Profile is a plant growth regulator used by professional arborists and utility foresters for management of tree shoot growth and reduction of biomass. Profile may suppress “dbh” growth, or diameter at breast height, which benefits trees growing in municipal vaults and other confined areas. Profile also offers potential therapy for trees in mild decline.
Profile 2SC tree growth regulator (TGR) is a xylem mobile plant growth regulator that slows vegetative growth by inhibiting gibberelin biosynthesis. Profile 2SC reduces shoot growth thereby reducing the volume of biomass that must be removed from trees when trimming occurs and may extend the trimming cycle. Profile 2SC also may serve as an effective preventive action or rehabilitative treatment for trees growing in stressful conditions.
Much of the energy of a tree is directed into growth, and the rate of growth is directly related to the rate of energy use. Fast growing trees tend to have shorter lives than trees that grow slowly and can allocate more energy away from the canopy.
The active ingredient in Profile 2SC, paclobutrazol, inhibits the biosynthesis of gibberellic acid - the compound responsible for plant cell elongation. As gibberellic acid production decreases, production of other compounds like abscisic acid and chlorophyll increases.
Both abscisic acid and gibberellic acid are produced from the same starting material, thus when gibberellic acid formation is decreased, abscisic acid production increases. Abscisic acid induces responses that protect the tree and help plants withstand and respond to environmental stresses. The effects of increased abscisic acid include stimulation of stomatal guard cell closure and an increase in the defense response of the tree.
The closure of stomata limits water loss from transpiration, maintaining leaf water relations and lowering the risk of scorch and tattering caused by severe leaf dehydration. In addition, the amount of carbon dioxide that enters the leaf is reduced, limiting photosynthetic capacity during optimal conditions. When conditions become stressful, the benefit of improved water relations allows photosynthesis and other metabolic functions to proceed in treated plants while untreated plants shut down.
Chlorophyll molecules are made up of a ring structure with a magnesium atom at the centerending in phytol. When gibberellic acid formation is inhibited, more phytol can be formed and chlorophyll levels can be enhanced, resulting in a darker green leaf.
Carbohydrates produced by photosynthesis support all metabolic processes of life, and allocation of this limited resource is very important. Energy not spent on above ground vegetative growth is allocated to a tree's root system , defensive chemical production and storage for future needs.
Application procedures for current tree growth regulators (TGRs) like Profile 2SC have been simplified but, as with any application, the applicator is the key to success. Proper application of Profile 2SC will ensure even distribution and uptake in the treated tree. In addition, accurate tree identification, measurement and precise dose determination are key to a successful treatment. Without these basic skills, Profile 2SC may be improperly applied, resulting in little or no response or over-regulated trees that may develop small leaves and exhibit little or no growth.
Once a trained and competent applicator is familiar with the process for properly utilizing Profile 2SC, application via soil injection will prove to be a quick and easy, typically three- to five-minute procedure per tree requiring the following simple steps:
Depending on factors such as environmental conditions, the location, number and proximity of trees to be treated and your treatment budget, you can currently choose between two equally effective methods of applying Profile 2SC (the third alternative will be available in the near future);
Each method is covered in detail below. Before applying, however, the correct rate and dosage needs to be determined with tree identification and measurement, location, crown volume, soil type and the tree's final ideal appearance.
Tree Identification and Measurement
It is important that applicators are familiar with the tree species in their region that will be treated. A thorough knowledge of tree identification and aboriculture will help an applicator to determine whether or not a tree can be treated with Profile 2SC and how much of the product is necessary. After an accurate identification and measurement, the Profile 2SC species/rate card will indicate the dosage required for an effective treatment. It is important to note that while treatment of some trees is prohibited by the product label, other tree species may be unlisted but not prohibited. These trees can be treated by using rates for similar species and following all other label directions.
For the purpose of application with Profile 2SC, the diameter of a tree is measured 4 ½-feet above the ground and is termed the "diameter at breast height," or dbh. A proper measurement can be accomplished in a few simple steps. Next, using a dbh tape measure, wrap the tape around the girth of the tree being careful not to twist the tape. Be sure to use the dbh side - not the inches side that would give you a measure of circumference instead of diameter - and start your measurement at the tape index mark to get a correct assessment of the tree's diameter.
A variety of unique situations may arise that will require some measuring ingenuity. For example, be sure to stand on the upslope side of the tree if you're on an incline. If the tree is growing at an angle, measure at a right angle to the lean of the trunk. When swellings, bumps or branches occur at breast height, the diameter should be measured at an equal distance above and below 4 ½ feet and the two measurements averaged. For trees with multiple stems at breast height, add up the measurements of each stem and compare the total to the measurement below the fork. Base the application rate on the lesser dbh measurement. Finally, for a large tree with a dbh greater than those listed on the rate card, simply double the rate for a tree half its size. For example, treat a tree measuring 40 dbh at twice the label rate for a 20-dbh tree.
SePRO's two-sided Profile 2SC rate cards feature mixing instructions on one side and rate guidelines on the other. Rate cards must be customized for particular geographic regions to account for different tree species and soil types. You can get a customized rate card by contacting a SePRO representative. The rate card will help you determine the correct dose based on the tree's species, dbh, location, crown volume, soil type and its final ideal appearance. Once you've established the correct dose, it's time to properly measure and mix the treatment solution. It's important to always shake the container first to ensure that the contents are thoroughly mixed. If you wish to mix a small batch, mix 317 milliliters of Profile 2SC with enough water to produce one gallon of ready-to-use solution. A larger batch of 12 gallons can be produced by mixing one gallon of Profile 2SC with 11 gallons of water.
The addition of a suspension aide to the mixed treatment solution is strongly recommended as it will make applying Profile 2SC even easier. It will reduce hard packing at the bottom of the tank and lessen the amount of agitation required to keep the solution in suspension. A suspension aide is particularly recommended with larger quantities or if the solution may sit for a period of time since the solution with the additive can easily be resuspended by agitation. Add the suspension aide at a rate of ¼- to ½% to half of the total water needed and stir (check the adjuvant label for the proper mixing sequence). Be sure to accurately measure the additive since too much can make the solution too viscous. Add the Profile 2SC and the remaining water. At this point, a ¼% high quality non-ionic organosilicate surfactant may also be added to the solution. It will lower the surface tension of the solution for applications to medium texture and heavy clay soils. This surfactant addition can improve product efficacy, especially in heavier soils as it will aid uptake by spreading the solution further through the soil to the tree's roots.
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