What Is The Best Tree Fertilizer?

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    The chore of fertilising your trees may appear to be a challenging one, but it really doesn't have to be! The market is stocked with a wide variety of different kinds of fertiliser. Which one would be best for you to use? That, of course, is dependant on the species of tree that you intend to plant. This page will assist you in navigating the procedures, as well as explain which are optimal for the various species of trees. Let's get started!

    Because there are many different kinds of fertilisers available, it can be difficult to determine which ones are effective for particular kinds of plants or trees. In addition, in order for a plant to grow correctly and remain healthy, it need a specific amount of each nutrient in a specific ratio. Some plants require more nitrogen, while others require more phosphorus than others. How exactly does one determine which plant requires what kind of fertiliser and how to apply it?

    Garden trees, particularly those that are native to the area, require care and attention to ensure their continued health and safety. When compared to the same species living in the bush, a tree that is living in your garden is subject to a significant amount of stress. Worrying about tree removal? Then, Tree Amigos tree removal solution  is the right choice!

    He illustrated this point by pointing out the striking similarity between a massive blue gum (Eucalyptus saligna) growth in a residential backyard and the same tree in the surrounding bush.

    Since the home was constructed, soil has been piled up on top of the roots of the tree that is located in the backyard. A cement slab and an incinerator were located nearby. In addition to this, there was grass being grown close to the tree, which would be in competition with the tree's root system for the nutrients that are available. In addition, the lawn was raked on a consistent basis to remove dead leaves, bark, and twigs.

    When compared to the amount of natural run-off the tree would have received before the region was subdivided and residences were built, the tree now receives less water as a result of the houses, roads, and footpaths that are located in its immediate vicinity.

    In contrast, the tree that was growing in the unbroken wilderness had a thick layer of leaf mulch that had accumulated around its trunk and roots. This mulch not only helps to feed the tree, but it also nourishes the microorganisms that live in the soil. The soil levels in the bush had not been disturbed, and it appeared that the tree was in good health and strength.

    A closer inspection of the tree in the backyard revealed that it was suffering from stress. Additionally, there were signs of a bullseye borer in the primary trunk of the tree (caused by the larvae of one of the longicorn beetles).

    An attack by a borer is unmistakable evidence that the tree is under stress because a healthy tree would be able to fend off such an assault. Holes in the trunk or branches (particularly holes that look like a bullseye), seeping gum, a buildup of frass or fine wood shavings, and dieback of branches are some of the signs that you should watch for in your tree.

    Fertilising Trees & Shrubs

    Plants that are alive, such as trees and bushes, are considered investments since their worth increases with time. It is reasonable to anticipate trees and shrubs to flourish with the appropriate level of care, which may include watering, fertilising, and pruning in addition to correct selection and planting. Mature trees and shrubs that are growing in an environment with favourable soil conditions may require very little or no fertiliser at all. This is similar to the way that certain drought-resistant plants that have been established may not need water during dry spells.

    Misinformation and improper use of fertiliser are common occurrences. Fertilizer is not the same thing as "food." Through a process called photosynthesis, plants are able to manufacture their own sustenance in the form of sugars. The minerals and nutrients that are provided by the fertiliser are the components that are essential for the process of photosynthesis, which is necessary for growth. Fertilizer can be given to the soil in order to maintain an appropriate supply of minerals in situations where the soil does not contain them.

    It is not appropriate to think of the fertiliser as a treatment for sick plants in situations where inappropriate or unhealthy plants were selected, haphazardly planted, or inappropriately watered.

    When fertilising trees and shrubs, it is important to keep in mind the following two points: (1) Fertilizer is helpful when it is required; nevertheless, (2) It must be applied in the appropriate quantity, at the appropriate time, and in the appropriate location.

    Establish A Need For Fertilising

    The care of the gum tree in the backyard needed to be attended to right away. It was of the utmost importance to treat the ailing roots and provide an environment in which the microorganism population in the soil might recover. If this is accomplished, the tree will begin to grow again, and ideally it will be better able to withstand the insect attack.

    In order to accomplish this, the tree was sprayed with a substance known as Seasol. It has been demonstrated through research that using this particular product can assist in revitalising the roots. This may be achieved by stimulating the expansion of beneficial soil microorganisms, notably mycorrhizal fungi, which are typically connected with the root system of trees.

