Roadside Revegetation

IMPLEMENTATION GUIDES
Determine Transplanting Versus Nursery Culture
Although cost may be the biggest deciding factor in whether wildlings are collected for
immediate transplant or growing in a nursery, other factors should enter into the decision in
the restoration plan.
Timing – Wildling plants should be transplanted into their new location as quickly as possible.
If plants are to be collected from sites outside the disturbed area, these can potentially be
removed and transplanted to the restoration site within the same time frame. However, if plant
removal is part of a salvage operation, where plants are located within the area of disturbance,
then plants could be transported to a nursery or similar growing situation. Plants should be
transplanted into pots and maintained until the appropriate outplanting season.
Species – Some plant species may be more successful than others for direct transplanting
from one site to another. Plants that spread underground or with stolons will perform well,
although dry, compacted sites will slow the rate of spread significantly (Therrell 2006). Species
that recover quickly from root damage, such as willows (Salix spp.) and cottonwoods (Populus
spp.), will also perform well when large plants are needed quickly. These types of plants may
lend themselves easily to transplanting within the same time frame as removal.
Plants with taproots, such as conifers and many shrubs, and plants with long, brittle horizontal
roots, such as heather or vine maple, are difficult to transplant. Special care must be taken
during removal to extract as much of the roots as possible. To ensure a higher success rate,
further culturing in an optimal environment following removal may provide a healthier, more
viable plant for outplanting.
Size and Availability – If wildling plants of the target species are plentiful and appropriately
sized on undisturbed sites, immediate transplant during the appropriate season is feasible.
However, if available wildlings are smaller than desired, an additional 1 or 2 years of nursery
culture may provide a better plant for colonization of the site.
Certain plants have the ability to root by layering, such as pinemat manzanita (Arctostaphylos
nevadensis). If entire plants are not plentiful, portions of individual plants can be removed
and cultured in a nursery situation for outplanting the following year.
Collection and Handling
Date of Collection and Timing of Transplanting – The season during which collection and
transplanting occur has been shown to dramatically affect the survival and growth of wildling
plants (Yetka and Galatowitsch 1999). Plants allocate carbohydrates and nutrients during various
phases of phenological development. Different levels of tolerance to transplanting stress
during the year are the result of physiological needs shifting among shoot and root growth,
flowering and seed production, and storage. In addition, seasonal variation in environmental
factors, such as soil moisture and temperature, can affect planting establishment (Steed and
DeWald 2003).
Timing of collection will depend on whether the wildlings are to be transplanted in the same
time frame or cultured in a nursery. If wildlings are to be transplanted into the restoration
site following collection, the chances for survival will increase for most species if operations
occur in winter to early spring. The seedlings are dormant during this period and can handle
the stresses associated with transplanting. There is also less chance of damaging new roots
that occur during the spring and fall. In addition, planting early extends the period for root
growth prior to soil-drying in summer.
Collection could occur in either fall or spring if wildlings are to be cultured in a nursery. However,
if plants are collected in the fall, care must be taken to avoid excessive root damage, since plants
will not be dormant. Due to the perishable nature of wildlings, the timing of collection must
be coordinated with the nursery to assure that the facilities, supplies, equipment, and labor
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