Chapter 22 landscape maintenance.
This chapter begins with a brief background on landscape maintenance followed by the important aspects of pruning, including pruning goals, tree parts, pruning equipment, common questions about pruning, and general pointers in making pruning cuts. There are different methods for pruning different types of plants, including ornamental trees, fruit trees, grapes, flowering shrubs, evergreen shrubs, and deciduous trees. Proper care and maintenance of trees, shrubs, and flowering plants include proper watering; fertilization; and insect, disease, and weed control. The chapter concludes with a brief discussion of turfgrass care and maintenance.
After reading this chapter, you should be able to
* provide background information on landscape maintenance.
* discuss the important aspects of pruning.
* list and discuss methods used for pruning different types of plants.
* discuss the proper care and maintenance of trees, shrubs, and flowering plants.
* discuss turfgrass care and maintenance.
central leader method
modified central leader
open center tree form
An attractive landscape begins with a good design followed by proper installation and routine maintenance (Figure 22-1). The landscape designer must understand the level of maintenance that the customer wants. Some landscapes require high maintenance, whereas others require very little maintenance. Low-maintenance landscapes feature plants that do not require extensive watering, pruning, pest control, and mowing. No matter how good the landscape design is, all landscapes require regular maintenance. The amount of annual maintenance that needs to be done depends on the season, kind and age of plant, and the desired effect of the landscape design.
Pruning is a common landscape maintenance activity for both low-and high-maintenance landscapes. The best pruning results are achieved when specific pruning goals are planned prior to pruning. Examples of pruning goals are to trim plants to maintain their natural beauty or to obtain a desired effect, to eliminate dangerous branches, to enhance the overall heath of the plant, and to enhance flower and fruit production.
Proper pruning requires knowledge of the major external parts of the tree, including the crown, scaffold branches, trunk, roots, terminal, and water sprouts. In addition to the external parts of the plant, knowledge of the internal portions of the tree--the xylem, phloem, cambium, and pith--is important. Sharp pruning equipment provides the best results, but it should always be used safely. Commonly used pruning equipment includes shears, manual saws, power saws, pole saws, and pruners.
[FIGURE 22-1 OMITTED]
Pruning must be done cautiously with sharp tools by starting with parts that pose a threat to the plant, selecting wide scaffold branch angles, not pruning too close to the trunk, leaving a small portion of stem above the bud, and pruning to direct branches outward.
The three major types of pruning are thinning out, heading back, and renewal pruning. The main goals for training ornamental trees are to make the tree trunk strong, produce an attractive plant form, and establish a set height. The central leader method is commonly used for ornamental trees. For fruit trees, the main pruning goals are to develop strong scaffolds to support the weight of fruits, properly space branches to facilitate harvesting, and facilitate pruning, spraying, and other necessary orchard operations. The three major training and pruning systems used in orchards are the central leader, modified central leader, and the open center tree form method. Grapes are generally grown on the many types of trellises used in the industry; two commonly used types are single-wire and double-wire trellises, which can be spur pruned or cane pruned. Flowering shrubs must be pruned every year to make sure they flower year after year. After a flowering shrub has stopped flowering, rejuvenation pruning should be done to promote flowering again. Both small and medium evergreens growing in a foundation planting or as hedgerows require annual pruning. The two types of pruning methods used for evergreens are formal and informal (the informal is more commonly used today). Deciduous trees typically require very little pruning; however, they do require pruning to remove damaged, diseased, or insect-infested branches.
Another important factor in caring for trees, shrubs, and flowering plants is proper watering. Typically, watering is not needed when there is adequate rainfall; however, in times of drought, supplemental watering is necessary. The frequency of watering depends on the type of plant grown, stage of plant growth and development, soil properties, time of year, and cultural practices used. Fertilization is also necessary to maintain good plant growth, which enables plants to resist low-level pest populations. Trees and shrubs can be damaged severely by insects and diseases, so a standard IPM system should be in place. A successful landscape must also control weeds because weeds grow faster than landscape plants. Turfgrass must also be kept attractive and healthy by managing nutrients properly, watering, mowing, removing clippings, providing aeration, and controlling pests; this will be discussed in more detail in Chapters 23.