    When microorganisms in the soil are present, they make it easier for the tree roots to receive the nutrients necessary for growth (including phosphorus, zinc, manganese and copper).

    It is recommended that the Seasol be applied on a consistent basis for a number of months prior to the application of any fertiliser. Application of chemical fertiliser in its purest form can be harmful to microorganisms and make the situation even more severe. Don recommends using an organic fertiliser such as Dynamic Lifter or blood and bone once the tree has begun to respond to the treatment with Seasol. This type of fertiliser will not have a negative impact on the newly developing population of soil organisms.

    As an alternative method, he suggests making use of slow-release tree tablets. These tablets supply nutrients to a localised region, which is just where the tree requires them. Sulfate of ammonia and complete lawn food are two practises that are frowned upon and ought to be avoided at all costs.

    To assist you in determining whether or not you should apply fertiliser to your trees and shrubs, take the following factors into consideration:

    Test Your Soil You should have the Clemson Extension Service test the quality of your soil. The amount of acidity or alkalinity (pH) of the soil, as well as the levels of the various nutrients that are present, can be determined by the use of a soil test. Depending on the findings, you might need to add nutrients to the soil in order to compensate for any deficits that you find there.

    Check shrubs and trees for the following indicators of poor development: leaves with an abnormal coloration (pale green to yellow), less than normal leaf size, earlier than normal fall coloration and leaf loss, little yearly twig growth, or twig or branch dieback.

    You shouldn't automatically think that adding fertiliser will fix these issues because these signs of poor growth aren't necessarily related to low levels of nutrients in the soil, and you also shouldn't assume that adding fertiliser will cure these issues. These symptoms can be brought on by a variety of factors, such as a soil that has been overly compacted; stressors brought on by pests, diseases, and weeds; or severe weather conditions. Find out what's causing the issue and make sure it's fixed before you start fertilising.

    Age at Planting: Fertilizer applications made during the first few years of an established tree or shrub's life after being transplanted can hasten its top development and assist young trees in filling the area in the landscape that is given to them. Recent plantings of trees and shrubs benefit greatly from the use of slow-release fertilisers.

    There is no need to fertilise shrubs or trees that are growing in a lawn that is fertilised on a routine basis because doing so would be unnecessary. A portion of the fert

    iliser that is spread on the grass will be taken up by the roots of the nearby trees and bushes. On the other hand, trees and shrubs growing in planting beds may require fertilisation, particularly on sandy soils that contain a little or nonexistent amount of organic matter.

    Commonly Applied Nutrients


    Nitrogen (N), phosphorus (P), and potassium are the three nutrients that are utilised the most frequently (K). Calcium, magnesium, and sulphur are three other nutrients that are important to plants and are utilised in substantial amounts. However, because magnesium and sulphur levels in soils in South Carolina are typically adequate, it is typically unnecessary to apply either of these nutrients.

    Micronutrients like zinc and iron are frequently used in various types of fertilisers. If your shrub or tree is suffering from a micronutrient shortage, you should either use a fertiliser that contains the micronutrient that is lacking in the soil or apply the required amount of the nutrient that is lacking in the soil.

    Frequently Asked Questions About Tree Fertilizer

    Applying fertiliser to a tree is not as daunting a task as one might think. The most important part is to choose the right fertiliser for the tree. Once that has been determined, the application process is relatively simple.

    First, identify the tree's drip line- this is where rainwater drips off the leaves. Next, use a shovel or tiller to loosen the top layer of soil along the drip line. Finally, spread the fertiliser evenly and water it well. With a little care and attention, fertilising a tree can help it stay healthy and thrive for many years.

    Fertiliser is any material added to the soil to provide plant nutrients. These nutrients can come from a variety of sources, including compost, manure, and minerals.

    Fertilisers are often used to improve the yield of crops, but they can also be used to improve the health of lawns and gardens. When choosing a fertiliser, it is important to consider the needs of the plants that will be grown in the garden. 

    For example, some plants may require more nitrogen than others. Once the right fertiliser has been selected, it is important to follow the instructions on the package to ensure that the plants receive the correct amount of nutrients. Over-fertilizing can lead to problems such as burned roots and yellow leaves, so it is important to be careful when using this product.

