Progress 03/16/15 to 01/31/19
Outputs
Target Audience:The target audience is 2-tiered. The first would be land managers, either the owners or professionals who makedecisions on howsilvicultural practices will be implemented. The second would be within academia, toscientists and also to those who dispense information to the public via extension of other means. The information is comprised with reasonable scientific evidence that planting of highly selected hardwood seedlings in post-harvest conditions can be accomplished successfully. And, at mid-rotational ages, the growth of these trees can be increased with release and fertilization treatments. Withpublication or on-site visits,information is being placed before these audiences and, as with any new scientific devlopment, being adopted as increasingly definitive results rise out of long term, complex and widely-arrayed studies. Changes/Problems:These are long-term studies and provideincreasingly strong results as they progress. What opportunities for training and professional development has the project provided?
Nothing Reported
How have the results been disseminated to communities of interest?Opportunities have included on-site field days for public and professional audiencess, incorporation of the research into formal collgiate coursework, and, with data collections underway, dissemination through scientific publication. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
It is perhaps safe to say among plant communities that are also widely utilized as commodities, hardwoods are essentially the last to be considered for domestication; and while this is not surprising, domesticationis also an inevitability. Hardwoods are comprised of a widely dispersed andcomplex set of species, some similarin terms of how and where they grow;but even with the subtleties of global marketing aside,they are very specific and very sensitive to species:site associations and bound to fail if these are not considered in their management. This wide array of specificrequirements, along with a near universal ability to sprout and retain genetic lineages across several generations, make them hard to work with.However, the domestication of pine, and especially loblolly(Pinus taeda)representedone of the moresuccessfulscientific efforts ever achieved and with it the theoretical groundwork was laid for similar work in hardwoods. And that work is needed, particularly in regeneration systems. The problems and uncertainties in the historicaldependence on natural regeneration in hardwoods, where adequate seed-in-place or an existing understory of desirable sapling-sized trees must be established and counted on, are hard to anticipate and success is difficult to predict. Once a stand full of undesirable trees is up and growing, alternatives to achieve a desirable mature stand can be limited by the species mix. It is a problem that canpersist throughout the life of the stand, often measured in decades.Some very desirable hardwoods, often the oaks (Quercus sp), are declining in regional and national inventories due to the vagaries of certain, increased diseases but also to an inability to successfully regeneratein the presence of an early-successional suite of species, a tree community that is very vigorous and typically predominated by sycamore, sweetgum and yellow-poplar (Platanus occidentalis, Liquidambar styraciflua, Liriodendron tulipfera, resp.). And, unfortunately because of the severity of naturally occuring competition, this is usually more-so true on the best sites.This projectis laying the foundation for domestication of hardwoods,especially the oaks, by successful establishment of seedlings in natural systems where a stand has been removed in a commercial operation and the resulting naturally occurring species mix is predictable only in terms of its competitive vigor, which is generally labelled as being "extremely high." However, its commercial and ecological value is less certain because it is overly occupied with less desirable species. Through a set of grading parameters we have come to understand the increased potential of certain root conformations and seedling size that will allow artificial regeneration to be competitive. An important concept has developed as we recognized the differences between pine plantations and mixed hardwood stands. Thatconcept is to "enrich" a developing stand, i.e., to establish enough predictably competitive seedlings to ensure the mature stand will have anenhanced component. In fact, on large ownerships or at landscape scales,"mixed stands" are desirable. Having an array of species contributes to ecological stability,wildlife values, andaesthetics. Along with that, a "portfolio" of merchantable opportunities gives the ability to respond to markets as they wax and wane, opportunities that might rangefrom cross ties to fine furniture, with sweetgum providing the first and oak the second. The research also is establishing the potential of a subset of the established trees to respond to mid-rotation treatments of release and fertilization, tripling growth in some cases. The core of the project'ssuccess is two-fold: first, artificially establishedoaks are showing free-to-grow tendencies at ages representing reasonable juvenile-to-mature predictions they willoccupythe mature stand, and second, there has been as much as a tripling ofgrowth in mid-rotational oaks where release and fertilization treatments were applied. These two developments, combined, indicate that oaks can be planted on very productive sites following a regeneration harvest, i.e., a clear-cut,a sub-set will enrich the ensuing stand, and the more successful can receive treatments that will increase productivity and decrease rotation length. And, this can be accomplished, and is most soundly accomplished, in the midst of a mixed stand. The study has documented the ability to establish "advance regeneration" by plantingthese pedigreed and highly selected seedling in single tree gaps where increased sunlight has reached the forest floor. This provides a way to establish regeneration in highly layered stands, usually occurring on very