BACKGROUND OF LANDSCAPE MAINTENANCE
A good design and proper installation reduces the annual maintenance required by a landscape. In the initial planning stages, the landscape designer must understand the level of maintenance required by the customer. Some landscapes require a high level of maintenance, require many hours of work, and/or cost a lot of money. However, other landscapes look beautiful and can be maintained at a low cost. For a low-maintenance landscape, plants should be chosen that do not require extensive watering, pruning, pest control, or mowing. Irrigating the landscape is one of the major jobs in landscape maintenance; one way to reduce the workload for this task is to install an automatic watering system. If this type of system is too expensive, the lawn area can be reduced to decrease the need for irrigation. Reducing the lawn area also reduces the need for mowing. Ground covers are commonly used as a substitute when reducing the lawn size. Another way to reduce maintenance is to mulch regularly to reduce the need for weeding (Figure 22-2). In addition, many cultivars are resistant to a wide variety of diseases and insects that may be located in a particular location, thereby reducing maintenance. If raking leaves (Figure 22-3) is going to be a problem, evergreens should be substituted for deciduous trees. No matter how good the landscape design is, all landscapes require regular maintenance. The amount of annual maintenance required depends on the season, kind and age of the plant, and the desired effect of the landscape design. The following sections describe general maintenance activities required in all landscapes, including watering, controlling weeds, fertilizing, pruning, and controlling pests.
[FIGURE 22-2 OMITTED]
The study of trees, their growth, and culture is arboriculture. Pruning is a common landscape maintenance activity in both low- and high-maintenance landscapes according to a planned schedule or as needed. To obtain the best results it is important to have specific pruning goals in mind prior to pruning.
[FIGURE 22-3 OMITTED]
Examples of good pruning goals are as follows:
* Trim plants to maintain their natural beauty. Prune plants to regulate their size without affecting their natural beauty.
* Trim plants to obtain a desired effect. Pruning to achieve and maintain a desired shape depends on the type of plant and the desired effect (Figure 22-4).
* Eliminate dangerous branches. Pruning is also done for safety purposes by removing dangerous branches hanging over houses and walkways, which may pose a threat to structures or people walking under the branches. To keep trees healthy, immediately remove any broken or damaged tree branches after windstorms.
* Enhance overall plant health. To maintain healthy, actively growing plants, remove dead or diseased branches to protect the rest of the plant and adjacent plants from becoming infected. Branches can also be thinned to increase light into the center of the tree canopy and thus promote even fruit ripening.
* Enhance flower and fruit production. Most flowering and fruit-producing plants require annual pruning to flower and produce high-quality fruit on an annual basis.
[FIGURE 22-4 OMITTED]
To prune trees properly, the pruner must know the major external portions of the tree (Figure 22-5), which are crown or canopy, terminal or leader, scaffold branches, trunk, and suckers or water sprouts. Knowledge of the key internal portions of the tree is equally important (Figure 22-5).
Pruning equipment should always be sharp to get the best results. When pruning, eye and ear protection must be worn, especially when using power equipment. (Note that federal labor laws prohibit minors from operating power saws.) Pruning tools consist of a variety of saws and shears designed to cut different-size limbs at different heights and at different locations on the plant. Commonly used pruning tools are shears (hand, lopping, and hedge), manual saws (bow, tree surgery saw, two-edge saw, folding saw, ridge handle curved saw), power saws (electric power chain or gasoline powered), pole saws, and pruners.
Common Questions About Pruning
Is the use of tree topping a common practice today? In the past, tree topping--reducing the total tree height by one-third to one-half by removing upper scaffold branches--was common; however, it has since been found that this practice is not good for the tree. What is the best time of the year to prune? Late fall to early winter is the best time of the year to prune because few other farming operations are done at this time. Should tree paint be applied to cuts after pruning? Tree paint is no longer used commonly to protect wounds caused by pruning because it was not needed.
