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Alternative Container Design for Large Acreage
Revegetation
Background
Revegetation of arid lands disturbed by fire, or by cropping,
mining, and other activities, represent a continuous and substantial
expenditure by the responsible entities. Federal legislation such as
the Surface Mining Control and Reclamation Act, the Conservation
Reserve Program, and Comprehensive Environmental Response,
Compensation, and Liability Act require the planting of native
seed/seedlings and the expenditure of millions of dollars annually
on sites that are highly disturbed or contaminated from activities
such as mining, agriculture, industrial activities, and forest
fires.
With regards to arid land shrubs, mechanical seeding
and transplanting of nursery-grown plant materials compete directly
for revegetation dollars but are not equal in their efficacy.
Mechanical seeding is an inexpensive, but highly ineffective means
of restoring arid land shrubs to disturbed sites. Mechanical seeding
of arid land shrubs has proven largely ineffective for several
reasons, including low seed efficiency, low seed availability,
inability to effectively produce large quantities of seed from
appropriate genotypes, and the increased hazard of noxious weeds
introduction either naturally or from wildland seed collections.
Transplanting of nursery propagated arid land shrubs, in contrast,
negates many of these concerns and is highly successful but can be
prohibitively expensive. If the cost of effective arid land planting
stock can be substantially reduced, however, transplanting will
likely become the revegetation method of choice on millions of acres
of lands damaged by fire, mining, agricultural activities, and other
disturbances.
The primary cause for this failure to produce
cost-effective arid land planting stock is the lack of a container
system designed specifically for arid land plant species. Current
container systems have been designed for horticultural and forestry
applications. In general, plant species grown for these applications
are ecologically, morphologically, and physiologically different
than arid land plant species grown for restoration projects. When
these factors are taken into account, it is possible to design a
short duration, high-density plant container system that will
minimize nursery inputs without sacrificing infield survival. The
benefit to be realized by clients is an inexpensive, highly
adaptable source of arid lands planting stock that provides
successful field establishment. A substantial potential market
exists for a container plant system that produces low cost seedlings
for arid lands restoration projects.
Bitterroot Restoration, Inc. in collaboration with
U.S. Department of Agriculture, Agricultural Research Services
received a Phase I U.S. Department of Agriculture Small Business
Initiative Research grant to develop a low cost alternative
container design for use in large-scale transplanting projects in
arid lands. This project is being conducted at a number of locations
across the western United States including the Idaho National
Environmental Research Park at the INEEL.
Objectives
The technical objective addressed with fieldwork at the INEEL was to
determine the percentage survival of sagebrush established in Booth
Tubes versus other currently used forestry containers.
Accomplishments through 2002
Nine field study sites were established throughout the Western
United States. The various sites represented different potential
client types (i.e., mine industry, federal agency), different
initial site conditions, and a broad geographic area. All sites
experienced the continuing Western drought.
Each study site consisted of a completely randomized
block of 200 replicates per treatment. Treatments were (1) 8 x 1
Booth Tube, (2) 164 cm3 (10 in3) Ray Leach Cone-tainer, (3) 65 cm3
(4 in3) Ray Leach Cone-tainer, (4) Ecopot-PS-315, (5)
PaperPot-FS-315, and (6) Zipset Plant Band 1.25 x 6 in. Plant
materials in all container types were produced under greenhouse
conditions. Shipping and packing times for each container type were
recorded. Field planting with hand planting tools occurred from
mid-March through early May. Field planting times for each container
type were recorded at each site. Field data (survival and height)
collection occurred in August and September with one exception. The
La Plata, New Mexico, site was dropped from the study because of
complete mortality resulting from severe drought as reported by the
project cooperator.
Analysis for the study consisted of calculating means
for survival data at individual study sites. Planting rate and
shipping rate data were compiled, averaged, and times normalized on
a per thousand plant basis. Based upon this, estimated shipping and
planting labor cost rates were applied to estimate cost efficiencies
associated with each container type.
Results
Plant survival varied widely between sites and was highly dependent
upon site moisture conditions. In general, the Bingham Canyon, Utah
site was a dramatic success, while all other sites were judged as
failures. Bingham Canyon received the highest precipitation amount
(60 cm [19.7 in]) while La Plata Mine received the lowest
precipitation (6.4 cm [2.5 in]). The Bingham Canyon Mine site
experienced the most favorable moisture conditions resulting in
excellent survival of Booth Tube containers (76 percent). At this
site, the Booth Tube was equal to the Zipset for highest survival
and exceeded all other containers. The high elevation of Bingham
Canyon resulted in cooler temperatures, lower evapotranspiration,
and higher rainfall than other sites. Areas with poor growing season
precipitation and minimal subsoil moisture reserves fared much more
poorly than Bingham Canyon Mine. Booth Tubes were marginally
successful
(<10 percent survival) on sites receiving less than 30-cm (12-in.)
of precipitation. North Antelope Coal Mine (10 percent) and INEEL (9
percent) had the next highest Booth Tube survival while all other
sites experienced two percent or less Booth Tube survival. In
contrast, the commercially available containers with more mature
plant material experienced generally high survival on all sites with
the exception of Hanford Reach National Wildlife Refuge and the
Bureau of Land Management (BLM) Worland site. Both of these sites
experienced less than 13-cm (5-in.) of precipitation during the
October 2001 to September 2002 period.
Late frosts impacted Booth Tube seedlings at some
sites. During the planting of the Caballo, North Antelope, and
Worland-BLM sites, snow and freezing temperatures occurred for
several days during and after planting. Black spots were noted on
the dicots of Booth Tube seedlings, an indication of frost damage.
In contrast, all of the commercial container material was dormant
and immune to the effects of frost damage. Potential frost damage is
a concern for the Booth Tube planting system. Previous research has
indicated that winterfat (Ceratoides lanata), another dryland shrub,
is highly tolerant of freezing temperatures during the dicot stage
but damaged easily during the true leaf stage. An assumption for
this study is that the same would be true of sagebrush. Further
research to investigate frost tolerance of arid lands shrubs is
proposed in Phase II.
Soil type may have also played a role in low survival
of Booth Tube seedlings. Booth Tube containers removed from the
INEEL site and the Natural Resource Conservation Service sites #1
and #2 were observed to have been plugged with fine soils. During
hand-planting operations, planters tended to push Booth Tubes into
the soils, thus creating a very dense plug of fine material at the
lower end of the tube. This plug prevented root egress and likely
contributed to the death of the seedling. In contrast, the Bingham
Canyon site consisted of loose, highly drained gravels and
consequently avoided the plugging problem. The plugging problem
could easily be resolved by shortening the tube configuration to a
15-cm (6-in.) length that would allow for easier planting.
Despite overall poor survival, conditions at all
sites were severely drought impacted and some success was achieved.
The Bingham Canyon site represents what may be possible under more
moderate growing conditions typical of the areas in which the
seedlings were planted. The investigators do concede, however, that
this container type may not be suitable for areas in which the mean
average precipitation is less than 25-cm (10-in.) annually and
sub-soil moisture is absent.
Plans for Continuation
Data on survivorship and growth rates will be collected again in the
fall of 2003.
Investigators and Affiliations
Tim Meikle, Director of Research and Development, Bitterroot
Restoration, Inc., Corvallis, MT
Funding Source
U.S. Department of Agriculture Small Business Initiative Research
Grant
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