 |
Soil Ecology and
Research Group
last update October 29, 2002 |
|
BALLFIELD RESTORATION PLAN FOR THE INVASIVE
SPECIES CONTROL AND NATIVE HABITAT
ENHANCEMENT AT FLEET COMBAT TRAINING
CENTER, PACIFIC NAVAL BASE POINT LOMA
Background
The primary forms of habitat disturbance on Fleet Combat Training
Center, Pacific (FCTCP) are water erosion and exotic plant species such as
Eucalyptus spp., Acacia spp., Carpobrotus spp.
and smaller Mediterranean annual plants such as Bromus spp. and Avena
spp. Both of these disturbance types result from impacts sustained during
the construction of roads, facilities, and utility corridors. Both types of
disturbance can lead to the degradation of nearby undisturbed areas, increasing
the loss of already scarce native habitat.
The dominance of exotic plant species is apparent in the areas adjacent to
large expanses of undisturbed habitat that are susceptible to invasion by exotic
species. The western slope of the recreational field at FCTCP is an area of
several acres that is dominated by Crysanthemum coronarium, Carpobrotus
edulis, Atriplex, semibaccata, Salsola tragus, and exotic annual grasses.
The exotic Acacia cyclops that had also been dominant on the slope was removed
over the past two years, leaving much of the slope with little to no vegetation
in spots and thus making it highly susceptible to erosion.
Indications are already apparent that exotic invasion is occurring as non-native
grasses and other exotic species are beginning to appear in the native habitat
found on the slope west of the recreation field. This restoration site, called
the Ballfield site, is slightly under one acre in size and will require timely
restoration efforts in order to prevent the spread of exotic species, the subsequent
loss of additional native habitat, and the loss of soil due to the effects of
erosion. Such impacts can already be seen in the U-shaped gully located northwest
of the recreational field, where erosion gullies are forming along the northern
side.
Due to the condition of the Ballfield slope, restoration efforts will be conducted
in three phases. The first phase will be the eradication of exotic plant species.
The second phase will be the establishment of biodegradable erosion control
materials. The third phase will be the revegetation of the slope with locally
collected and grown native coastal sage scrub and maritime succulent scrub species.
The Ballfield site will be maintained and monitored for one year after planting.
Table 1 provides the proposed timeline for all restoration activities.
Table 1.
Proposed timeline for restoration activities.
| TIMELINE |
FIELD WORK |
REPORTS DUE |
| 19 July 2002 |
Determine reference site and
establish reference transect; collect
GIS data; seed collection (every
week until November 2002) |
|
| 15 September 2002 |
Greenhouse propagation of seeds |
Draft Restoration Plan
|
| 29 September 2002 |
Greenhouse propagation of seeds;
soil sampling |
Final Restoration Plan |
| 01 October 2002 |
Eradication and removal of exotic
plant species; greenhouse
propagation of seeds; soil sampling |
|
| 01 November 2002 |
Installation of jute netting;
greenhouse propagation of seeds |
|
| 15 November 2002 |
Installation of jute netting;
greenhouse propagation of seeds |
Quarterly Report |
| 15 December 2002 |
Out-planting of seedlings |
|
| 30 January 2003 |
Out-planting of seedlings;
installation of drip irrigation system |
|
| 15 February 2003 |
Supplemental irrigation of
seedlings (twice a month) |
Quarterly Report |
| 01 March 2003 |
Supplemental irrigation of
seedlings (twice a month) |
|
01 April 2003 |
Supplemental irrigation of
seedlings (twice a month) |
|
| 15 May 2003 |
Supplemental irrigation of
seedlings (twice a month) |
Quarterly Report |
01 June 2003
|
Supplemental irrigation of
seedlings (twice a month) |
|
01 July 2003
|
Supplemental irrigation of
seedlings (twice a month)
|
|
15 August 2003
|
Supplemental irrigation of
seedlings (twice a month)
|
Quarterly Report |
| 30 September 2003 |
Supplemental irrigation of
seedlings (twice a month); soil
sampling |
|
| 01 July 2004 |
|
Draft Monitoring Report |
| 15 July 2004 |
|
Final Monitoring Report |
Site Preparation
Eradication of Exotic Plant Species
Soil Ecology and Restoration Group (SERG) personnel will prepare the Ballfield
site for out-planting by eradicating all exotic plant species that occur on
or immediately adjacent to the site. Located on site are large exotic plant
species such as a palm tree, acacia trees, and Arundo donax; and smaller
exotic plant species such as C. coronarium, A. semibaccata, and S.
tragus. The larger exotic plant species will be partially cut down by hand
and the remaining stumps will be sprayed with herbicide (Roundup-Pro). The smaller
exotics will be removed by hand. C. edulis (iceplant) is also located
on site. Iceplant will be sprayed with herbicide, but then up-rooted by hand.