[FIGURE 22-5 OMITTED]
General Pointers for Making Pruning Cuts
A number of factors dictate the exact way a pruning method is implemented: type of plant, goal of pruning, the environment, and others. Regardless of the method, certain guidelines should be followed for successful pruning. Some general pointers are as follows:
* Define the pruning goals and the best time of the year to prune.
* Never take too much off; it is better to cut off too little and come back than to cut off too much.
* Use sharp tools to produce sharp cuts, which will heal faster than cuts that have been torn.
* Start pruning with parts that pose a threat to the plant, for example, any dead or dying materials.
* Select branches with a wide branch angle (45[degrees]) because branches with a narrow angle (20[degrees]) will split under windy conditions or from the weight of fruit.
* Do not prune too close to the trunk because doing so will make a large wound that will not heal properly; leave a small portion of the stem to create a smaller wound that will heal properly. Do not leave too much of a stub from the branch being pruned because disease can enter through the stub (Figure 22-6).
* Leave a small portion of the stem above the bud; too much stem left can result in disease entry and too little can result in desiccation of the bud.
* Prune branches that are growing inward toward the center of the tree, but leave outward growing branches. When pruning is done properly, bud growth can be directed by selecting buds.
[FIGURE 22-6 OMITTED]
PRUNING DIFFERENT TYPES OF PLANTS
The three basic strategies for pruning are thinning out, heading back, and renewal pruning. Thinning out is the removal of excessive vegetative growth to open the plant canopy and reduce the number of fruiting branches with the goal of promoting larger and overall better-quality fruits. By thinning out the plant, more light is able to penetrate to promote better fruit set, increased productivity, and overall quality. Heading back is the removal of the tips of terminal branches to promote secondary branching. This type of pruning makes the plant look fuller; its shorter size may even promote a new shape. Renewal pruning is used to rejuvenate old plants by removing old unproductive branches, thereby promoting vigorous growth. This is commonly used in flowering shrubs that have stopped flowering and fruit trees that have been neglected.
The main goals of training ornamental trees are to make the tree trunk strong, produce an attractive plant form, and establish a set height. To develop a strong trunk, the central leader method is commonly used. The central leader method identifies and trains one strong upward-growing branch to grow as the central axis of the tree; the central leader is the main upright shoot of the tree. Ornamental trees take time to establish their form; however, they can be trained into several forms: feathered, standard, branched-head, weeping standard, and multistem tree form (Figures 22-7 and 22-8). The head height is the height of the scaffold branches (the main branches growing from the trunk of the tree) above ground at the adult stage (Figure 22-9).
[FIGURE 22-7 OMITTED]
[FIGURE 22-8 OMITTED]
[FIGURE 22-9 OMITTED]
The pruning goals for fruit trees are to develop strong scaffolds to support the weight of fruits and properly space branches to facilitate harvesting, pruning, spraying, and other necessary orchard operations. Pruning can also control the time to first fruiting, promote fruiting on a yearly basis, produce attractive shapes especially when used in the landscape, and confine the tree to space available. One of the main reasons for training and pruning fruit trees is to increase productivity and to make harvesting and other operations in the orchard easier. The three major training and pruning systems used in orchards are the central leader, modified central leader, and the open center.
[FIGURE 22-10 OMITTED]
Central Leader Tree Form
The central leader method is commonly used for dwarf and semidwarf fruit trees, such as apples and sweet cherries, and produces narrow- and conical-shaped trees with several tiers of scaffold branches (Figure 22-10). The uppermost bud becomes the upright central leader of the tree. Then three or four lateral branches with wide-angle crotches that are spaced equidistant around the tree are selected for the frame of the tree. To prevent the central leader from bending and stopping terminal growth, fruiting on the upper third of the terminal should be discouraged. Water sprouts should be removed as they develop.
Modified Central Leader Tree Form
The modified central leader system is the same as the central leader tree form system in the early stages to permit the formation of strong scaffold branches. After all the scaffold branches are established, the central leader is removed, creating an open center (Figure 22-11).
