosby Lake and the Mississippi River.”
On the second day, the flood had lowered and some plots and pathways were accessible by foot. However, the amount of debris increased, making access to some plots even more difficult. Staff collected phenology data whenever safely possible, collecting data at five of the eleven phenology plots.
After the floodwaters receded and the plots were accessible again in late July, staff and volunteers from Andersen Corporation and the community repaired all 24 plots. Staff and volunteers came together and uprighted and replaced fallen poles and fencing, removed vines and debris from fences, and patched up fencing damaged from the floods in four Crosby Crew sessions in July and August. The efforts to maintain the study plots ensure that researchers, staff, and volunteers can safely access the plots for research.
Looking to the future, our partners at the University of Minnesota will analyze this year’s data to determine how the mid-summer flood and extreme weather affected tree growth and survival in the ASCC plots. This information will help managers of floodplain forests make decisions about what species of trees to plant in light of the increasing probability of extreme weather events like major flooding. The ASCC plots now have a precedent for prepping for flooding and collecting phenology data, which will inform MPC’s management actions during future floods. As climate change brings more extreme weather to Minnesota, MPC will continue efforts to maintain and manage the area in and around the ASCC plots and support the University of Minnesota in its research.