productivebottomland sites. A typical silvicultural treament in these stands, stands that are often bereft of hardwoodregeneration,is to kill the midstory to release light to the forest floor in hopes ofdeveloping an understory component with desirable seedlings. The project is showing the potential to follow a partial harvest with planting and releasing the artificially established trees later with a reproduction harvest. Within a mixed stand, every crop tree exists in the midst of a "competition cluster." That surrounding group will have considerable impact on a planted seedling's ability to survive and as it develops its status as a crop tree. For every seedling planted in this study,thecluster has been documented and in time, as the stand develops, there will be ancillary effects within acluster as treatmentsare applied to individual crop trees.Some of thesurrounding trees can be removed and the remaining trees responding as if in a thinning. Even where fertilization is applied to the crop tree, the neighbors can, to some extent, profit. Although these are long-term studies with increasing strength as they continue to develop, results are showing impressive survival rates, growth differences among species, and with these pedigreed seedlings, differences that are tending toward significance as the trees age. The concept of "enrichment plantings"is novel and presents a new way to evaluate plantings by giving weight to the best performers as opposed to averages derived across the entire study. For example, in a particular study where 200 trees per acre are planted, the average height across all trees at yeartenmight be tenfeet and the surrounding competition 25 feet. However, the best 25% of the planted trees might also average 25 feet, or better, and that subset of the original planting are now considered as free-to-grow trees (if the crown grading system, based on a 1-to-28 score, is high enough). These "winners" arecompetitively positioned to indicate probableoccupation in the mature stand. And, 25% of the original 200 would represent 50 trees/acres, well above the 36 trees/acres we have determined to represent a fully enriched stand, indeed, 36 mature oak would predominate an acre.The study is consistently showing results similar to the example, ranging from 20-to-100 free-to-grow trees at an age where juvenile: mature correlations are reasonably high. Even a 20-tree enrichment is not a "failure." For such a long-term investment as a full rotation, 20 high grade oak where none would exist otherwise is a good investment. In several settings where the project's findings have been presented, a general consensus among scientists and professionals, based on comments, has been a perception of this being "new science ... cutting edge ... ora turning over of old assumptions."
Publications
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Progress 10/01/17 to 09/30/18
Outputs
Target Audience:
Nothing Reported
Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?
Nothing Reported
How have the results been disseminated to communities of interest?Forestry students in the Fall Block, Silviculture 322 course see the work in its entirety. The Fayette County Forestry Association centered its Annual Meeting around the research poject. What do you plan to do during the next reporting period to accomplish the goals?Alison Shimer, graduate student is scheduled to finish her project and manuscripts should be accomplished or be underway. John Bowers has manuscripts underway.
Impacts
What was accomplished under these goals?
A Graduate Student, John Bowers, accomplished a Master's Thesis in December, 2016, "Crop Tree Enhancement of Green Ash (Fraxinus pennsylvantca) in a West Tennessee Bottomland;" and manuscritps are in process for publication in appropriate journals. Alison Shimer has been extended in her Master's Program to allow completion of her thesis reporting survival and growth of planted hardwoods. In that study eight species were established on small harvest openings, ranging from 1-to-3 acres. Ten years after establishment 75% (3,139) of the trees were alive. Several novel concepts have come from the work, incuding the defintion of successful regeneration defined as "enrichment" of a deloping stand with artificial regeneration but also maintining the economic and ecological values of a mixed stand. The basic goal is centered around having 36 planted trees per acre embeded in the mature, naturally occuring, mixed stand. Plantations are not expected or desired due to a suite of values associated with mixed stands and the unanticipated risks that can particularly focus on pure stands, with the emerald ash borer being a prime example. Along these lines, this project's developent suggests that research results presenting averages for all planted trees may be misleading when the top half or even just the top quarter of the planted population can be expected to occupy the mature canopy. In simple terms, prediciton of success is based on the "winners," i.e., the successful early-rotation competitors, defined with quantifiable criteria, and most likely and also in general desirably composed of a subset of all planted trees.
Publications
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Progress 10/01/16 to 09/30/17
Outputs
Target Audience:
Nothing Reported
Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?
Nothing Reported
How have the results been disseminated to communities of interest?A presentation was made at the Oak Symposium in Knoxville Tennessee, October 23-26, 2017. More than 150 land managers and scientists were in attendance and were able to hear the results of the project. A unique outcome from the meeting, beyond reporting the new concepts involved in this research, was the idea successfully planted stock can increase the agility needed for research designed to anticipate the biological and management adaptations required to deal with climate change. What do you plan to do during the next reporting period to accomplish the goals?Alison Shimer, graduate student is scheduled to finish her project and manuscripts should be accomplished or be underway.
