HomeMy WebLinkAbout2025 Arrowhead Lake POI Survey Report2025 Arrowhead Lake (DOW: 2700500, Hennepin County)
Aquatic Vegetation Point Intercept Survey Report
4/18/2025
An aquatic vegetation point intercept survey was completed in Arrowhead Lake on 4/18/2025 for
the City of Edina. The point intercept survey consisted of 128 points. At each site depth was
recorded and vegetation was sampled with a double-sided rake. For every species sampled, an
abundance rating was assigned based on how much was sampled on the rake. The ratings are as
follows:
0. Plant species absent
1. Plant species covers <25% of the rake
2. Plant species covers 25-75% of the rake
3. Plant species covers >75% of the rake
This rating scale was taken out of the Minnesota Department of Natural Resources Guidance for
Delineating Aquatic Plants for Management.
Table 1. Plant species found in Arrowhead Lake in 2025 with the number of sites where it was sampled and average rake
abundance when it was sampled.
Plant Species 0 1 2 3 Frequency Avg. Rake Abundance
Chara 75 27 6 20 41 1.8
Curlyleaf Pondweed 104 18 5 1 18 1.3
Leafy Pondweed 119 9 0 0 7 1
White Waterlily 122 6 0 0 5 1
Coontail 127 1 0 0 0.8 1
Curlyleaf pondweed was the 2nd most abundant plant species in Arrowhead Lake (See figure 1) in
2025. It was found at 18% of sites which was down from 2024 when it was sampled at 66% of sites.
The average rake abundance was down from 2 in 2024 to 1.3 in 2025.
Chara spp was the most abundant plant species in Arrowhead Lake (See figure 2). It was found at
41% of sites which was up from 3% in 2024. (frequency of occurrence: 3%) The average rake
abundance was 1.8 which was up from 2024 at the sites where it was collected.
Three new species were collected in 2025: leafy pondweed, white water lily, and coontail. Common
waterweed was not collected in 2025; however, it was sampled in 2024.
Figure 1a: 2025 Arrowhead Lake CLP distribution and abundance.
Figure 1b: 2024 Arrowhead Lake CLP distribution and abundance
Figure 2a: 2025 Arrowhead Lake Chara distribution and abundance
Figure 2b: 2024 Arrowhead Lake Chara distribution and abundance
Figure 3: Arrowhead Lake leafy pondweed distribution and abundance
Figure 4. Arrowhead Lake white waterlily distribution and abundance