Chapter 3—The Art and Science of Restoration

• 3.11 Transplanting, Protecting, and Establishing Native Plantings
  • 3.11.1 Timing of Transplanting
  • 3.11.2 Transporting Nursery-Grown Plants to the Project Location
    • 3.11.2a Jelly Rolls for Protecting Bareroot Stock
    • 3.11.2b Moving Plants in Containers
    • 3.11.2c Moving Container-Grown Plants Without the Container
    • 3.11.2d Protecting Fragile Foliage
    • 3.11.2e Moving Plants With Helicopters or Other Vehicles
    • 3.11.2f Handling Plants After They Arrive at the Project Location
  • 3.11.3 Transplanting Techniques
  • 3.11.4 Salvaged Materials

3.11 Transplanting, Protecting, and Establishing Native Plantings

Proper transport and transplanting procedures are critical to the survival of transplants. In addition, all plants must be given adequate water, mulch, shade, protection from animals that might eat them, and so forth.

3.11.1 Timing of Transplanting

The timing of transplanting will vary depending on the species, the environment, and the ability to provide initial care, such as irrigation, for transplants. In general, transplants need time to become established before being subjected to potentially lethal environmental extremes. In most environments, transplanting takes place during the spring or fall while the plants are dormant, just emerging from dormancy, or preparing for dormancy. Transplanting in winter is possible in environments where the ground is not snow covered or frozen. Although transplanting during the summer should not be ruled out completely, doing so risks subjecting plants to drying winds, too much heat, and inadequate moisture. The roots of some species grow only when they have adequate soil moisture.

For arid lands, most practitioners advocate fall or early winter plantings (figure 3-124). Desert plants have warm- or cool-season growth patterns. Cool-season species are best planted in the fall, while warm-season species, such as blackbrush (Coleogyne ramosissima), may transplant better with a spring planting. Planting in hot deserts is often done during winter (Belnap and Furman 1997). According to some practitioners, timing is not as critical as one might expect. Midsummer plantings of mesquite (Prosopsis glandulosa) have had high survival rates, but other species such as palo verde (Cercidium floridum), were more sensitive to drying wind and high heat (Bainbridge and others 1992).

Figure 3-124—For arid sites, fall or early winter plantings
are the most likely to be successful.

In subalpine environments, transplanting generally occurs in September and into October (figure 3-125) when soils are moist (minimizing the need for additional watering after planting) and plants are slowing their metabolism before entering a dormant phase. It is possible to transplant just after the snow has receded in the early summer, or by late August, but the survival rate of plantings will be lower. Irrigation is likely to be needed throughout the remainder of the growing season.

Figure 3-125—In subalpine areas, planting is done in
September and October just before the winter snowfall.

And finally, plants should be transplanted before they seed. Otherwise, seed will be churned in too deeply or fragile seedlings will be damaged.

3.11.2 Transporting Nursery-Grown Plants to the Project Location

Nursery-grown plants may have their foliage or roots desiccated, their foliage crushed, or their stems broken when they are transported to the restoration site. The method of transport also can have an impact on the physical landscape or soil. For example, using a helicopter to transport plants quickly and with no disturbance to soil and vegetation may be a good option, but this practice conflicts with wilderness values. Even though mules or llamas (figure 3-126) may cause noticeable soil disturbance when they are used to transport plants to a fragile location, this disturbance may be less than the disturbance caused by the feet of the many workers needed to accomplish the same task.

Figure 3-126—Llamas or mules work well for transporting
plant materials to most work sites. It's best to get the packstock
in and out quickly so the animals don't damage your project site.

Plants should not be brought into the project area before transplanting is scheduled. This is especially important in arid environments, where shade and water are scarce. In a more temperate environment, plants can be held over for short periods by storing them in the shade and watering them as needed.

A number of methods have been developed for packing and transporting plants. It is critical to protect plants from exposure to air, heat, cold, or sunlight. Containerized plants should be watered before being transported. If weight is an issue, plants may be transported for a brief time with partially moist soil. Weed seedlings or moss growing on the potting medium should be removed before transport. If heat is a concern, some ventilation needs to be provided, while the plants also need to be protected from wind. Light-colored canvas tarps work better than plastic tarps because the canvas allows for some ventilation, reducing the risk of overheating.

3.11.2a Jelly Rolls for Protecting Bareroot Stock

When bareroot seedlings are lifted out of their growing medium, they can be dipped in a slurry of water and vermiculite and placed on damp fabric. The fabric is rolled as more plants are added. The rolls are placed in plastic bags and kept cool (39 degrees Fahrenheit, 3.9 degrees Celsius) in a controlled environment or by placing them on ice. Dry ice should not be used, because it is too cold and is toxic to plants. In addition to keeping roots moist, jelly rolls reduce the weight of the materials needed to transport seedlings and the space required to do so. For example, 98 plants in a sand-filled rack of supercells weigh about 50 pounds (22.7 kilograms), compared to 30 pounds (13.6 kilograms) for an ice chest holding 300 plants in jelly rolls packed on ice (Bainbridge and others 1992). Plants can be rolled in wet burlap, but reusable toweling works best for jelly rolls. For additional information on jelly rolls and reusable toweling, refer to Reusable Toweling for Wrapping Tree Seedlings, available at http://www.fs.fed.us/t-d/php/library_card.php?p_num=0524 2323.

