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The Tale of a QDM Club by Dave Edwards
Own Your Own by Virgil Peritts
What Is TSI? by Matt Ross, QDMA
Native vs. Non-Native by Gabriel Karns, M. Colter Chitwood, Chris Moorman, and Dr. Chris DePerno
Oaks For Bucks by Chris Moorman
Deer Season: A Time For Kids by Stephanie Mallory
The Need For Minerals by Brian Murphy, QDMA
Perlitz Ranch Hosts Youth Camp by Kelly Haydel
Timing the Rut With Fawns by Gabriel Karns, M. Colter Chitwood
Ecological Reasons For Hunting by Dr. R. Larry Marchinton and Dr. Karl V. Miller
What percentage of a buck's antler development potential comes from the doe's genes? by Realtree Whitetail Team
Where were the bucks? by Team Realtree
Growths on Deer? by Team Realtree
How Many Teats? by Team Realtree
Why No Oaks? by Team Realtree
Special thanks to:
Quality Deer
Management Association
Land Management
What Is TSI?
Most seasoned deer managers wouldn’t even consider planting a crop of soybeans or brassicas without taking every possible measurement and precaution to ensure maximum nutrient uptake and forage production. Chores such as properly calibrating your seeding rate, applying fertilizer at the most opportune times and eradicating competing weeds are obvious steps towards achieving food plot bliss. But have you ever considered managing your forest in the same manner?
A forest is like any other food plot or agricultural crop – it needs care and maintenance during its lifetime to produce a high-quality product. When a new stand of trees is first established, 4,000 or more seedlings may be found growing on a single acre. Now, fast forward 150 to 200 years. Nature will eventually thin this same 1-acre stand over and over again to fewer than 100 healthy, mature trees; however, wouldn’t it be great if you could shave 50 years off that time-table? Wouldn’t it be great if you could reap the financial benefits of your timber much quicker and maximize acorn or browse production sooner? Sure it would. Enter the forester’s tool to make all that happen: Timber Stand Improvement, otherwise known as TSI.
What exactly is TSI? TSI encompasses several different forestry techniques and was actually first coined to describe any woodland operation that aimed to improve general forest condition but yielded no forest product or revenue. However, today the term “TSI” is often used more loosely, even by foresters and industry professionals. It’s equally common to hear or read about methods described as TSI that may or may not produce timber products and revenue, as long as forest stand improvement is the eventual goal. This is partly related to an improvement in the marketing and utilization of low-grade forest products over the past few decades, which has created new opportunities for landowners to realize financial benefits from trees that previously were of little value.
In addition, because habitat and forest management techniques vary regionally, the term TSI has also informally come to mean different things depending on where your deer camp is located. In the northeast, for example, TSI is often accomplished by pruning a future sawlog tree, leading some northern land managers to use the terms “TSI” and “pruning” interchangeably - although their two meanings are not synonymous. The same holds true for other areas of the country where methods like prescribed burning or girdling may be known locally as “TSI”. As a result, it’s understandable why professional and regional ambiguity surrounding the use of the term TSI has become confusing to some, including amateur deer and habitat managers.
Many treatments classified under “TSI” are actually designed to be implemented on a particular tree size or age class, and applications effectively range from seedlings, saplings, pole-sized timber, and sometimes on even larger trees (See “Classifying Trees by Size” on this page). At some scale, each of these TSI operations can create one or more types of commercial by-products (such as wood chips, firewood, pulpwood, or sawlogs). So, for the purposes of this article and those practicing QDM, let’s just assume that TSI can be applied to pre-commercial or commercial stands of trees, and that the landowner may benefit from forest products and/or revenue. Utilization of those products will depend on the local market and the tree cutter’s capabilities.
Most TSI techniques are defined by the removal or killing of unwanted trees to favor desirable ones, the ultimate goal being quality over quantity. Sounds familiar, doesn’t it? The choices of which trees to remove and which ones to keep will greatly depend on forest stand composition and your objectives. The great thing is that there are many TSI options available to forest landowners. Some may strictly use a TSI program to increase their forest’s value for timber products. Others may perform TSI to improve water quality, forage and cover for wildlife, aesthetics, or even for special products. Fortunately, when a landowner performs work to benefit one of these primary uses, they also reap the benefits in other areas as well.
Because TSI applications can be fairly simple to reasonably complex, seeking out professional advice is typically required to guarantee proper execution. Thoughtful planning will help you meet your objectives sooner and avoid costly mistakes. Contact your state forester to get started. They will first help you make an informed decision whether TSI is a viable option. Forestry consultants are also available to help determine your forests’ potential and will help you develop and carry out a suitable plan.
