Roadside Revegetation

IMPLEMENTATION GUIDES
year, the seed collected from the field will average 800 pounds, a hundred-fold
increase. For most species grown in production beds for two years, the return
is at least 50 pounds of seed produced for every pound of wild seed collected
and sown. In some cases 100 pounds are collected per pound of wild seed sown.
This section will outline the steps required for developing and administering
seed increase contracts.
Develop Timeline
Seed production varies by species but typically it takes three years to obtain
seed. This involves one year to obtain seed from wild collections, and at least
two years for seed production (Figure 10-64). There are a series of steps or tasks
that are required to obtain seed that will be discussed in detail in this section:
Tasks
Determine seed needs
Obtain “starter” seed
Develop & award contract
Work with growers
Store seed
Develop sowing plan
Seed Production
Road Construction
Sow
◾◾
Determine seed needs
◾◾
Obtain starter seed
◾◾
Develop and award contract
◾◾
Administer contract
◾◾
Store seed
Early in the planning phase a rough approximation of the quantity of needed seed for each
species must be determined. Seed quantities will be refined as planning progresses, but
because of the amount of time that is takes for wild seed collection and seed production, it is
important to make an estimate early in the planning stages. Developing and awarding wild
seed collection contracts is the first task and this can take several months (see Section 10.2.4,
Nursery Seed Production). To avoid missing the seed collection window, these contracts must
be awarded by early spring, otherwise an additional year will be needed for wild seed collection.
Seed production contracts should be awarded by mid-July for fall sowing and late January for
spring sowing. It is important to prepare and award seed increase contracts well in advance of
sowing to allow the contractor enough time to prepare and sow their fields. Specific sowing
dates will differ for each seed producer because of differences in geographic location, climate,
or experience. Some growers may want to certify the seed, so this may require additional
preparation time as well. It is beneficial to contact the potential growers prior to award of
contracts to find out when sowing and first harvests are expected. Once wild seed has been
collected, cleaned, and tested, it is delivered to the seed producers.
Seed increase contracts should cover a span of at least two years, to account for the possibility
of a low first year harvest. Seed harvests take place during the summer and seed cleaning in
the fall of each year. Once seed has been cleaned, the grower submits a sample from each
seedlot to a seed laboratory for testing. Seed testing typically takes place in the fall and is
completed in several months. Seed is placed into seed storage until it is needed. For many
revegetation projects, the seed that is harvested in the summer is needed for immediate fall
sowing. This can be accomplished if those seedlots are put on a “fast track” for seed cleaning
and testing. The seed production contract should state those seedlots that need to be ready
for early fall sowing.
-3 -2
-1 0 1
Year
Figure 10-64 | Plan early
for seed production
Up to three years should be allowed
when obtaining nursery grown seed
because of the time it takes to obtain
wild collected seed and obtaining seed
from seed producers.
Determine Seed Needs
Determining total seed quantities for a revegetation project must be done as soon in the
planning process as is feasible since wild seed collection contracts and seed propagation
contracts are based on these figures. At this point, only a rough approximation of seed needs
is required.
Calculating the needed quantities of seed is performed for every species that will be used on a
revegetation project. Each species requires a set of data which must be estimated since specific
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