3.11.2b Moving Plants In Containers

Plants that are in containers need to be placed in a relatively rigid device with enough packing material between pots or flats to prevent them from being damaged by jostling during transport. If packstock are used to carry the plants, plan for "rodeos"—try to pack the plants so they will not be damaged if loads are thrown topsy-turvy. Containers help protect the roots from desiccation during transport and make it easier to hold and move plants at the project location. Disadvantages include the larger volume of containers that will need to be carried in and out.

Tree-planting boxes are large, sturdy waxed-cardboard boxes in which the Forest Service receives shipments of tree seedlings. These boxes, usually discarded after planting, are the perfect size for stacking rectangular flats of plants in small containers (figure 3-127). Stacking works well for plants that can withstand moderate crushing, such as graminoids, or plants with rhizomes or stolons. Small spacers can be added across the corners of the flats to reduce crushing. The boxes fit one to a side in canvas panniers or manties for transport on packstock and can be flattened for packing out.

Figure 3-127—Discarded Forest Service tree-planting boxes
are the perfect size for loading flats of plants. Spacers can
be used between flats to prevent crushing delicate species.
Packing material can be added to take up excess room. These
boxes fit in panniers, so they can be used with packstock.

For plants that cannot withstand the abuse of being stacked, find shallow boxes that will hold one layer of containers. Many office supply stores or shipping businesses sell a variety of boxes and are likely to have some that meet your needs. Racks can be devised for transporting plants in cells.

3.11.2c Moving Container-Grown Plants Without the Container

In general, it is best to move the plant in its container because the container will protect fragile roots. Some species, such as grasses and sedges, have well-developed root systems that can withstand the abuse of being removed from pots for transport. The soil around the plants should be moist to protect roots from desiccation.

Package plants by removing them from their pot and placing them in layers in large plastic bags lining larger containers, such as 5-gallon (19-liter) buckets (figure 3-128), boxes, or stock panniers. A sheet of newspaper between each layer of plants may help keep the seedlings separated.

Figure 3-128—Sturdy plants, such as sedges, can be removed
from their pots and transported directly in buckets or
boxes to save space.

3.11.2d Protecting Fragile Foliage

Plants with fragile stems, such as lupine, are difficult to transport. The fragility may influence the type of transport; packstock may not be appropriate. Cylinders can be made around the plants. For instance, each plant could be rolled securely in newspaper and packed so they remain upright. Use enough packing material to keep the plants from shifting.

3.11.2e Moving Plants With Helicopters or Other Vehicles

Plants can be packaged for planting using any of the methods described above. During transport, the plants need protection from wind. A canvas tarp can be used to cover loads that would be exposed otherwise.

3.11.2f Handling Plants After They Arrive at the Project Location

Upon arrival, plants should be watered and stored in the shade. If no shade if available, a shelter can be constructed from a canvas tarp or shade cloth. Most subalpine species can be placed in shallow water for short-term storage, such as in a pond, a shallow pool or a creek, or even in toddler wading pools set up in the shade. Branches or leaves that were damaged during transport should be cut back.

3.11.3 Transplanting Techniques

The same method is used for planting wildlings as for nursery stock. Good transplanting technique will improve the survival rates significantly. Common mistakes include planting seedlings too shallow, too deep, or too loosely; orienting wildlings incorrectly; damaging roots by exposing them to air; or failing to place root stems properly. With transplanting, the quality of the work needs to be monitored and supervised carefully. Quality—not production rate— should be given first priority.

Ideally, the spacing of plants is specified. For a natural appearance, plantings should be grouped in irregular patterns. The planters should observe the natural distribution and spacing of each species and try to emulate that pattern. When plants are not available at the correct ratios for such a pattern, planters must use their best judgment to mimic the native stand. If seedlings are planted too densely, they may need to be thinned or moved as they mature. It may be wise to plant a few more seedlings than desired to compensate for mortality.

Ideally, seedlings should be planted on a cool, cloudy day or while the restoration site is in shade. Experience will determine how important these recommendations are for your project. Water the seedlings before planting them. Dig the planting holes before exposing the seedlings' roots to the air. Planting holes should not be allowed to stand empty for too long, because the exposed soil will dry out rapidly. When possible, planters should take advantage of microsites, such as rocks, logs, or depressions, to give the seedlings a bit more protection from sun or wind (figure 3-129).

Figure 3-129—Planting seedlings against a log or rock helps
protect them and provides them additional water.
This photo was digitally altered.

A variety of tools, including shovels, hoedads, and dibbles, can be used to dig planting holes. For small containerized stock, small hand-held pick hoes (figure 3-130) are the most efficient planting tools. In areas where soils are deeply compacted, a rock bar or soil auger may be needed to dig planting holes. Power augers may be the minimum tool for digging holes on especially difficult soils, such as caliche. In clayey soils, augers may leave a smooth glaze on the soil that is difficult for roots to penetrate; this glaze can be prevented by using specialized auger attachments.