[FIGURE 22-11 OMITTED]
Open Center Tree Form
The open center tree form is commonly used for peaches, nectarines, plums, pears, and others. This method allows easy access to the tree for fruit thinning and allows for good sunlight penetration to help fruit ripen (Figure 22-12). The starting point for training a plant for the open center system is to head the plant. Heading promotes new growth required for the training period. During the first dormant season, three to four branches are selected to be scaffold branches, and the remaining branches are removed. The branches should be spaced equal distances apart, leaving enough room for growth.
[FIGURE 22-12 OMITTED]
Grapes are usually grown on the many types of trellises used in the grape industry. Two commonly used trellises are single-wire or double-wire trellis types, which can be spur pruned or cane pruned. Spur-pruned vines have a permanent trunk and arms. During the winter months, the previous season's growth should be cut back to two to four buds, thereby creating a short shoot resembling a fruit tree spur. In the spring, the buds will break dormancy, grow slightly, and then produce flowers and fruits on a lateral bud from the current season's growth (Figure 22-13). Cane-pruned vines differ from spur-pruned vines because they only have a permanent trunk. At the end of each season, the old canes are removed by pruning and three or four spurs are left at the top of the trunk to provide a place for new cane to form the next season. Annually, new canes are placed on the trellis as arms to support the fruit (Figure 22-14).
[FIGURE 22-13 OMITTED]
[FIGURE 22-14 OMITTED]
Proper pruning must be done every year to make sure that flowering shrubs flower year after year. Shrubs develop next year' s flower buds immediately after flowering each year, so pruning must be done carefully to avoid removing the flowering buds. Rejuvenation pruning is used on shrubs that have not been pruned properly and have stopped flowering.
Small and medium evergreens growing in a foundation planting or as hedgerows require yearly pruning. Landscape designers typically recommend yew (Figure 22-15), juniper, aborvitae, or boxwood evergreen varieties. There are two types of pruning methods for evergreens:
* Formal. Formal hedges are created by planting and pruning to form a specific geometric shape. A topiary is a plant that has been trained and pruned into formal geometric or abstract shapes. Yews and boxwood are commonly used for topiaries because they are easy to train, evergreen, and long-lived. Topiaries need to be maintained to keep their form and beauty (Figure 22-16). The degree of pruning depends on the plant type, plant vigor, form design, and demand by the owner.
* Informal. Today the formal look is not used widely; rather the informal look is used commonly because it emphasizes a natural look, which is more appealing. Informal hedges are allowed to grow freely in their natural shape (Figure 22-17) and are pruned only to restrict size and to remove damaged branches. Because evergreens are used commonly as hedges in the landscape, it is important to know that they have a dead zone, which is the area 6 to 12 inches below the green needles on the branch. Most evergreens cannot develop new leaf buds after pruning into the dead zone, so cuts should not be made in this region.
[FIGURE 22-15 OMITTED]
[FIGURE 22-16 OMITTED]
[FIGURE 22-17 OMITTED]
Shade trees growing in the home landscape typically require little pruning. Most pruning of deciduous trees relates to removing storm- or disease/insect-damaged branches for safety reasons.
CARE OF TREES, SHRUBS, AND FLOWERING PLANTS
Proper care of trees, shrubs, and flowering plants includes watering, fertilizing, and controlling insects, diseases, and weeds.
Watering is typically not important when there is adequate rainfall; however, in times of drought, supplemental watering is necessary. Watering in a typical landscape is frequently performed improperly. Many gardeners feel that if the soil surface is wet, the plants have received adequate water; however, this is incorrect. The proper way to water is to wet the root systems of plants, so the grower needs to know where the roots of a given plant are located. Roots grow toward water, so if only the ground surface is watered, then the roots will stay near the surface making it necessary to water more frequently. However, if the plants are watered deeply, a deeper penetrating root system will be promoted. The frequency of watering depends on a variety of factors as described in the following paragraph.
