Whether you’re a newbie or a seasoned pro, the fundamentals can’t be overlooked… in all sectors of society. For example, it’s pretty common to see college football teams struggle from one year to the next during coaching transitions—it may be difficult for players to adjust. In most cases, a return to the fundamentals is the best approach.
The same is true in arboriculture. As new tree care workers are trained, steeping them in the fundamentals of sound tree care techniques is a smart, common-sense initiation. It’s wise for journeymen and sage arborists as well.
For experienced employees, a slight variation may be appropriate, along the lines of a thorough set of reminders. As each function is carried out during the work day, a good routine would be for crew leaders to verbalize reminders such as: “Make that pruning cut just outside of the branch collar, not flush with the trunk,” or to ask questions like “OK, now, where are we going to cut this limb?” Short discussions that follow can be very helpful to reinforce previously learned information, especially if newer workers overhear what the veterans are saying. All of this may take a little time, but it’s worth the wait to get it right.
In this “Back to the Basics” focus on learning and reviewing fundamentals, there’s nothing more foundational than Right Tree, Right Place (RTRP). Even first-day-on-the-job workers have seen good implementation and violation of this basic tenet. It’s really quite simple – the idea is to place trees where they have a good chance to not only survive, but also thrive, becoming an asset to the property owner. RTRP is also complex, with several components that must be considered in order to achieve the desired outcomes.
Site analysis: A thorough consideration must be made of the property’s nearby surroundings and unique artifacts, including the slope, soil type, drainage potential, proximity to other plantings, wind patterns, proximity to established turfgrass, irrigation system characteristics and potential microclimates.
Species diversity: Whenever possible, a property should contain no more than 10 percent of any tree species. In short, the more diversity, the better.
Tree function: Choosing the right tree means considering the desired purpose: shade, screening, color, winter interest, edible fruits, etc.
Pest resistance: Many species and cultivars are genetically resistant to pests such as apple scab, fireblight and pine wilt. Choose these whenever possible.
Shade, sun: Sun preference is important in terms of longevity in the landscape. When shade trees are needed, those that are adapted for full sun exposure are best, whereas understory trees require shade and semi-shade suitability.
Location, location, location: Quite simply, there are good locations for trees and bad locations for trees. When adequate soil volume, irrigation potential or sunlight exposure is not available on the property, it’s wise to consider non-tree alternatives.
Start by finding the first or top lateral root. It may be necessary to scrape some soil off the top of the root ball. Placement is important; aim to put the top root even with or slightly above the top of the planting hole.
An often overlooked issue is digging the proper-sized hole. Actually, it’s best to think of the excavated soil as a “planting area.” A good rule of thumb is to size up the root ball and create an opening in the ground no deeper than the root mass, and three times as wide. A wide planting area helps to encourage roots to expand rather than to remain where planted. Also, placing the root ball on top of undisturbed soil in the planting area prevents the root ball from sinking.
The next consideration is the avoidance of girdled roots. In many cases, trees arrive at the planting site in plastic pots or in balls wrapped in burlap, with the outer section of the root system consisting of a mass of encircled underground stems. If left in this arrangement, they will continue to grow larger and larger in diameter, with very few breaking free of this pattern and outwards into the adjacent soil.
To the extent possible, break roots loose from the girdled root mass and spread them laterally in the planting hole. Inevitably during this process, a few roots will break, exposing the inner tissues. As with many other issues, there’s a balance between damaging the roots to break them loose and allowing them to remain in an arrangement that is almost certain to create problems with uptake of water and nutrients and/or create structural weakness. Ideally, all the constricted or encircled roots can be freed and spread laterally in the planting area. The other side of the spectrum is the need to cut through large roots in order to spread them out, an action that should be avoided to deter invasion of root decay organisms.
Another consideration in the avoidance of girdling roots is the matter of enhancing the planting area by adding sand, peat moss, bark, compost or other materials to encourage root growth. Unfortunately, in most cases, these amendments encourage the expanding roots to remain in the planting area instead of growing into undisturbed soil. The effect that is produced is similar to a perched water table. The soil that was removed to create the planting area is best to use as backfill for the new tree or shrub.