Treatments: TSI in Seedling or Sapling Stage When TSI is performed very early in the life of a stand it is referred to as a release operation. Release cuts are designed to free desirable seedlings or saplings from the competition of undesirable trees that threaten to suppress them. There are three types of release operations: cleaning, weeding, and liberation cutting. There is only a slight distinction between the first two methods, although both would be applied to a uniform stand of very young trees, such as trees in a 10-year-old clear-cut. A cleaning operation attempts to control both the species composition and quality of a young forest stand by removing less-favorable or less-valuable tree species and trees of poorer form. Weeding operations only manipulate species composition and ignore tree form.
When managing pure seedling or sapling stands through either cleaning or weeding, the first step is to identify which trees you would want to keep. Tree selection will be based on tree spacing, tree form and/or your species preference. Obviously, if you are managing for deer, you may choose to favor one or more tree species that will eventually provide some type of hard mast or other food source in the future. This would be accomplished through a weeding operation.
Proper spacing of favorable trees will vary depending on the species, purpose of management and the site quality. Generally, wider spacing may be necessary to encourage larger nut-bearing crowns and more understory growth if wildlife food and cover are required. Tighter spacing is important to keep younger stands fairly dense in order to promote self-pruning for future timber quality and protection from windfall. Have your forester help you determine the proper spacing of your trees to meet your objectives.
Choosing to retain trees based on form at such a young age will somewhat be determined from the root origin. Seedlings, seedling sprouts, and sprouts growing from stumps 4 inches or less in diameter should be favored over others as these are most likely to grow into trees of good form and timber quality. Sprouts from larger stumps may be retained if they originate very low on the stump or if the parent stump wound is small. Trees that grow from high on a stump can develop butt rot or break off over time. Because many hardwoods readily stump sprout after being cut, it’s also fairly common to find trees with multiple stems when performing a cleaning operation. Multi-stemmed saplings can develop into high quality timber if they are treated when they are less than 20 years old or 3 inches DBH; and it’s best to select trees that have a U-shaped connection (wide enough to place your foot between the stems) rather than those that have a V-shaped connection at the base.
Finally, a liberation cutting differs from both the cleaning and weeding treatments in that the trees removed are actually older and overtopping the seedling or sapling stand. The goal with this operation is to “liberate” the sapling crop of trees that may have greater overall potential than the older age-class. Removing the overtopping trees allows more light, moisture and nutrients to reach the favored, younger trees below.
Treatments: TSI in Pole-sized or Larger Stands Several TSI treatments exist for trees that are pole-sized or larger. These include improvement cutting, thinning, cull tree removal, and pruning. Improvement cutting is typically prescribed when the stand has received no previous forest management, poor forest management or has been heavily grazed. The principles are very similar to a cleaning operation in that the primary goal is to regulate species composition and tree form, except that the improvement cut is applied to pole-sized or larger trees. Trees removed in an improvement cut are usually of poor form, quality, and vigor or are undesirable species.
Thinning is similar to improvement cutting but it tends to be more financially motivated. Specifically, thinning removes trees that would naturally die from suppression or crowding. This increases the total amount of timber recovered over the life of the stand, and it improves stand productivity by increasing the growth rate of the remaining trees. The amount of wood any forest stand can produce in a year is essentially a fixed number that is determined by the growing conditions of the site, such as soil depth, moisture and fertility. When suppressed and crowded trees are removed, sunlight, water, and nutrients that went into growing these trees are redirected to the most vigorous and valuable trees in the stand. So, while thinning operations won’t increase the total amount of wood volume produced on a site, they can increase the proportion of the wood volume that grows as valuable timber.
There are three distinct methods of performing thinning operations: low, crown, and geometric. The first two methods obtain tree selection based on the developmental status of the tree and its position within the crown canopy structure (see the diagram on this page). Low thinnings concentrate tree removal on the lower crown classes. This type of management strategy is an attempt to accelerate the process of natural mortality of suppressed trees that occurs during normal stand development. By removing the lower crown classes, the remaining canopy trees should benefit from a reduction in root competition and experience a slight increase in nutrient flow.
Crown thinnings focus tree removal on the upper crown classes, and are considered to be more effective than low thinnings. Desirable trees are first identified based on their dominance in the canopy, and they can be retained for either timber or wildlife value. These are often referred to as crop trees. A well-planned crown thinning will then remove competitors from at least three out of the four sides of the selected crop trees (within 10-15 feet of the crown tips), which creates growing room. With more sunlight and less competition, crop trees will experience a rapid increase in growth and mast production.
