Downer Soil Series

The Downer soil series is New Jersey's official state soil. It sits on the flat to gently rolling uplands of the Atlantic Coastal Plain in southern New Jersey, where it formed in sandy and loamy marine sediments deposited millions of years ago when shallow seas covered the region.

Downer is an ultisol — a soil order that forms in humid climates over long periods of weathering. The defining feature is an argillic horizon, a clay-enriched subsoil layer that formed as fine particles washed down from the surface and accumulated below. The surface layers, meanwhile, are sandy and low in nutrients.

The soil is acidic throughout, with pH typically ranging from 4.0 to 5.5. That acidity, combined with the sandy texture, limits what grows on undisturbed Downer soil — but it makes the land ideal for blueberries and cranberries, two crops that demand acidic, sandy conditions.

New Jersey's soil scientists and the USDA Natural Resources Conservation Service identified the Downer series as the soil that best represents the state's dominant land type: the flat, sandy, acidic uplands of the Atlantic Coastal Plain that cover most of southern New Jersey.

The series is named for Downer, New Jersey, a small community in the Pine Barrens region of Burlington County. Naming soil series after nearby geographic features — towns, streams, ridges — is standard USDA practice.

The Downer series captures two sides of New Jersey's identity at once: the wild Pine Barrens ecosystem that covers a million acres of the southern part of the state, and the agricultural Coastal Plain that built the Garden State reputation for blueberries, cranberries, and fresh vegetables.

Digging into Downer soil reveals the story of the Coastal Plain. The surface layers are sandy and dark from organic matter. Below them is a pale, leached zone where nutrients have washed downward. Deeper is the argillic horizon — yellowed and orange-tinted from iron — where those leached materials settled. At the bottom, the original sandy marine sediment continues.

Downer soil covers the flat to gently rolling uplands of the inner Atlantic Coastal Plain in southern New Jersey. It sits where the land is elevated enough above the water table to stay well drained — not in the bogs and wetlands, but on the slightly higher ground between them.

The soil is most extensive in Burlington, Ocean, Atlantic, and Cape May counties — the heart of the Pine Barrens — and extends into Cumberland, Salem, and Gloucester counties to the southwest. This is the same zone where New Jersey's blueberry and cranberry farms are concentrated.

Blueberries are the signature crop of Downer soil. New Jersey ranks among the top blueberry-producing states in the country, and the acidic, sandy Downer profile is exactly what highbush blueberry plants require. Farmers in Atlantic and Burlington counties have grown blueberries commercially since the early 1900s, when Elizabeth White developed cultivated varieties in the Pine Barrens.

Cranberries grow in the bogs and wetlands adjacent to Downer uplands, drawing on the sandy coastal plain hydrology that keeps water tables high. New Jersey is one of the top five cranberry-producing states in the country — a connection preserved in the state's official beverage, cranberry juice.

On Downer soil that has been cleared and irrigated, farmers grow sweet corn, tomatoes, peppers, potatoes, and sweet potatoes — the vegetable crops behind the Garden State name. Where the land stays forested, pitch pine and scrub oak dominate, with Atlantic white cedar in the wetter hollows.