Pennsylvania forests 2014

Abstract

This report summarizes the third cycle of annualized inventory of Pennsylvania with field data collected from 2009 through 2014. Pennsylvania has 16.9 million acres of forest land dominated by sawtimber stands of oak/hickory and maple/beech/birch forest-type groups. Volumes continue to increase as the forests age with an average of 2,244 cubic feet per acre on timberland. Sawtimber volume has risen 24 percent in 10 years to 115 billion board feet. Net growth outpaced removals by a ratio of 2.4:1 on timberland. Additional information on land-use change, fragmentation, ownership, forest composition, structure and age distribution, carbon stocks, regeneration, invasive plants, insect pests, and wood products is also presented. Sets of supplemental tables are available online at https://doi.org/10.2737/NRS-RB-111 and contain: 1) tables that summarize quality assurance and 2) a core set of tabular estimates for a variety of forest resources. AcknowledgmentsThe authors would like to thank those who contributed to this assessment of Pennsylvania's forest resources. The dedicated and vital data collection staff who took the measurements upon which this analysis is based are:

Evaluating Inter-Rater Reliability and Statistical Power of Vegetation Measures Assessing Deer Impact

“…Within a sampling zone, a smaller 1/2500th ha microplot is nested within a larger 1/750th ha microplot. The larger, 1/750th ha microplot replicates Forest Inventory and Analysis (FIA) sampling protocols [24], and the smaller, 1/2500th ha microplot replicates the Pennsylvania Department of Conservation and Natural Resources Bureau of Forestry's sampling protocol to assess deer impact [26]. Crews collected vegetation data independently for each scale at all 5 subplots at each sampling location.…”

“…In addition to sustainable forest management, the Bureau of Forestry is responsible for the protection of rare and endangered plants, and its inventory protocols more intensively sample understory vegetation at all CFI plot locations compared to FIA methods [21]. The FIA protocol, however, provides more data on overstory conditions, stocking rates, and available timber [24].…”

Timing is Not Everything: Assessing the Efficacy of Pre- Versus Post-Harvest Herbicide Applications in Mitigating the Burgeoning Birch Phenomenon in Regenerating Hardwood Stands

“…Within the last two decades, sweet birch (Betula lenta L.; hereafter, birch) has emerged among the few species that consistently and abundantly recruit into mesophytic and northern hardwood forests of the eastern United States. Forest Inventory and Analysis (FIA) data show, for example, sweet birch sapling (2.5-12.5 cm diameter at breast height (DBH)) density increases of 11% from 2004 to 2014 in Pennsylvania and 24% from 1993 to 2007 in New York [1,2]. This upsurge is remarkable given that, unlike other species increasing in forest understories (e.g., beech (Fagus grandifolia L.)), the relative abundance of birch in the canopy is disproportionately low compared to its abundance in forest understories [1].…”

“…Forest Inventory and Analysis (FIA) data show, for example, sweet birch sapling (2.5-12.5 cm diameter at breast height (DBH)) density increases of 11% from 2004 to 2014 in Pennsylvania and 24% from 1993 to 2007 in New York [1,2]. This upsurge is remarkable given that, unlike other species increasing in forest understories (e.g., beech (Fagus grandifolia L.)), the relative abundance of birch in the canopy is disproportionately low compared to its abundance in forest understories [1]. The proliferation of birch is particularly pronounced following overstory disturbances (e.g., pests, wind, and forest harvests), leading to situations where birch overwhelmingly dominates the regeneration layer [3][4][5][6][7].…”

“…Birch increases in forest understories appear to be the 21st century analogue to the red maple (Acer rubrum L.) surge of the 20th century that has now stabilized or even declined in many regions [1,2,8]. Like red maple, birch may be considered a 'super-generalist' (sensu [9]) in that it possesses wide amplitude in key traits that confer recruitment, survival, and growth advantages under a variety of conditions, including recently disturbed stands.…”