SCIENCE & TECHNOLOGY

New Visualization of Browse Impacts Points to Restoration Challenges in Deciduous Forests of the Midwest and Northeast By Will McWilliams

Browse damage by white-tailed deer on black cherry (Prunus serotina Ehrh.). Photo: Manfred Mielke, US Forest Service, Bugwood.org

orest managers and policymakers overabundant invasive plants or building results. Moderate or high impacts signal of deer was likely to lead to overbrows- rely heavily on broad-scale spatial and maintaining an exclusion fence, are to forest managers the need to consider ing (Figure 2). The concern was that plant Finformation to better channel scarce expensive. The issue is exacerbated be- site-specific conditions prior to making species with little or no nutritive value funds to address important issues, espe- cause private owners control 72 percent of stand-regeneration prescriptions. would gain a competitive advantage. cially those related to restoration. The forestland, and these treatments are eco- Our new approach shows that areas abundance of white-tailed deer (Odo- nomically challenging for most of them. What Is Revealed? of concern have expanded to Illinois, In- coileus virginianus) and their impact on About 60 percent of the 182.4 million diana, Ohio, West Virginia, Maryland, young-forest habitat (YFH) establishment Browse Impact Monitoring acres of forestland inventoried in the Delaware, New Jersey, and the southern and development qualifies as such an is- Monitoring results for large ungulate ef- Northeast and Midwest were estimated to New England states. Comparing the Leo- sue. Restoring broadleaf deciduous forests fects on forest regeneration were obtained have moderate or high browse impacts. pold map to the more-recent map (Figure in the Midwest and Northeast has become using new measurement protocols cover- Ecological provinces of the Mid-Atlantic 1) indicates that there are no areas where nearly impossible in many areas, because ing regeneration and browse as part of the region ranked highest among ecological concern was reduced or disappeared en- deer are devouring the next generation of three-phase forest inventory conducted by subdivisions, with 79 percent of the for- tirely. trees. With YFH increasingly rare and in- US Forest Service’s Forest Inventory and estland in this region in these impact cat- vasive plants and pests expanding, forest- Analysis (FIA) branch. In Phase 3, data for egories. The maple/beech/birch and oak/ What This Means for Restoration ers are faced with a serious challenge. a suite of enhanced ecological indicators hickory forest-type groups were above av- These results were recently published The difficulty of establishing healthy are collected during the summer season. A erage, with 65 percent and 69 percent, re- in US Forest Service General Technical YFH (defined as 20 years or younger) has regeneration indicator (RI) was added as a spectively, with moderate or high browse Report NRS-182. The report includes a come to the forefront of policy because Phase 3 component in 2012 (McWilliams impacts. review of the implications of browse im- YFH comprises only 7 percent of each re- et al. 2015). The RI protocols include Assessing trends in browse impacts pacts for managers attempting to restore gion’s forestland. Maple/beech/birch and browse-impact severity evaluation and across large areas is fraught with diffi- YFH in areas under browse stress. The oak/hickory are the most prevalent for- seedling measurements. (The core FIA na- culties because such studies are typically authors affirmed three broad realities for est-type groups in terms of acreage, but tional standard is to count all seedlings at too small in scale or limited to thematic restoration management during the stand only 3 percent and 4 percent, respectively, least one foot tall.) results that lack detail and repeatability. initiation phase: is YFH. Such low percentages send up red A team of specialists used the browse One approach is to examine the earliest flags for restoration efforts. It takes a lot data to predict the probability of moder- subcontinental-scale visualization and 1. The scope and persistence of her- of time to develop acceptable advance re- ate or high impacts on regeneration (see look for broad trends. In 1947, Aldo Leo- bivory has long-term, wide-ranging generation in these forests, and restorative Figure 1). The predictions are in the form pold and others identified problem areas implications. prescription options, such as control of of a visualization (visual display) of the in the United States where overpopulation 2. Less-palatable tree species will

8 The Forestry Source “It Looked like a War Zone.” Recovery Efforts Underway after Yutu By Andrea Watts

Figure 1. Probability of occurrence for moderate or high browse impacts on forest land, Midwest and Northeast, 2017.

