Alternative 3: Full Host Removal

United States lists sediments as the second leading cause of impairment under Section 303(d) of the CWA (EPA, 2014c). Sediments are the ninth leading cause of impairment in lakes, reservoirs, and ponds. The source of sediments causing impairment in waterways varies; however, silviculture- related activities, such as harvesting and forest road construction, are contributing factors. These impacts would be more likely in forested areas where large numbers of trees may be removed as a result of an ALB infestation. Replanting vegetation and following silviculture BMPs will protect soils vulnerable to erosion, reducing potential for impacts to water quality.

(2) Air

Under this alternative, the potential removal of a greater number of trees could cause greater impact to air resources compared to those described in Alternative 2—Removal of Infested Trees. Loss of all host-tree species across the contiguous United States is estimated to release 13.9 million mt of CO2 to the atmosphere (appendix D). This large pulse of CO2 to the

atmosphere is unlikely as ALB spreads slowly, trees become infested at different times, and trees die at different rates. Large urban and forested areas under quarantine with a high density of ALB-host trees would see impacts on the local air quality.

Forest areas are typically a mixture of tree species. For example, in the Northeastern United States, forests are typically a mixture of hardwood and hardwood-conifer (Shifley et al., 2012); full host removal would not result in complete deforestation of an area. Emissions from tree removal and chipping activities could result in some localized impacts to air quality, but these would be reduced over time as eradication efforts are implemented.

(3) Soil

This alternative would result in potentially greater impacts to soil quality, compared to the other eradication alternatives, because both infested trees and high-risk host trees would be removed. Impacts to soil would be greatest where large numbers of trees are removed from a concentrated area.

Changes in soil temperature and moisture, as well as soil erosion and loss of nutrients in areas, can impact the ability of a forest to regenerate (Ballard, 2000). These impacts are more prevalent in cases where clear- cutting is being used for forest harvesting; however, that type of removal is not likely to occur in the Program because other non-ALB-host trees would be left standing.

Compaction from the use of heavy equipment may result in increased soil bulk density values that may limit regrowth of vegetation in areas where trees are removed. These physical impacts to soil may result in increased erosion of soil from wind and rain, both during and after tree removal. Seeding areas with grass or other vegetation reduces these types of soil quality impacts.

c. Ecological Resources

Overall impacts to ecological resources, under alternative 3, are expected to be less than those described under the no action alternative and

alternative 2 because of the prevention of ALB dispersal to non-infested areas within the United States. Impacts on a local level may be more significant to ecological resources because removal of infested and high- risk host trees may result in some fragmentation, as well as a reduction in tree density within riparian zones. While these impacts would be more localized, compared to the loss of trees resulting from the no action alternative, the impacts would be more immediate as trees would be removed at a more rapid rate than if they were lost to ALB. The extent of ecological impacts would be dependent upon the size of the infestation and the predominance of ALB-host trees in natural and urban areas. The density of host trees will likely be greater in forest areas than urban settings, potentially causing greater impacts to ecological resources in forest areas.

d. Economic, Social, and Cultural Resources

Full host tree removal would result in the removal of more trees within the quarantine area compared to the other three eradication alternatives. The extent of the impact depends on the density of host trees within the area and the intended use of the host trees. Significant impacts could occur if a quarantine area overlaps with a woodlot, forest, tree plantation, maple syrup production area, or other commercial forestry area dependent upon hardwood trees that are hosts to ALB.

Urban areas predominantly planted with ALB-host trees would see a reduction in tree cover. This may result in an initial reduction in aesthetic qualities of the landscape, as well as the ecosystem services trees provide; this includes reduction in water and sediment runoff, interception of air pollutants, and buffering from solar radiation and wind.

Restoration of areas through the planting or natural regrowth of non-host trees and other vegetation may eventually lead toward recovery of resources. Suppression in the tourism industry may occur if a high proportion of the ecological resource (e.g., park, community, etc.) falls within the quarantine area. Full host removal is expected to have less of

an economic impact compared to the no action alternative because this alternative slows the spread of ALB and leads to eradication. Compared to Alternative 2—Removal of Infested Trees, Alternative 3—Full Host Removal is expected to produce greater short-term economic impacts because of the potential removal of more host trees. However, in the long- term, it is expected that impacts would be reduced because of the

protection of forest resources.

Human Health

Alternative 3 would result in increased efficacy to eradicate ALB, and prevent its spread to new areas. In the short term, tree loss would occur from removal of infested and surrounding host trees. These removals could result in localized negative human impacts related to tree loss, such as increased stress, reduced air quality, and so on, as discussed in the no action alternative. However, in the long term, the rate and spread of tree loss due to ALB would be reduced, minimizing human health related impacts.

The potential for human exposure and risk to herbicide use is the greatest under this alternative because more trees are being removed and herbicide use would be expected to increase. Human health risks are still expected to be low based on the herbicide risk assessment included in appendix E of this EIS. In some cases, stumps may be left to allow for regrowth in areas where ALB reinfestation would not occur. When stump treatment is needed, grinding is the preferred method over herbicide treatments; therefore, while there would be an increase in herbicide use, it would not necessarily be proportional to the increase in the number of trees removed.

a. Forest Resources

Under this alternative, the Program removes host trees infested with ALB, and treats the high-risk host trees located within a ½-mile radius of