Figure 3-130—Trowels are not the tool of choice for planting. A hand-held
pick hoe (shown) or plow share works well for planting smaller plants.
A shovel is needed when planting larger plants.

The planting hole is dug about one-third larger than the root system of the transplant. The soil should be loose on the sides and bottom of the hole. Water the planting hole with enough water to saturate the soil. Trim damaged roots off transplants, and gently tease roots apart if containerized plants are rootbound.

When placing the plant in the hole, maintain the natural alignment of the roots. Be sure that the roots are not doubled back. Taprooted plants, such as tree seedlings, will die if their roots are doubled back because the root system cannot correct its orientation to reach water in the deeper soil layers. If transplants have fibrous root systems, it sometimes helps to build a mound in the bottom of the hole and spread the roots out around this mound.

The crown of the plant should be at or slightly below ground level; some species will die if the crown of the plant is buried. A slight depression will catch water and afford a measure of protection from the elements. Another way of catching water is to build up a rim of soil around the transplant. The hole is backfilled, tamping the soil firmly without crushing plant material, and watered layer by layer (figure 3-131). Make sure to spread roots in the hole. Finally, planters should use the weight of their forearms or feet to snug soil down, removing air pockets from the soil around the transplant's roots.

Figure 3-131—Once a transplant is placed in a hole, soil is packed
firmly around it to eliminate large air spaces. Gently stepping
around the transplant helps snug it in. A shallow depression
around the transplant will help retain water.

Tamping also helps prevent frost heave. Shallow plugs of sod may need to be anchored with pegs so they maintain firm soil contact. At Denali National Park, restorationists use U-shaped pins made from rebar to anchor shallow-rooted trees. The pins help keep the trees from toppling over (Densmore and Vander Meer 1998).

The quality of the transplanting job can be monitored by tugging gently at each seedling. If a plant pulls loose, it needs to be replanted more securely. The planters should monitor their own work, and a supervisor should conduct spot checks for quality control.

When planting seedlings among living roots, plant between the roots as much as possible. In some cases, such as with huckleberry, roots resprout once growing conditions are favorable. Ruth Scott has found the opposite to be true at Olympic National Park; sites where root systems were minimally disturbed during planting were slow to recover. Better overall results were obtained by thoroughly scarifying the soil before replanting (Scott 2002).

Plants have tiny root hairs that are destroyed almost immediately when they are exposed to air. These root hairs represent a large percentage of the total surface area of the root system. It is crucial to avoid exposing the root hairs to the air. At Joshua Tree National Park in the Southwest, the tall pots used to grow seedlings with long roots have a screen on the bottom. When the seedling is planted, the screen is removed and the entire plant—including the pot—is lowered into the planting hole. While a stout dowel is used to push the plant down, the pot is removed slowly as soil and water are added into the hole around the roots. Holes drilled near the rim of the pots allow hay hooks to be used to lift the pot away from the plant. This technique protects the delicate root systems (figures 3-132a and 132b).

Figures 3-132a and 132b—Roots can be kept moist when seedlings
are grown and planted in PVC pots with removable screen bottoms.
Once the pot and seedling have been planted (top), the pot can be
removed (bottom), as shown here at Joshua Tree National Park, CA.

Transplants should be watered as soon as they have been planted. Wildlings should be pruned back by one-half to one-third of their original size if the plant's morphology allows pruning. If transplant shock is anticipated, an antidesiccant spray can be applied to the foliage. Mount Rainier and Denali National Parks water their transplants with Vitamin B1 to prevent transplant shock (Densmore and Vander Meer 1998; Rochefort 1990). Vitamin B1 is available from nursery suppliers or garden supply stores.

If soils at the restoration site are altered significantly, the site could be inoculated with mycorrhizal fungi or nodules containing nitrogen-fixing bacteria by spreading a thin layer of inoculum in the planting hole. The methods for doing so are described in section 3.2.5b, Inoculating Plants With Mycorrhizal Fungi.

Consider situating some plantings against rocks or logs. The rock provides additional protection and additional water, especially if a long, sloped surface directs water to the plant.

Some irrigation devices, such as deep pipes or clay pots, are installed as part of the planting process. Mulch, shade cards, signs, and devices to reduce wildlife damage generally are installed immediately after planting. These techniques are described in section 3.12, Plant Protection and Establishment.

3.11.4 Salvaged Materials

Ideally, transplants should be planted as quickly as possible. Plants can be held for a short period of time in the shade or shallow water (figures 3-133a and 133b).

Figures 3-133a and 133b—For a short time, salvaged plant materials
can be stored in shallow water (top) or in the shade (bottom).

Sometimes, salvaged materials cannot be planted quickly because they need to be removed long before the area is ready. The plants may have to be held for an extended period.

In general, holding beds, similar to a garden, are used for the salvaged plants. Plants are provided with irrigation and shade, as needed. You may need to prune back the crowns of the plants to improve the root-to-shoot ratio. If you plan to salvage plants, check with local restorationists to learn the methods that work best for your species. Plants may require additional protection, such as a thick layer of mulch or sawdust, if they are held over winter.