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Origins of the Pine Bush

New York State Ice Age Map

The last major glacier to cover this area reached its maximum extent 20,000 years ago, extending as far south as Long Island. NYS Ice Age Map

The origins of the Albany Pine Bush are rooted in the glacial history of New York’s Capital District Region. Many of its geographic features seen today are the work of great masses of ice that existed thousands of years ago.

Almost 20,000 years ago during the Wisconsinan Period of the Pleistocene Age, the last major glacier to cover this area reached its maximum extent, extending as far south as Long Island. At this time, ice thickness in the Capital District may have exceeded one mile. As the glacier moved across the land, it scraped and eroded the underlying bedrock grinding the rock into a mixture of boulders, stones, sand and clay. Over a period of approximately 5,000 years the great ice mass began to melt, and the glacier retreated northward to present-day Albany.

Blocked by the receding mass of ice, the meltwater from the glacier accumulated in the Hudson River Valley forming a massive “glacial lake” spanning from present-day Glens Falls southward to Newburgh. This lake was later named Glacial Lake Albany.

Several rivers emptied into Lake Albany, among them the Mohawk River, carrying sediment ground by the glacier. At the point where the Mohawk River joined Lake Albany, large amounts of sand and gravel were deposited close to the lakeshore forming a large delta. This sandy delta underlies what today is known as the Albany Pine Bush, centered on the western edge of Albany where Colonie and Guilderland now come together.

Plants Colonized the Dunes Photo By J. Hecht

Pine barrens plants are adapted for survival in dry sandy soil. Deep roots and reduced and waxy leaves are just a few of the devices they use to absorb and hold onto water. Plants Colonized the Dunes Photo By J. Hecht

Free from the immense weight of the glacier, the land under Lake Albany rebounded and the lake drained, exposing the sandy delta. Winds further eroded and sculpted the sand into dunes that today characterize the Albany Pine Bush.

A succession of plant communities colonized and later stabilized the sand dunes culminating in vast pitch pine-scrub oak barrens that covered a significant part of the upper Hudson River Valley. This unique assemblage of species was shaped not only by the underlying well-drained sandy soils deposited by the glacier but also by a long history of periodic fires. Most of the native Pine Bush plant species depend on periodic fire for their survival, and therefore flourish following such a disturbance. In the absence of fire, the unique character of this landscape changes drastically.

Surviving perhaps thousands of years since the last glaciation, the Pine Bush today faces its greatest threats: habitat loss from development and the exclusion of natural fires. In an area that once covered over 25,000 acres, less than 6,000 acres remain intact today. Targeted as a site of outstanding biological significance, the Pine Bush is one of the most endangered landscapes in the northeastern United States.

Pine Bush Sand Dunes Photo By J. Hecht

Rolling sand dunes underlie the plant communities of the Albany Pine Bush. Pine Bush Sand Dunes Photo By J. Hecht