Impacts
What was accomplished under these goals?
A Graduate Student, John Bowers, accomplished a Master's Thesis in December, 2016. The work reported treatment response in a 30-year-old clearcut where green ash was primarily chosen for crop trees and received fertilization or release treatments. The research indicated significant growth gains and determined the point classification system developed by Meadows et. al. to be an important indicator for individual tree response potential. The research determined co-dominant trees are the most likely to respond to treatments. Additionally, soil analysis collect around each of 375 crop trees and primarily centered on mottling in the surface horizons indicated green ash grew best on the drier sites (mottling below 24 inches), but also these slightly drier sites supported a species mix that was somewhat less competitive and less adapted to these sites. Manuscripts are underway. Alison Shimer, a Master's Student, is near completion of a thesis reporting survival and growth of planted hardwoods, eight species, on small harvest openings that range from 1-to-3 acres. The study was established with 4,190 seedlings in 2006 and 2007. Ten years later 75% (3,139) were alive. Several primary results are apparent, including: sufficient free-to-grow crop trees are available to project mature correlations for a significantly enriched mature stand and as the plantings are maturing an increasing percentage of planted trees are reaching a free-to-grow status, exhibiting a negative-positive growth pattern where, for whatever reason, some planted trees stop growth and begin again as something happens inside their competition cluster to release them or the trees simply renew growth after building below-ground resources.
Publications
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Progress 03/16/15 to 09/30/15
Outputs
Target Audience: The target audience for research output has been natural resource managers, timber consultants, forest conservationists, private landowners, biologists and those who design forest policy. Tour and research overview: regional landowners and professional foresters on-site with 55 people attending. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?A University of Tennessee, extension program was conducted on-site with 55 professional foresters and landowners in attendance. How have the results been disseminated to communities of interest?Tour and research overview: regional landowners and professional foresters on-site with 55 people attending. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
The research is centered on developing high quality hardwood stands with the enrichment of natural regeneration in small harvested openings with the addition of high quality seedlings and the improvement of growth during intermediate stages using fertilization and release. With attention to harvest, regeneration and intermediate stages, the work will develop a silvicultural set of treatments that can be alpplied over the lifetime of a hardwood forest. A large number of group selection openings of 1-to-3 acres have been established over the past 10 years in various portions of the Ames Plantation Forest. These openings have been planted with highly selected hardwood seedlings, primarily several oak species, but also including walnut. Seedlings are planted on a wide spacing, often 20'X20', with a goal of having a subset persist into the upper canopy. If as few as 25% of the planted stock are in a free-to-grow situation at the end of 6 years it can indicate eventual success because 25 large oak at maturity can dominate an acre. On many of these sites and representative of many harvested openings, including clearcuts, oak is often missing in the natural regeneration unless it was established as advance regeneration. A Masters project was begun in 2015 to evaluate survival and growth of the planted trees in harvested openings on 9 bottomland sites. Across all sites, 4,191 seedlings composed if 7 oak species and black walnut from 88 genetic families were established in an incomplete block design. Six sites were planted in 2006 and 3 in 2007. Measurements conducted in 2013 found tree averages on some sites ranging upwards of 5 meters. These 9 sites will form the basis for the Master's project. In all there are more than 20,000 trees in the precision research. Another Masters project was initiated on a Crop Tree Enhancement project composed of 375 green ash trees resulting from a clearcut conducted in 1980. At 14-years-of-age the resulting stand was assessed for viable crop trees and due to an unusual component of green ash, the project was focused on the response of this species to release, fertilization and a combination of the two treatments. The Masters project will examine growth response, and additionally will provide insight into which segment of the crop tree population is most viable for treatment response. Field measurements were completed in the summer of 2015, including a soil sample taken around every tree. Preliminary analyses suggest the lower third, based on initial measurements, of crop trees were unable to respond adequately to treatments. The upper third did not appreciably respond. However, the middle third responded to treatments and improved their relative stature in the stand, indicating there is a target condition within these stands where treatments can be most effectively applied. The crop tree work extends over several sites and several species. As means come available, we will examine these species for similar trends. Some crop tree studies are being evaluated for a repetition of treatments. A Masters study completed in 2002 indicated as much as a tripling of growth with release and fertilization treatments and the significant response holding for 40 years beyond application.
Publications
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2015
Citation:
Bowers, J.L., Clatterbuck, W., Houston, A.E., Zobel, J., Tyler, D. (2015, November). The Impact of Pre-Treatment Diameter on the Growth of Green Ash Crop Trees in a West TN Hardwood Bottom. Poster presented at the 2015 Society of American Foresters National Convention, Baton Rouge, LA.
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