The type of plant being grown is very important to consider when watering plants. For example, some plants are drought tolerant or have deep root systems that enable them to withstand fairly long periods of time without water. However, lawns and a variety of bedding plants need to be watered frequently in the absence of natural rainfall.
Another important consideration when watering plants is the stage of plant growth and development. When plants are being established in the landscape, more frequent watering is necessary; whereas after they are established, less frequent watering is necessary. Watering is also critical during flowering and fruiting because if water stress persists during this time, it will cause flower and fruit drop.
Soil properties have a profound effect on when plants need to be watered. For example, in sandy, well-drained soils, it is necessary to water more frequently than in soils with a high organic matter content.
The time of the year has a dramatic effect on when supplemental water needs to be added. During the early spring there is frequently more rainfall then during the summer months therefore more supplemental water will be needed during the summer months for plants that are sensitive to reduced water conditions.
Cultural practices also affect when plants need to be watered. For example, the use of mulch or plastic reduces evaporation, thereby improving water retention by the soil.
Several methods are commonly used for watering plants in the landscape hand watering, sprinklers, and drip irrigation. Hand watering is typically done on a small scale. Sprinklers are popular for watering lawns and flowerbeds because they can be used to water a larger area, however, water is wasted because the area cannot be confined and evaporation occurs. Drip irrigation in flowerbeds provides water to a specific location and makes efficient use of water because you are targeting specific plants and less water is lost due to evaporation. The downside of drip irrigation is that drip lines may become clogged (Figure 22-18).
[FIGURE 22-18 OMITTED]
Fertilization is necessary to maintain good plant growth, which enables plants to resist many diseases and pests. Starter solutions are used to get plants established. After they are established, fertilizer is used to sustain active vegetative growth and flowering. Although fertilization can be used to increase flower production, it will also increase the shrub's total growth, which will necessitate additional pruning. Late summer or early fall fertilizer application should be avoided because it may delay the plants' preparation for the winter dormancy period and lead to plant damage. Fertilizer application methods include the following:
* Top dressing. Sprinkling granular fertilizer around the base of the plant.
* Liquid. Watering with fertilizer.
* Fertilizer spikes. Inserting solid spikes directly into the soil around the plant.
Insects and Diseases
Trees and shrubs can be damaged severely by insects and diseases. Insects with either chewing (caterpillars and bag worms) or sucking (aphids, scale insects, mites) mouthparts are problematic. Diseases caused by bacteria, fungi, and viruses are also problems in trees and shrubs. In most cases, pests do not cause significant problems in the landscape but they do cause yellowing of foliage or blemishes, which reduce the aesthetic value of ornamentals. A standard IPM system is important for controlling insects and diseases. When cultural, biological, mechanical, and genetic control procedures no longer control the pest, chemicals may be used. Table 22-1 lists problems caused by pests, control measures, and plants affected.
Weeds grow faster than landscape plants and create numerous problems. Weeds must be controlled to prevent the landscape from becoming overrun. The use of herbicides should be a last resort because people and their pets play on the lawn and handle plants. An IPM program around homes should start with cultural methods for weed control. Weeds should not be allowed to grow to a point where they set seed. Weeds can be removed physically by hand (Figure 22-19) or using a hoe, which also improves the soil structure. The use of ground covers, mulch, and plastics is the most effective method of weed control in the landscape. When herbicides have to be used, the grower should read the safety sheet and label the location properly so people know and understand that chemicals have been used.
[FIGURE 22-19 OMITTED]
TURFGRASS CARE AND MAINTENANCE
Turfgrass maintenance involves keeping a stand of turfgrass in an attractive and healthy condition by managing nutrients properly, watering, mowing, removing clippings, providing aeration, and controlling pests. For more details on turfgrass care and maintenance, refer to Chapter 23.
