Thank you for your question. The good news is that there are several native trees and shrubs suited to the Hudson Valley that can tolerate periodic flooding and provide an effective privacy screen.

Based on your description, the site appears to have poorly drained soil, since a 1-foot-deep test hole remained full of water for more than 24 hours after rainfall. Selecting plants adapted to wet conditions will give you the best long-term success.

Serviceberry (Amelanchier spp.) can tolerate moist soils and occasional flooding, especially species such as smooth serviceberry (Amelanchier laevis) and downy serviceberry (A. arborea). However, serviceberries generally prefer well-drained to moderately moist soils rather than sites with persistent standing water. They may survive but would not be my first choice for the wettest portion of the site.

Swamp white oak (Quercus bicolor) is an excellent choice. As its common name suggests, it is naturally adapted to bottomlands, floodplains, and poorly drained soils. It tolerates seasonal flooding better than most oaks while providing substantial screening value as it matures. Although it grows more slowly than many shrubs, it can become a beautiful, long-lived native specimen tree.

Pussy willow (Salix discolor) is another very good option. This native shrub naturally occurs in wetlands, streambanks, and other moist habitats and tolerates standing water much better than most landscape shrubs. It grows relatively quickly and can provide screening sooner than oaks.

Bear oak (Quercus ilicifolia) would not be recommended for this location. Bear oak is typically found in dry, sandy, and well-drained soils and is poorly adapted to wet conditions. It would likely struggle in a site that experiences standing water.

For a privacy screen, consider combining several native species to improve wildlife value, visual interest, and resilience. Native shrubs that tolerate wet soils include:

• Pussy willow (Salix discolor)
• Buttonbush (Cephalanthus occidentalis)
• Winterberry holly (Ilex verticillata)
• Red osier dogwood (Cornus sericea)
• Silky dogwood (Cornus amomum)
• Elderberry (Sambucus canadensis)

If screening is needed relatively quickly, a mixed planting of pussy willow, red osier dogwood, silky dogwood, and winterberry could provide good density within a few years. Swamp white oak could then serve as a longer-term canopy tree within or behind the shrub planting.

One additional consideration is the duration of flooding. Many of these species tolerate temporary standing water following storms, but if water remains for extended periods throughout the growing season, plant selection becomes even more important. If possible, you may wish to observe whether standing water is limited to major rain events or persists regularly. Bringing in a landscaper who specializes in drainage to address the standing water can help you fully evaluate your options. Before installing any drainage system, be sure to contact your town to confirm local requirements and property offset rules.

Additional resources

• Cornell Cooperative Extension: Trees and Shrubs for Wet Sites
  https://ccenassau.org/resources/selecting-trees-and-shrubs-for-wet-sites

• Penn State Extension: Landscaping Wet Areas in the Home Garden
  https://extension.psu.edu/landscaping-wet-areas-in-the-home-garden

• University of Kentucky Cooperative Extension: Native Trees for Wet Sites
  https://forestry.ca.uky.edu/native-trees-for-wet-sites

• University of Minnesota Extension: Trees and Shrubs for Wet Soils
  https://extension.umn.edu/planting-and-growing-guides/trees-and-shrubs-wet-soils

• Missouri Botanical Garden Plant Finder (excellent cultural information for individual species)
  https://www.missouribotanicalgarden.org/plantfinder