Pitch pine and the southern bark beetle

During my internship, I got to see many beautiful and unique ecosystems in Long Island. One ecosystem that stood out is the Long Island Central Pine Barrens – a fire-adapted region dominated by scattered pitch pine (Pinus rigida) trees with a dense shrub layer. The pine barrens are naturally adapted to and dependent on fire. Fire thins the forest out, reducing competition between trees and improving their overall health. The pine barrens are ecologically and economically important to Long Island – they provide a contiguous habitat for rare and endangered fire-adapted plant and animals and they sit on top of the island’s only freshwater aquifer, purifying and protecting the island’s drinking water (http://www.dec.ny.gov/animals/99331.html).

The Long Island Central Pine Barrens are currently threatened by the southern pine beetle (SPB). SPB is a bark beetle that feeds on the vascular system of trees, disrupting the flow of water and nutrients, killing them in 2-4 months. SPB, as its name suggests, is native to the southeastern United States. The beetle has been spreading north, likely due to the warming of extreme winter temperatures. SPB was found in Long Island in October 2014 and has led to large infestations in several parks, including Wertheim National Wildlife Refuge, Connetquot River State Park, and Hubbard County Park (http://www.dec.ny.gov/animals/99331.html).

Tunnels under a pine trees bark left by the southern pine beetle (image via DEC).

Natural and managed fires in the the southeastern U.S. prevent SPB from causing significant pine mortality. Individual trees are healthier in pine barrens that are allowed to burn, increasing their ability to fight off infestation. Additionally, smoke and thinning disrupt the ability of beetle populations to communicate and organize infestation. In Long Island, the natural fire cycle is suppressed, and the SPB infestation is devastating the pine barrens. To manage the infestation, Long Island’s Department of Environmental Conservation (DEC) has been cutting down infested trees to artificially mimic the effects of fires (http://www.dec.ny.gov/animals/99331.html).

Pitch pine tree debris in an area of Connetquot River State Park that has been thinned through cutting.

In addition to thinning trees, management efforts include collecting pitch pine seed. The Long Island Native Plant Initiative (LINPI), an all-volunteer organization that protects Long Island’s native plant populations, organized three pine cone collection trips. The Mid-Atlantic Regional Seed Bank (MARSB, the organization I work for) helped coordinate the pine cone collection trips, and my field partner and I helped collect on two of the three trips and made our own collection for MASRB.

Pitch pine cones in a collection bag.

During our first collection trip, at Hubbard County Park, we learned how to collect pitch pine cones. Pitch pine cones only open, allowing their seed to disperse, when exposed to fire or heat – an adaptation to release seed in post-fire conditions, when it is easiest for a seedling to germinate and grow into a tree. We only collected from unopened cones because they still have seed inside of them. Many of the cones in the park had popped from the summer heat, but there were still plenty of unopened cones to collect on small trees or on branches that were cut down from larger trees.

A popped pitch pine cone on the left, and an unopened cone on the right.

Hubbard County Park was beautiful in October – the black huckleberry plants (Gaylussacia baccata) in the understory turned bright red and contrasted with the evergreen pines.

Our second collection was in the Dwarf Pine Plains in November. The Dwarf Pine Plains are a really cool sub-section of the Central Pine Barrens. They’re a rare ecosystem only found in three locations in the world – Long Island, New Jersey, and upstate New York. The pitch pines in these forests are very short due to the extreme acidity and sandiness of the soil, which does not hold onto nutrients or water well.

My field partner, Emily, next to some dwarf pitch pine trees.

Many of the pitch pine trees grow horizontally rather than vertically in the Dwarf Pine Barrens.

A partially popped pitch pine cone.

Lastly, we made our own collection of pitch pine cones for MARSB at Connetquot River State Park, one of our favorite collection sites. There were lots of un-popped cones on cut down trees/branches throughout the park and it was one of our favorite collections.

Our collection of pitch pine cones from Connetquot. They started popping from the heat in the seed lab, so we covered them in grates to prevent seed loss.

A healthy adult pitch pine tree at Connetquot River State Park.

Long Live the Pitch Pine!

Until next time,


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