Added nutrients at planting time are usually counterproductive as well. Woody roots tend to be stunted as a result of coming into contact with fertilizer in the planting area. If the area is known to be of low fertility, soil testing to determine which nutrients (and in which form) should be added in later years is a good step. Though it may seem obvious, constrictions such as burlap, pressed peat moss, string, cording, etc., should be removed from the root mass. The purpose of these materials is to keep the ball intact until arrival at the planting site. Unfortunately, they also will increase the odds of restricting expansion of the root system.
A good look-see
Regular inspection of the specimens on a property is key to a successful tree care program. Generally, there are two phases to this process – scouting and monitoring. Scouting is usually referred to as an individual act, while monitoring involves inspection over time.
Scouting can be implemented in several ways, but a couple of methods stand out. First, traditional responses to a customer’s inquiry involve a regular or first-time client who calls and asks for a representative of the company to “come out and look at my tree. After the inquiry, a thorough inspection of the tree in question and surroundings is made and a preliminary diagnosis is communicated to the caller. The second is a more proactive approach, where an arborist looks over his notes from the previous year and notices that a treatment was made for a certain disease or insect problem and takes the initiative to schedule an inspection on his own.
Monitoring is best thought of as a series of regular visits to a property for inspection. Often sold as a year-long package, these inspections are made periodically throughout the season, paying attention to the development of specific, historically documented problems as well as new developments that may occur along the way.
IPM and PHC
During scouting, it’s important to look for pests. That said, if a tree is planted and sited according to the guidelines above, pests will generally be few. These are two of the hallmarks of Integrated Pest Management (IPM) and Plant Health Care (PHC) – systems that take all influences of a property and growing environment into account when developing a pest control program.
While most definitions cast IPM as focusing primarily on limiting damage from insects, weeds, diseases, vertebrates and abiotic factors and place PHC in a holistic, cradle-to-grave sense, there is a huge amount of overlap between the two approaches.
Though each can be classically defined and attempts can be made to keep them separate, both can be interpreted, adjusted and implemented for good – and for the ultimate goal of installing and maintaining healthy trees in the landscape for amenity, noise reduction, energy savings and other environmental benefits.
During scouting and monitoring, it’s important to evaluate the general health of the tree, to look for pests and to document the presence of defects such as crossing limbs, decay and bad branch angles. In fact, that’s one of the real benefits of these techniques – to identify these problems in trees before they become worse and put the homeowner at risk of damage to the people who reside in or visit the property, as well as the elements of the property themselves.
Generally, the sooner that these defects can be noted to the property owner, the better. Pruning cuts that are made on limbs that are an inch or less in diameter usually pose little if any potential for decay or cracking to the tree. Larger ones, 6 to 8 inches in size, often cause issues. Certain tree species tend to resist decay (osage orange, black locust, black walnut), while others (silver maple, poplar) usually decay readily within a few years of limb removal.
In addition to paying attention to pests, defects and the general health of the trees on a property, it’s wise to probe the soil and check for compaction during scouting. A simple soil test will give a clue as to how susceptible to compaction this particular site is. A soil probe can be helpful as well; a steady push into the soil in various locations around the tree – drip line, 3 feet out from base, outside the crown – will provide insight into the moisture content, organic matter and other key characteristics of the soil. When soil test results and probing procedures reveal high clay content, compaction is a common result.
When compaction has occurred or is likely to occur, aeration followed by thin application of compost topdressing and/or vertical mulching may be recommended to the property owner. In these situations, these options are best thought of and presented as long-term solutions rather than quick fixes. In severe cases, radial trenching is a third option, an invasive procedure where a rototiller is used to create new channels into the soil under a tree canopy to lessen compaction and encourage new roots to form.
Depending on the amount of fertilizer that is routinely applied to the turfgrass on the site, additional nutrients may be necessary. This is another item to note on the soil test results as well as the pH and organic matter content. Again, when stunted growth or yellow leaves are noted during scouting, fertilization should be at least considered.
Overall, if the tree in question is growing in well-aerated, pH-balanced soil; mulched with organic wood chip materials; roots kept moist, not soggy or dry; well-sited in terms of shade, sun, wind, utilities and other site-specific factors; fertilization should be the occasional practice rather than the norm.