Crown thinnings can be applied uniformly throughout an entire stand to maximize timber volume and browse production or they can be concentrated very specifically on a limited number of crop trees within that stand. To do this, simply determine which trees will be retained as crop trees (such as white oaks), and crown thin only around those individuals. This is called crop tree management. Crop tree management is ideal for the small landowner that wants to stimulate growth and nut production as much as possible with the least amount of cutting. In most cases, crop trees will benefit from being “freed” anytime after the age of 15 years and each should be located about 25 feet apart (50-75 crop trees per acre). If creating adequate deer cover is a major goal, applying a crown thinning across the entire stand may make more sense than managing solely for crop trees.
In geometric thinning, also sometimes called mechanical thinning, tree selection is based mainly on tree spacing or arrangement and is often applied to tree plantations. Common methods of geometric thinning include row, strip or spacing thinnings. Refer back to the June 2004 issue of Quality Whitetails for more on the principles of intermediate geometric thinning operations (“The Big Picture: Managing Midrotation Stands”).
A different TSI treatment for pole-sized or larger trees involves focusing on the poor-quality trees in a stand rather than crop trees. This technique is sometimes called a cull tree removal and it’s designed to make growing space available on areas occupied by deformed, defective, and undesirable trees. Cull trees are defined as any tree, hardwood or softwood, whose quality is so poor that little, if any, income can be made by removing it. Cull trees continue to grow but do not increase in value, all the while shading desirable trees and possibly harboring insects and/or disease. Some of these poor-quality trees may be used for pulpwood, firewood or wood chips, but most culls must be killed by mechanical or chemical means. Be sure to leave at least three large (6-plus inches DBH) dead cull trees per acre because they provide wildlife feeding, breeding and nesting sites.
Pruning is the one type of TSI treatment that does not involve removing or killing trees; it involves the removal of live or dead limbs for the purpose of preventing knots in future lumber. Like all of the above treatments, pruning should be applied to pole-sized trees, but never to trees larger than trees 8 inches DBH. Pruning should immediately follow, rather than precede, any thinning operation and can be performed on softwoods or selected hardwoods where high-value species such as black walnut, black cherry, ash and oak are grown on good sites. Trees should be pruned to a height of 9, 11, 13, 15, or 17 feet above the ground in order to assure high-quality veneer or sawlogs of 8, 10, 12, 14, and 16 feet in length. No more than 100-150 crop trees per acre should be pruned to be economically justifiable, except in the case of black walnut or black cherry where it is practical to prune even a single tree per acre. Branches should be pruned before they reach 2 inches in diameter. Make sure to not prune limbs larger than 4 inches in diameter; once the branch exceeds this size, the wound will heal too slowly and will leave the tree at risk for disease and insect infestation. As a guideline, do not remove more than one third of the live crown during any pruning operation.
TSI Methods Most of the above TSI treatments (except pruning) can be accomplished by either cutting the less desirable trees down or by killing them in place. A forester can determine which treatment is most appropriate for your land based on your objectives, decide how it should be implemented, and will mark the trees to be removed. In many cases, if the undesirable trees contain useful products, a properly conducted timber sale can accomplish a large amount of the TSI. If a timber sale is not feasible, your forester will then either perform the at-cost TSI work themselves, contract it out to a vendor, or can even leave the grunt work for you to do at your leisure to help defray the cost. Any cost towards TSI should be viewed as an investment in the future of your forest. Federal cost-sharing money is also available in many areas to help reduce any out-of-pocket TSI expense (more on this in an upcoming issue) and your forester can help you apply.
Mechanical TSI control methods Undesirable trees that are not merchantable may be removed or killed by several mechanical means: hinge-cutting, bulldozing, mulching, girdling, or by prescribed burning. The hinge-cutting method has already been covered in the February 2008 issue of Quality Whitetails (“Create Living Thicket Cover by Half-cutting”) and is an excellent way to cull undesirable trees while providing abundant browse and immediate cover for deer. Bulldozing down selected saplings and pole-sized trees can also accomplish these same objectives. If you want to open up the forest by removing the understory and selected undesirable trees for aesthetic reasons, chipping the vegetation in place may be another option. Many land clearing services now exist across the country and some are capable of mulching brush and whole trees up to 15 inches DBH. Equipment varies and cutting heads are made to fit on skid steers, excavators, gradalls, and feller-bunchers.
