Roadside Revegetation

IMPLEMENTATION GUIDES
to the surface of the ground as possible, since maintaining an intact ball of soil around the
roots is important (Figure 10-59, Figure 10-60). Root morphology should also be considered in
this process. Roots growing in deep soils or arid soils will tend to grow down rather than out.
Roots growing in shallow soils will tend to spread, requiring a much larger area of disturbance
(Therrell 2006).
The shovel, as well as hands, can be used to lift the root ball gently out of the hole while
attempting to keep the root ball intact. Hand pruners can be used to cut away woody roots
that do not come free with the shovel. The root ball can then be transferred to a suitable
container (large bucket, pot, burlap, or plastic bag) for transport to the transplanting site
(Therrell 2006). If wildlings are to be transported to a nursery, plants should be placed in
plastic bags in coolers. Plastic bags should also contain moistened towels or similar material
if roots are not covered with soil.
A tree spade can be used if larger plants are to be excavated and transplanted (Figure 10-61).
The factors important for using a tree spade are (1) the terrain is accessible to the tree spade
equipment (slope gradients no greater than 20 percent), (2) soils are relatively free of cobble
size rock fragment, and (3) soils are moist. In this operation, planting holes are created first, then
plants are excavated, moved, and replanted. The size of the plant to be transplanted depends
on the soil volume that can be removed by the tree spade. Typically plants up to 6 feet tall can
be transplanted with success. Taller trees should be irrigated into the soil to improve survival.
Using a backhoe has also been successful in transplanting large willow clumps (Hoag 2003).
Wildlings should be transplanted into their new location as quickly as possible, with minimal
to no storage time. All vegetative material must be kept cool and moist during the process. If
wildlings are transported to a nursery, the plants should be kept in a cooler and transplanted
into pots within 1 to 2 days of collection.
Survival Potential
As with rooted cuttings (see Section 10.2.2.5, Determine Survival Potential), not all wildlings
will become established and thrive following transplanting. Survival is controlled by climate,
soils, planting methods, and maintenance practices on the project.
Climate – Water loss potential (see Section 5.4, Water Loss) is probably the main determining
factor for survival on many sites in the western United States. Sites with low moisture stress
during root initiation (spring through early summer), and sites that have the potential for
longer root initiation periods, will have higher survival.
Within a project area, aspect can also affect root initiation and survival. Transplanted wildlings
subjected to hot, dry conditions on southern aspects have a lower potential for survival than
those on cooler northern aspects.
Figure 10-60 | Salvage as much
of the root ball as possible
Plants can be excavated from the soil
using the drip line (dashed lines) as a
guide.
A
B
Figure 10-60 | Mechanical tree spade
Mechanical tree spades (A) can extract large
plants quickly. A planting hole must be excavated
prior to transplanting (B) and this can be
accomplished with a tree spade. Photo credit:
Chris Jensen, USFS.
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