On October 24, 2018, Super Typhoon Yutu slammed into the Northern . The US Forest Service deployed an urban forest strike team to assist with the recovery efforts. Photographs courtesy of the US Forest Service Pacific Southwest Region 5.

ith much of the country still ing to see the damage that Yutu caused. It focused on the damage assess- looked like a war zone; it was almost like Wments from Hurricane Mi- we were at war with Mother Nature, and chael, Super Typhoon Yutu’s devastating we lost tremendously. Trees were broken effects upon the Commonwealth of the in half or uprooted, power poles and lines (CNMI) didn’t were down and blocking roadways, and receive much coverage. According to NA- homes were torn or ripped apart. SA’s Earth Observatory, Super Typhoon Yutu tied Super “as What work did the US Forest Service ur- the strongest storm on Earth this year ban strike team undertake? and is likely the strongest to make a di- The urban strike team played an import- rect hit on the Mariana Islands since mod- ant role in recovery efforts. They helped ern record-keeping began.” Wind sensors fill overhead positions, cleared debris, recorded maximum sustained winds of removed downed trees, and helped make around 180 miles per hour. primary roads accessible. We are thankful CNMI is a commonwealth of the for their assistance. United States; it was the scene of a cru- Figure 2. Areas with overpopulations of deer as of 1947 (Leopold et al. 1947). Numbers refer to case histories. cial battle between the US and Japan in Did some tree species survive the wind Used with permission of Wiley Inc., with copyright retained by The Wildlife Society. World War II. Of its 14 islands, , better than others? , and Rota are where the majority From our general observation, we saw that continue to have a competitive advan- Spencer. 1947. “A Survey of Over-Popu- of the population lives. Collectively across some tree species survived the wind better tage during the regeneration phase lated Deer Ranges in the United States.” the CNMI, there is 60,206 acres of forest- than others. We noticed that trees smaller and are likely to be different species Journal of Wildlife Management. 11: 162– land, 4,000 acres of which are nonindus- in diameter, such as the palm tree fami- from current canopy dominants. 177. https://doi.org/10.2307/3795561. trial private forestland. I e-mailed Martin ly (coconut trees), sustained less damage 3. Success will require more emphasis McWilliams, W.H., J.A. Westfall, P.H. Pangelinan Jr., the state forester for CNMI, compared to the trees that are bigger in on ungulate-compatible prescriptions, Brose, et al. 2015. “A Regeneration Indi- asking him to share the state of CNMI’s diameter, such as mango trees and pine novel approaches, and adaptive cator for Forest Inventory and Analysis: forests after Super Typhoon Yutu and the trees. After some thought, it was clear that science. History, Sampling, Estimation, Analytics, recovery efforts underway. the Arecaceae family [palms] sustained the and Potential Use in the Midwest and winds better because of the large number The visualization and underlying Northeast United States.” Gen. Tech. Rep. What was the extent of the damage to the of roots that are secured into the ground, data fill a critical information gap for NRS-148. Newtown Square, PA: US De- trees or forests? Did every neighborhood the flexible spine of the tree, and there are policymakers and managers tasked with partment of Agriculture, Forest Service, lose trees? no branches that are widespread. understanding where overbrowsing has Northern Research Station. 74 p. https:// Our trees here in the CNMI suffered ex- obliterated habitat for young-forest obli- doi.org/12.2737/NRS-GTR-148. tensive damage from Super Typhoon Yutu. How will you proceed with reforestation gate animal species and where regenera- _____. 2018. “Subcontinental-scale The islands of Saipan and Tinian were hit efforts? tion needs to be better managed to restore Patterns of Large-Ungulate Herbivory and with 180-plus-mile-per-hour winds that Our short-term goals are to thoroughly high-canopy species. Opportunities for Synoptic Review of Restoration Manage- almost wiped out everything in their path. assess the damage to our trees throughout further research to better describe rela- ment Implications for Midwestern and Trees with weak root systems fell down or the islands and resupply our nursery with tionships across browse impacts, forest Northeastern Forests.” Gen. Tech. Rep. were uprooted due to the extreme winds beneficial plants and trees for the CNMI. conditions, and regeneration security offer NRS-182. Newtown Square, PA: US De- and flying debris. After the storm, branch- Our nursery and most of our equipment promise for helping to sustain forest val- partment of Agriculture, Forest Service, es were nonexistent, and trunks were and supplies suffered damages from the ues and services. Northern Research Station. 24 pp. snapped off or twisted. Lush, green forests storm. As a result of the damages, we All of the data used in this study are became bare, brown, naked trees. do not have nursery stock available for publicly available from the FIA data por- Most neighborhoods lost a majority the community. We plan to have a plant tal, at tinyurl.com/y78dw6g9. Copies of Letters to the Editor of [their] trees, but some are still standing. giveaway to our community to replace the full report can be ordered by visiting The Forestry lost and/or damaged plants/trees. We will www.nrs.fs.fed.us/pubs/. Agree? Disagree? What was your reaction to seeing the de- continue our mission and duties as CNMI Source welcomes letters to the struction? Forestry. Will McWilliams is a research forester editor. Send letters to Steve I was devastated and speechless upon see- Our long-term goals are to fully re- with Northern Research Station FIA. Wilent at [email protected] or ing the destruction. This was the worst store our forests and plant life in the hopes 10100 Laureate Way, Bethesda, typhoon our islands have encountered. References When I walked outside my home after the Leopold, A., L.K. Sowls, and D.L. MD 20814. 10-plus-hour storm, it was overwhelm- TYPHOON Q Page 13

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