Located adjacent to the site (northwest side) are two Pittosporum spp.
trees which will also be removed using the same methods as the larger exotics.
Herbicide will be applied by licensed pesticide applicators only.
Erosion Control
Once all exotic plant species have been removed, the slope will be highly susceptible
to soil erosion. SERG personnel will install biodegradable erosion control materials
onto the site. Jute netting will be attached onto the slope using 6” steel
staples. Straw bale dams may be used to control erosion in the gullies forming
on the southern side of the slope. If necessary, punched straw may be used to
strengthen plant basins. The punched straw will be placed on the basin edge
facing down the slope in order to help retain water and to reduce water flow
speed.
Revegetation
Propagation of Native Plants
SERG personnel will collect seed and cuttings from Point Loma to propagate native
coastal sage scrub and maritime succulent scrub plant species in 2”, 3”
or 4” plant bands. The size of the plant band used will depend upon the
size of the plant nearing the time of out-planting. Native seeds will be propagated
in the SERG greenhouse at San Diego State University. The quantity of container
plants grown will be sufficient to achieve densities similar to those of native
plant species in undisturbed coastal sage scrub and maritime succulent scrub
near the restoration sites within three years after planting. Approximately
200 plants will need to be installed to meet this objective.
A reference transect has been established in an undisturbed habitat north of
the Ballfield site. Point-intercept monitoring was performed on this transect
line to determine the species composition of a nearby undisturbed area (see
Appendix I for results). Data collected from the transect was used to determine
the percent cover of each native plant species, which in turn helped determine
the number of each species needed to be grown and planted. Table 2 is a list
of plant species and quantities to be grown for out-planting.
Table 2.
List of species, quantities, and container sizes of plants to be grown for out-planting.
| SPECIES |
NUMBER TO BE
PLANTED |
CONTAINER SIZE |
Artemisia californica
Ceanothus verrucosus
Cneoridium dumosum
Dudleya edulis
Dudleya lanceolata
Dudleya pulverulenta
Encelia californica
Eriogonum fasciculatum
Euphorbia misera
Gnaphalium bicolor
Isomeris arborea
Lessingia filaginifolia
Lotus scoparius
Malosma laurina
Rhamnus crocea
Rhus integrifolia
Salvia mellifera
Viguiera laciniata |
15
4
20
5
5
5
13
70
2
5
11
10
10
6
2
10
2
5 |
2” x 8”
2” x 8”
2” x 8”
4” x 4”
4” x 4”
4” x 4”
2” x 8”
2” x 8”
2” x 8”
3” x 8”
2” x 8”
2” x 8”
2” x 8”
2” x 8”
2” x 8”
3” x 8”
2” x 8”
2” x 8” |
| TOTAL |
200 |
|
Out-Planting
During the rainy season of 2002-2003 (approximately 1 November through 15
February), SERG personnel will out-plant the greenhouse grown seedlings. Holes
will be dug with a shovel and, if necessary, an auger. At the time of out-planting,
each seedling will receive approximately 2 gallons of water. Depending on
the sandiness of the soil, basins may be constructed with punched straw to
retain water from rain and from irrigation. Plant protectors, either treepees
or tubex, will be placed around each seedling to discourage herbivory and
to maintain a greenhouse-like microclimate.
SERG personnel will install a temporary drip irrigation system that delivers
water directly to the basin of each seedling to improve plant survival through
the first dry season after planting. Drip lines will be temporarily connected
to an existing irrigation system, near the recreation field, to provide irrigation.
Drip irrigation will be used instead of overhead or flood irrigation to decrease
the germination of weedy species and hand watering will be avoided to prevent
soil compaction and additional soil erosion on the slope. The drip irrigation
system will be removed at the end of the first year after planting.
Maintenance and Monitoring
The Ballfield site will be maintained and monitored for one year after planting.
From February 2003 to February 2004, the plants will be watered twice each month,
as necessary, and each basin will receive approximately 1 gallon of water. Any
damage to the drip irrigation system will be repaired and the site monitored
for reoccurring weeds. Weeds will be removed by hand or sprayed with herbicide.
Monitoring will also consist of quantifying the survival of out-plantings, determining
the cover of plant species at the site, qualitatively assessing the growth of
out-plantings via photo documentation, and determining the need for additional
weed control.
In addition, soil samples randomly collected will be tested for texture, organic
matter, pH/EC, percent moisture, phosphorus, and nitrates. Samples will be collected
and tested in September 2002 and September 2003. Results will be used to determine
the physical and chemical composition of the soil and to determine which plant
species is viable in such soil.
Success Criteria
The success criteria will be determined by percent plant survivorship. At the
end of the monitoring period, container plant survivorship will be 60%. If survivorship
is below 60%, then SERG will plant additional container stock and monitor the
site for another year to ensure that survivorship reaches 60% of the number
of plants installed during the first planting season.
Implementation Report (September
29, 2003)