    Fertilisers are an important tool for gardeners and farmers alike. They provide essential nutrients that plants need in order to grow strong and healthy. Without these nutrients, plants would be stunted, yellow, and more susceptible to disease.

    Fertilisers come in many forms, including manure, compost, and chemical solutions. Manure and compost are made from organic matter, such as leaves and food scraps. 

    These materials break down over time, releasing nutrients into the soil that plants can absorb through their roots. Chemical fertilisers are made from inorganic compounds, such as nitrogen, phosphorus, and potassium.

    These elements are often found in abundance in the environment, but they can be unavailable to plants due to soil conditions or other factors. By applying fertilisers to the soil, gardeners can ensure that their plants have the nutrients they need to thrive.

    Fertilising your garden plants is a great way to give them the nutrients they need to thrive. But with all the different types and formulations of fertiliser available, it can be difficult to know which one to use.

    The first step is to determine the needs of your plants. For example, some plants prefer high levels of nitrogen, while others need more phosphorus or potassium. 

    Once you know the specific nutrients your plants need, you can select a fertiliser with the right proportions. You can also consult a gardening expert or ask your local nursery for advice on which fertiliser to use. With a little research, you can easily find the perfect fertiliser for your garden plants.

    Fertilisers are a critical component of successful gardening, providing plants with the nutrients they need to thrive. There are many different types of fertiliser available, each designed to provide a specific benefit. For example, nitrogen-rich fertilisers are often used to encourage leafy growth, while phosphorus-based products help to promote blooming. 

    Fertilisers can be applied in several different ways, including directly to the soil or through the plant leaves. In general, it is best to follow the instructions on the fertiliser label to ensure that you are using the product correctly. With proper care, fertilisers can help your plants grow stronger and healthier, yielding bountiful harvests season after season.

    Kind Of Fertiliser To Use

    The use of a complete fertiliser such as 16-4-8, 12-6-6, or 12-4-8 is typically advised, unless the results of the soil test indicate that sufficient levels of phosphorus and potassium already exist.

    There are two different types of fertilisers available: quick-release and extended-release. Fertilisers with a rapid release of nitrogen, also known as water-soluble fertilisers, are more cost-effective than slow-release fertilisers, which gradually release nitrogen over a longer period of time. On the other hand, the nutrients contained in a fast-release fertiliser may be quickly removed from the soil.

    After only a few inches of rainfall or irrigation, the soluble fertiliser may pass past the root system in sandy soils that have good drainage. This may occur in soils that are well-drained. Leaching will occur more slowly in clay soils because of the finer structure, although runoff could be higher.

    When compared to fast-release fertilisers, which have nitrogen that is water-soluble and rapidly available to the plants, slow- or controlled-release fertilisers have longer periods during which the nitrogen is released. Sulfur can be used to coat the nitrogen in slow-release fertilisers, or the nitrogen can be present in another form, such as IBDU or urea-formaldehyde.

    The "water-insoluble" or slow-release nitrogen component of controlled-release fertilisers should make up at least half of the total amount of nitrogen contained in the product. The use of slow-release fertilisers is recommended in situations where there is a high risk of runoff, such as on slopes or in regions with compacted soil. This type of fertiliser is also an excellent choice for newly planted bushes and trees. Because the nutrients are released gradually, there is a reduced risk of damage to the fertiliser (also known as "burning") and water contamination.

    Nitrogen and other nutrients can be gradually supplied by using natural fertilisers such as sewage sludge that has been composted, cow manure, or full fertiliser mixes. These natural "nutrient providers" offer a number of benefits, one of which is the provision of trace elements, which are minerals required in only very small quantities, such as iron or zinc, and which are typically absent from synthetic fertilisers. The structure of the soil is also improved by natural fertilisers.

    The content of nitrogen, phosphorous, and potassium in natural fertilisers is often lower, which is one of the disadvantages of using natural fertilisers. As a result, a greater quantity of a natural fertiliser needs to be applied in order to provide the same amount of nutrients that can be obtained with a lesser quantity from a synthetic nutrient source. This is because the natural fertiliser contains more of the nutrients that the synthetic nutrient source does.

    There is a wide variety of fertiliser that may be used on grasses found in lawns. Some fertilisers, commonly referred to as "weed-and-feed" fertilisers, could contain a herbicide that is harmful to groundcovers, vines, shrubs, and trees. Always make sure to read the warning labels and follow the instructions precisely.