You now have a basic understanding of what is necessary to maintain a landscape properly. The important aspects of pruning include pruning goals, tree parts, pruning equipment, common questions about pruning, and general pruning pointers. Different methods are used for pruning different types of plants, including ornamental trees, fruit trees, grapes, flowering shrubs, evergreen shrubs, and deciduous trees. The proper care and maintenance of trees, shrubs, and flowering plants includes watering, fertilization, and insect, disease, and weed control.
Review Questions for Chapter 22
1. What are five important pruning goals?
2. List the five important external portions of the tree and the four key internal portions of the tree.
3. What should be done to pruning equipment prior to use to obtain the best results and what are five commonly used pruning tools?
4. What are eight general pointers that should be followed when making pruning cuts?
5. What is the best time of the year to prune and why?
6. Should tree paint be used to protect wounds after pruning?
7. What is tree topping, and is it commonly used today?
8. What are two commonly used trellises and two pruning methods used for grapes?
9. When do flowering plants initiate their flower buds?
10. What are two pruning methods commonly used for evergreens, and which one of the two is more commonly used today?
Define the following terms:
central leader method
modified central leader system
open center tree form
True or False
1. A good design and proper installation does not mean there will be a reduction in the amount of annual maintenance.
2. It is not always important to have specific goals in mind prior to pruning to achieve the best results.
3. An important pruning goal is to maintain the plants' natural beauty.
4. An important pruning goal is to decrease flower and fruit production.
5. Tree paint is commonly used to protect wounds after pruning.
6. When pruning, it is important to select branches with narrow branch angles to achieve a more compact plant.
7. When pruning, it is very important to prune as close to the trunk as possible.
8. The best time of year to prune is during the late fall to early winter because few other farming operations are done at this time.
9. Tree topping, which reduces the total height of the tree one-third to one-half by removing upper scaffold branches, is a common practice today.
10. Grapes are usually grown on trellises.
11. Flowering shrubs develop next year's buds during the early spring.
12. Evergreens have a dead zone 6 to 12 inches below the green needles.
13. Shade trees growing in the home landscape require little pruning.
14. Fertilization can be used to increase flower production in trees, shrubs, and flowering plants.
15. In times of drought, trees and shrubs do not require watering.
1. Arboriculture is the term used to describe
A. early civilizations or cultures that used plants in the landscape.
B. the study of the culture of plants for their usefulness in medicine.
C. the study of trees, their growth, and culture.
D. None of the above
Fill in the Blank
1. -- is the study of trees, their growth, and culture.
Place the proper term in the space provided for the internal portions of the stem. Terms: phloem xylem cambium pith
Now that we have completed our discussion on landscape maintenance, you will have the opportunity to explore this area in more detail. Go to a location near you and look for homes or other buildings being landscaped and take pictures of what you see at these sites. Write a description of what type of maintenance is needed and what is being done properly, plus anything else you can think of regarding maintenance of the landscape. If there is no landscape maintenance going on in your particular area or you want to supplement your findings, search the Internet. Be sure to include the Web site address for all the sites discussed.
TABLE 22-1 PROBLEMS CAUSED BY PESTS, CONTROL MEASURES USED, AND PLANTS AFFECTED IN THE LANDSCAPE Pest Plants Attacked Control Aphid Cole crops Diazinon or Malathion Fruit or ear worm Corn or tomato Sevin or Diazinon Damping-off Tomato, pepper Captan and Thiram Downy mildew Cole crops Zineb or Maneb Ants Lawns Diazinon or Sevin Armyworm Trees and shrubs Diazinon or Carbaryl Japanese beetle Trees and shrubs Diazinon Caterpillar Landscape plants Diazinon or Sevin Borer Fruit trees and ornamentals Lindane or Dimethoate Mite Annuals, perennials, Malathion or Kelthane trees, and shrubs
|Printer friendly Cite/link Email Feedback|
|Author:||Arteca, Richard N.|
|Publication:||Introduction to Horticultural Science|
|Date:||Jan 1, 2006|
|Previous Article:||Chapter 21 installing landscapes.|
|Next Article:||Chapter 23 warm- and cool season turfgrass selection, establishment, care, and maintenance.|