Planting benefits for reduction in stormwater runoff are calculated per-watershed with i-Tree Hydro. The statistical model examines the impacts of topography, soil type, land use, and tree health to calculate each tree group’s impact on the water cycle over a year.

Annual runoff reiterates over the selected weather year, accounting for changes in tree growth and health using the i-Tree Engine. Cumulative runoff reduction is calculated by summing all yearly estimates.

Planting benefits for reduction in total suspended solids (TSS) is calculated from estimates of stormwater pollutant loads from White et al. (2015). Localized event mean concentration (EMC) values (mg/L) vary by watershed, land use type, and annual precipitation percentile.

Annual reductions in stormwater TSS represent the suspended solids present in the mitigated runoff volume by the tree(s). Cumulative TSS reductions are calculated by summing all yearly estimates.

Planting benefits for reduction in nitrogen and phosphorus (TN + TP) are calculated from estimates of stormwater pollutant loads from White et al. (2015). Localized event mean concentration (EMC) values (mg/L) vary by watershed, land use type, and annual precipitation percentile.

Annual reductions in stormwater TP/TN are the mass of pollutants present in the mitigated runoff volume. Cumulative TSS reductions are calculated by summing all yearly estimates.

Additions of leachable phosphorus back into the watershed are calculated using known concentrations of leachable phosphorus in leaves. Leaf biomass is calculated with the i-Tree Engine, and leachable phosphorus is derived from mg/g estimates provided by the University of Wisconsin-Madison. The 48-hour period for measuring leachable phosphorus aims to represent the asymptote for most situations.

Annual contributions to stormwater phosphorus from leaf litter are calculated based on the annual leaf biomass, with the assumption that fallen leaves will not be removed with street sweeping within 48 hours when most of the bioavailable phosphorus is leached. Cumulative contributions are calculated by summing all yearly estimates.

Net phosphorus changes in stormwater runoff are calculated by subtracting the total phosphorus mitigated in stormwater runoff from the net addition of leachable phosphorus by leaf litter. The net phosphorus is only calculated for species that have estimates of Total Kjeldahl Phosphorus (TKP) from the University of Wisconsin-Madison.

Annual net changes in phosphorus are calculated per tree group per year. Cumulative net phosphorus sums the net change across all years.

Planting benefits for reduction in stormwater runoff are calculated per-watershed with i-Tree Hydro. The statistical model examines the impacts of topography, soil type, land use, and tree health to calculate each tree group’s impact on the water cycle over a year.

Annual runoff reiterates over the selected weather year, accounting for changes in tree growth and health using the i-Tree Engine. Cumulative runoff reduction is calculated by summing all yearly estimates.

Planting benefits for reduction in total suspended solids (TSS) is calculated from estimates of stormwater pollutant loads from White et al. (2015). Localized event mean concentration (EMC) values (mg/L) vary by watershed, land use type, and annual precipitation percentile.

Annual reductions in stormwater TSS represent the suspended solids present in the mitigated runoff volume by the tree(s). Cumulative TSS reductions are calculated by summing all yearly estimates.

Planting benefits for reduction in nitrogen and phosphorus (TN + TP) are calculated from estimates of stormwater pollutant loads from White et al. (2015). Localized event mean concentration (EMC) values (mg/L) vary by watershed, land use type, and annual precipitation percentile.

Annual reductions in stormwater TP/TN are the mass of pollutants present in the mitigated runoff volume. Cumulative TSS reductions are calculated by summing all yearly estimates.

Additions of leachable phosphorus back into the watershed are calculated using known concentrations of leachable phosphorus in leaves. Leaf biomass is calculated with the i-Tree Engine, and leachable phosphorus is derived from mg/g estimates provided by the University of Wisconsin-Madison. Leaf biomass is calculated with the i-Tree Engine, and leachable phosphorus is derived from mg/g estimates provided by the University of Wisconsin-Madison. The 48-hour period for measuring leachable phosphorus aims to represent the asymptote for most situations.

Annual contributions to stormwater phosphorus from leaf litter are calculated based on the annual leaf biomass, with the assumption that fallen leaves will not be removed with street sweeping within 48 hours when most of the bioavailable phosphorus is leached. Cumulative contributions are calculated by summing all yearly estimates.

Net phosphorus changes in stormwater runoff are calculated by subtracting the total phosphorus mitigated in stormwater runoff from the net addition of leachable phosphorus by leaf litter. The net phosphorus is only calculated for species that have estimates of Total Kjeldahl Phosphorus (TKP) from the University of Wisconsin-Madison.

Annual net changes in phosphorus are calculated per tree group per year. Cumulative net phosphorus sums the net change across all years.