    Amount Of Fertiliser To Apply

    Fertiliser treatments for lawns (HGIC 1201, Fertilizing Lawns) are based on real pounds of nitrogen, just like the rates advised for fertilising shrubs and trees (HGIC 1201, Fertilising Shrubs and Trees). It is possible to provide bushes and trees between two and four pounds of real nitrogen per one thousand square feet of root spread area annually.

    The area occupied by the root spread is 1.15 times that of the crown spread (3.14 times the radius2; see Figure 1 for an illustration of this). As a result, in most cases, younger shrubs and trees ought to be given higher concentrations of nitrogen than mature plants. See our list of available arborist services Perth  for your tree removal solutions.

    When fertilising shrubs and trees found in lawns, be sure to follow the rate and timing recommendations provided for the turfgrass. Applications that contain more than 2 pounds of real nitrogen may either overstimulate the grass or cause it to catch fire, depending on the composition.

    If trees or shrubs growing on fertilised lawns display symptoms of nutrient deficiency suggesting a need for additional fertiliser, space the applications of fertiliser a few months apart, making sure not to exceed the total annual quantity of nitrogen required by your lawn grass (follow the rate and timing for the lawn grass).

    It is important to refrain from adding an excessive amount of fertiliser as this can be detrimental to both the plant and the environment. An excessive amount of fertiliser results in growth that is stale, feeble, and brittle. It is also more susceptible to damage from factors such as cold, drought, and pests. In addition, any fertiliser that is not taken up by the plant's roots has the potential to contaminate both the groundwater and the surface water.

    They suggests attentively observing the dosing directions printed on the product's label. He added one cup of Seasol to a watering can that had a regular capacity of nine litres (250ml to 10 litres of water). He then used this liquid to fill each of the holes created by the forks and suggested that the therapy be carried out once per month for the next six months.

    Applying granular fertiliser or tree tablets at the rates specified on the packet, which will depend on the size of the tree, should be done once the tree has begun to grow, which normally occurs after two to three months. As a guide:

    • Up to five meter-tall trees (small trees ) — One kilogramme of fertiliser
    • For trees between 5 and 10 metres tall, use between 2 and 5 kilogrammes of fertiliser.
    • Trees over 10m (tall trees) - Five to ten kilogrammes of fertiliser

    A hole should be dug into the earth, and the tree tablets or granular fertiliser should be placed into the hole. It is necessary for the hole to be significantly bigger than the forked holes. Don suggests using a crowbar to create a hole that is around 25 centimetres deep. In addition to this, holes should be dug underneath the rocks and pathways that are in the root zone.

    Backfill the space after the tablet has been positioned in the hole. In addition to the typical doses of fertiliser, the tree should also receive a thorough soaking once a week during the warm months and approximately once every three weeks during the colder months. You should get in touch with a certified tree surgeon if you have any questions regarding the well-being or the security of a large tree in your garden.

    Fertiliser Application Methods

    Both indirect and direct approaches can be utilised in the fertilisation of plants. Fertilizer should be spread across the entire root zone region using one of the two methods. Because of the naturally high oxygen concentrations at the soil surface, the primary feeding roots of a plant are often found within the top 10 to 14 inches of soil. This is because the oxygen concentrations near the soil surface are higher.

    As a result, many of the roots of the plants that are mulched are situated directly beneath the mulch on the surface of the soil. Spread mulch or fertiliser over the top of the soil; the water from precipitation or irrigation will transport it down to the plant's roots.

    Irrigate the plant as soon as possible after applying fertilisers, regardless of the type of fertiliser or method of application you select, in order to remove any fertiliser that may have accumulated on the leaves, as well as to assist nutrients in dissolving and penetrating through the mulch and soil to reach the roots. A portion of the nitrogen that is applied may be lost to the atmosphere due to evaporation if there is insufficient irrigation or rainfall. This would be to the detriment of the plants.

    Indirect Fertilization: When the property as a whole is fertilised, the shrubs and trees that are growing in the lawns are indirectly fertilised as well.

