The origin of the Albany Pine Bush

How did an inland pine barrens come to be here in upstate New York? The origin of the Albany Pine Bush is rooted in the glacial history of the northeastern United States and shaped by a history of disturbance. To begin, let's travel back in time thousands of years ago to the end of the last Ice Age, before the Pine Bush existed. Using clues present in the Capital District today, scientists are able to piece together an ancient chapter in the history of this pine barrens.

Glacier and sky

Water

Roughly 20,000 years ago, a massive sheet of ice (glacier) reached its southernmost extent over North America covering the northeastern United States and almost all of present-day New York State. Geologists estimate the glacier was one mile thick over the area where the Albany Pine Bush is today. Gradually, the climate warmed and the enormous ice sheet began to melt generating a tremendous volume of meltwater.

The meltwater flowing from the receding glacier did not drain immediately. Drainage was blocked to the south by sediments deposited by the glacier and to the north by the still-intact ice. Instead of draining, the glacial meltwater pooled forming a large lake geologists named Glacial Lake Albany. 

Topographic map showing northwest-southeast orientation of sand dunes

Sand

Rivers flowed into Glacial Lake Albany depositing their loads of rocks, sand, silt and clay. A turbulent ancient Mohawk River was one of these rivers. The Mohawk formed a river delta where it intercepted the shores of Glacial Lake Albany.

Over time, Glacial Lake Albany emptied and the sand left by the Mohawk River was exposed to the air and wind. Sand dunes of many shapes and sizes formed and migrated across the barren landscape of the early Albany Pine Bush. Seed by seed, grasses, wildflowers, shrubs and trees took hold, grew and anchored the dunes in place with their massive root systems. The inland pine barrens of the Albany Pine Bush began to take shape.

The topographic map above conveys the rolling sand dune topography of the Albany Pine Bush.

Topographic map showing northwest-southeast orientation of sand dunes

Disturbance

If it were not for reoccurring disturbance, the landscape we know today as the Albany Pine Bush could look very different. Disturbance has taken different forms including fire, severe weather events and human-induced disturbance (such as clearing land for agriculture). Above all, the presence of fire has been the most influential in shaping this landscape. 

Fire plays a variety of roles in maintaining the inland pine barrens. It consumes leaf litter and other organic material, preparing a sandy seed bed for pitch pine and other plants that require contact with sand for their seeds to germinate. Fire also maintains an open canopy allowing sunlight to reach low-growing plants including wild blue lupine.