Girdling, on the other hand, involves killing the tree but leaving it standing upright. By cutting away a ring of bark and cambium completely around the tree, you can effectively block the flow of nutrients between the roots and the crown. Girdling can be accomplished with a chainsaw, an axe or a hatchet. Chainsaw girdles are most successful when two parallel cuts are made 4 to 6 inches apart and at least 1 inch deep, whereas axe or hatchet girdles work best by cutting a wide 1 to 2 inch deep notch around the tree. The required width of the notch will vary (2 to 8 inches wide) depending on the tree diameter. Girdling allows trees to deteriorate gradually, thereby minimizing damage to the stand beneath, and it also creates standing dead trees (called snags) which are used by a variety of wildlife.
Fire is another effective TSI method commonly used for forest improvement and maintenance. If conducted safely and properly, prescribed fire can be used in TSI to control undesirable vegetation, reduce wildfire hazards, prepare sites for tree planting, improve seedling production, enhance forage production and quality, improve wildlife habitat, and control plant diseases.
Chemical TSI Control Methods Chemical applications can also be used instead of, or in combination with, physical removal methods. The two types of chemicals commonly used in TSI are called silvicides and herbicides and each act as a translocation poison, plant hormone or growth regulator, contact poison, or soil sterilant. Chemical application of silvicides and herbicides can be performed by frilling, tree injection, basal spraying, stump treatment, foliar spray and soil application (see the sidebar on this page for details on each).
The biggest advantage of using chemicals for TSI is improved prevention of re-sprouting by hardwoods, vines and shrubs after they have been culled.
Whether or not you decide to employ chemical TSI control methods on your property, the issues surrounding the use of herbicides are complex and should be carefully evaluated on a case-by-case basis. Safety concerns and risk of adjacent die-off, or “flashback”, should be warranted. Either way, be sure to use eye and hand protection during application at all times and to closely follow the manufacturer’s recommendations. Also, many states now require an applicators license to legally handle plant-killing chemicals, so obtain the proper permits before you begin.
TSI Benefits There are a multitude of economic, ecological and wildlife-related benefits associated with TSI. If costs are reasonable and product markets are available, research has shown that both tree volume growth and financial returns will increase with each additional TSI treatment. This is mostly because harvesting costs decrease as the average tree size and quality increases. In fact, depending on the species composition and how early treatments are started in the life of a stand, landowners can benefit from an investment return of anywhere between 7 to 20 percent by implementing practical TSI. With a quicker monetary return, you can then begin to utilize the income from your forest that much sooner to help pay for other deer-related habitat and hunting projects on your property.
TSI can also provide environmental and cultural benefits as well. Because TSI is designed to improve the health and productivity of the forest, many of the above treatments also benefit such things as water quality, forest soils, and aesthetic value. As forest improvement measures are taken, the forest canopy will begin to open up and this will in turn encourage vigorous growth by the remaining tree crowns. Healthy tree crowns provide more shade, which helps maintain moderate water and soil temperatures. Well-maintained trees also produce more organic matter annually. The higher percentage of organic matter found in the forest soil will result in better nutrient retention and water holding capacity.
Wildlife, especially deer, also highly benefit from TSI management. One example is increased fruit production. Trees in a dense stand tend to put most of their energy into vertical growth to obtain sunlight. TSI allows trees to put most of their energy into crown growth. This increase in crown growth should yield higher fruit production for both hard and soft mast species. TSI can even reduce the amount of time it takes a tree to reach maturity, which means your trees will reach optimal fruit production faster. If you don’t end up using the culled saplings and trees removed through TSI for firewood or other timber products, they can then either be strategically piled to direct deer movement throughout your property or left on the forest floor to create or enhance bedding cover.
New forest openings created by TSI will also promote a flush of understory growth. This increase in the forests’ structural diversity will attract a wider variety of wildlife species, and will be particularly attractive to deer. As the canopy of a young stand rises into an older sapling stage, the edible browse will begin to grow out of a deer’s’ reach. Browse can also become shaded out and disappear after closed canopies develop in the overstory. The shrub and seedling growth response to any cutting of the overstory will be directly proportional to the amount of canopy that is removed. So, obviously, if you wish to provide more browsing opportunities for deer, instruct your forester to adjust the TSI prescription accordingly.
TSI is a wonderful management practice for forest landowners that can drastically improve the timber quality and wildlife habitat on your property. Now that you are thoroughly versed in both theoretical and technical information about TSI, use this article as a future reference of the wide variety of forest improvement treatments and methods that are available. Consult with a local forestry professional to determine if any of these TSI techniques are a viable option for your forest.