    Direct Fertilization: Spreading the fertiliser over a wide area is both the most cost-effective and economical way to directly fertilise trees and shrubs. Spread the recommended amount of fertiliser across the entire root zone using either a cyclone or drop-type spreader. Cut the total amount of fertiliser that has to be applied in half in order to have the best coverage possible.

    To achieve optimal coverage, begin by applying one-half of the total quantity in one direction, and then proceed to apply the other half in a direction that is perpendicular to the first. When fertilising over the top of shrubs and groundcovers, make sure the leaves are dry before applying the fertiliser. After application, use a leaf rake or broom to sweep the fertiliser off the leaves and onto the ground below. It's possible for certain plants, including liriope and azaleas, to sustain damage if they allow fertiliser grains to accumulate in the whorls of their leaves.

    If the soil in a lawn has become compacted, it should first be aerated, and then it should be fertilised. If you water the fertiliser in after you've applied it, you'll lessen the likelihood that you'll hurt any groundcover or lawn grasses. The leaves of bushes and trees can have liquid fertiliser brushed on them to improve their health. It is usual practise to employ liquid application in the treatment of micronutrient deficiencies in azaleas, such as iron chlorosis or yellowing (the youngest leaves are yellow leaves with green veins).

    Foliar applications offer a temporary solution that can manage deficits in the leaves that are already present; nevertheless, the best benefits are typically attained in the spring. However, applying fertiliser to the leaves will not remedy the root cause of the micronutrient shortage, which may be due to an imbalance in the pH of the soil. Refer to the soil test in order to discover the cause of the problem. In the event that the pH cannot be balanced, it will be necessary to apply the foliar treatment a second time.

    In addition, the irrigation water may contain a fertiliser that is in the form of a liquid, dissolved dry formulation, or both. By engaging in this technique, nutrients will be added to the upper soil surface, which is where the majority of the roots capable of absorption are found. Take special precautions to provide an uniform covering and achieve the ideal dilution rate. It is recommended that a device that prevents backflow be installed on the irrigation system.

    When To Apply

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    When plants require fertiliser and when they are able to readily absorb nutrients through their roots, fertiliser should be applied. Your application should be timed so that it coincides with periods of active root growth and sufficient soil moisture. Fertilizer should be applied to trees and shrubs in the early spring, and if the conditions are favourable for plant growth, a modest application of fertiliser can be done in the early summer (that is, reasonable temperatures and soil moisture).

    During the summer months, you should refrain from fertilising trees and shrubs that are struggling due to drought. Do not apply any fertiliser at all if there is an insufficient supply of water, as the plants will be unable to take up the nutrients.

    Applying fertiliser to shrubs and trees in lawns at the right time of year and in the right amount will help the turfgrass thrive. Always check to see that there is an adequate supply of moisture, which might come from either natural rainfall or irrigation.

    Calculating Area & Fertiliser

    Fertilising the shrubs and trees that are growing in lawns should be done at the right time and in the right amount for the turfgrass (see Amount of Fertilizer to Apply section). It is necessary to determine the quantity of fertiliser that will be required for the growth of trees and plants in beds or natural regions.

    Calculating The Area Where Fertiliser Should Be Applied

    Apply the fertiliser to the area that is inhabited by the tree's roots, also known as the root zone area, in the case of trees. The region of the tree's root zone is roughly in the shape of a circle, with the tree itself located in the middle. The root zone region extends further than the drip line or the branches that are furthest from the trunk of the tree, and the roots themselves extend 1.5 times further than the distance from the trunk to the drip line or the branches that are furthest from the trunk. If the distance from the trunk of your tree to the drip line, which is referred to as the crown radius, is 8 feet, for instance, the "feeder" roots, which are responsible for mineral absorption, can extend an additional 4 feet beyond the drip line. Therefore, the root zone area can extend outwards up to a distance of 12 feet from the stem of the tree.

    Tree cultivars that have a narrow canopy, such as the Fastigiata English oak (Quercus robur 'Fastigiata') or the columnar Japanese pagoda tree (Sophora japonica 'Columnaris'), as well as trees with small canopies or trees that have been pruned into unusual shapes, have a root zone area that can be significantly larger than the drip line.

    In situations like this, you should base your calculation for the amount of fertiliser on the diameter of the trunk. First, take the diameter in inches at 4.5 feet above the soil level (dbh), and then multiply that value by either one or one and a half to get the number in feet. This is the measurement that will be utilised to determine the radius for the area that will be fertilised. For instance, depending on the factor that was used for the multiplication, the radius of the fertilisation area of a tree with a diameter of 12 inches would be anywhere from 12 to 18 feet.

    In order to calculate the amount of fertiliser required to supply 2 pounds of nitrogen per 1,000 square feet, follow these steps:

    Assuming the root zone occupies a shape that is generally circular, use the following formula to calculate the area of the root zone, where Pi is equal to 3.14.

    Pi x (radius)² = 3.14 x (root zone radius) x (root zone radius)

    In the preceding illustration, the area of the root zone would be calculated as follows: 3.14 times 12 times 12 = 452.16 square feet

    Use the following equation to determine the amount of fertiliser that is necessary for each 1,000 square feet of land:

    The number of pounds of nitrogen that is desired multiplied by the percentage of nitrogen that is contained in a bag equals the number of pounds of fertiliser that must be applied per one thousand square feet.

    In the event that you have access to a 16-4-8 fertiliser, the calculation for this particular illustration would look like this:

    2 pounds of nitrogen multiplied by 16 percent of 100, which equals 12.5 pounds of 16-4-8 needed per 1000 square feet

    Using the following calculation, determine the actual amount of fertiliser that to be applied:

    Root area in square feet 1000 square feet times the number of pounds of fertiliser needed per 1000 square feet equals the amount of fertiliser to spread over the root area. If you're looking for tree removal services, you’re in the right place! Check Tree Amigos!

    In our example, calculate the amount of fertiliser with the ratio 16-4-8 that needs to be applied in order to spread 2 pounds of actual nitrogen across 452 square feet:

    452 ft² 1000 ft² x 12.5 pounds fertiliser per 1000 ft² = 5.65 lbs fertiliser to spread over root area

    Spread 5.65 pounds of 16-4-8 equally across the root zone area. This is equivalent to around 11 to 12 cups, given that 1 pound of 16-4-8 is equal to 2 cups. When fertilising a tree, spread the fertiliser in a uniform layer over the area of the root zone using a rotary or drop-type spreader. This is necessary because the majority of the tree's roots are located in the top foot of soil. After application, water the soil to ensure that the nutrients reach the roots of the plant. If the root zone area of the tree is constrained by something like a sidewalk or driveway, the root zone area should be reduced proportionately.

    When fertilising individual shrubs, you should follow the recommendations that were given earlier for fertilising trees. When a number of shrubs are, however, planted in close proximity to one another in a bed or other natural area, it is much simpler to take a measurement of the entire area in order to ascertain how much fertiliser should be used. Take a measurement of the whole surface area of the bed, making sure to account for the roots of the plants whose limbs go beyond the boundaries of the bed. Use the following calculation to figure out how big the bed is:

    Root zone area equals length multiplied by width.

    Let's say the length of the bed is 30 feet, and the width is 10 feet. The area of the bed, also known as the root zone, is 300 square feet.

    Using the same calculations as in the section on trees, compute the amount of fertiliser that needs to be applied in order to get 2 pounds of nitrogen spread throughout 1,000 square feet. The first equation, assuming you have a fertiliser with the ratio 16-4-8, would look like this:

    2 Lbs N x 100 percent

    16 percent nitrogen corresponds to a need for 12.5 pounds of 16-4-8 per 1000 square feet

    Due to the fact that the root zone covers an area of 300 square feet, the actual quantity of 16-4-8 fertiliser that to be applied can be estimated as follows:

    3.75 pounds of fertiliser should be spread over the root zone if the area is 300 square feet and one thousand square feet.

    Spread 3.75 pounds (16-4-8) of the mixture, which is equivalent to roughly 7 or 8 cups, equally throughout the mulched bed. Fertilizer should be brushed off the branches, and then the plant should be watered to let the nutrients to reach the roots. If the root zone area of the shrub is going to be constrained by anything like a sidewalk or driveway, then the root zone area should be reduced proportionately.

    Apply 3.75 pounds (about 7 or 8 cups) of 16-4-8 evenly over the mulched bed. Sweep fertiliser off the branches and water afterwards to make the nutrients available to the roots. If the shrub’s root zone area is confined by a sidewalk or driveway, reduce the root zone area accordingly.

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