Columbia Wash

Soil Ecology and Research Group

last update January 13, 2005

IMPLEMENTATION REPORT

COLUMBIA WASH, LANGFORD ISLAND, AND LANGFORD WASH
NATIONAL TRAINING CENTER
FORT IRWIN, CA 92310

The National Training Center at Fort Irwin, CA is a training facility for the United States Army. Located 35 miles northeast of the city of Barstow, California, Fort Irwin occupies an area of nearly 643,000 acres within the Mojave Desert. Training activities conducted at the installation provide units and commanders the opportunity to practice large-scale war fighting skills in a realistic environment. Ground maneuvers, live-fire exercises, and force on force activities damage the native vegetation of the Mojave Desert creosote/bursage scrub habitat, which in turn causes dust and erosion problems.

The Integrated Training Area Management (ITAM) Program is responsible for land management and rehabilitation of disturbed areas on the post. Projects proposed by the ITAM program combine both re-vegetation and erosion control to minimize the environmental impacts of training activities. Dust contributes to poor air quality as well as reduced visibility. Controlling levels of particulate matter less than 10 microns (PM 10) is of particular importance, as long-term exposure to these tiny particles is a health risk to people both on the base and in surrounding communities.

The purpose of this project at Columbia Wash, Langford Island, and Langford Wash is to reinforce corners of heavily used trails to prevent further widening and to encourage the use of existing trails. Berms were created at all three sites to define trails, aid in moisture retention, and deter water erosion. Major trails at all sites were graded to encourage their use. Dust created by traffic along the trails at these sites poses a hazard during training activities due to reduced visibility and also contributes to off-post air quality issues. Revegetation of sandy areas with greenhouse-grown native shrubs will reduce dust and improve air quality, particularly in the Langford Wash area, which was almost completely barren, as well as providing protection for established shrubs within the sites.

Columbia Wash
The Columbia Wash site is an approximately 20 acre area bordered along the northeast by the Red Pass MSR and along the southeast by the Columbia Wash MSR (Figure 1). The site is 38.5 kilometers from the Cantonment area and is centered at UTM Grid Coordinates 557926 E 3907186N, near the eastern border of Fort Irwin. The site is dissected by one well-defined trail running north to south, one running northeast to southwest, and three running east to west. There is established native vegetation on the western edge of the site that is being reduced by vehicle traffic along the trails through the site. The interior and eastern edge of the site are largely bare except for native ((Dicoria canescens, Ambrosia acanthicarpa ) and exotic (Salsola tragus, Brassica tournefortii , Schismus barbatus) annual species.

The restoration design for the site (Figure 2) involved grading the well-defined north to south trail through the site to encourage its use. Berms were built along the edges of all minor trails to discourage the widening of these trails and to divert traffic onto the MSRs. Pairs of greenhouse-grown native shrubs were transplanted in basins along all trails to create more permanent boundaries and protect established shrubs within the site.

Site-specific information includes soil type and vegetative species composition. The soil is of the Arizo series and consists of gravelly sandy loam with moderate to high compaction (See Appendix A for a more complete soil series description). Native species found on the site include Larrea tridentata (Creosote bush), Hymenoclea salsola (Cheese bush), Ephedra nevadensis (Mormon tea), and Ambrosia dumosa (Burro bush).

Langford Island/Langford Wash
The Langford Island and Langford Wash sites have a combined area of approximately 30 acres bordered on the north by Langford MSR (Figure 3). The sites are 13.7 kilometers from the Cantonment area, southeast of Langford Dry Lake. Langford Island is centered at UTM Grid Coordinates 538669 E 389371 N and is dissected by many small trails running in all directions. There is established native vegetation on most of the site that is being reduced by trail use. Langford Wash is centered at UTM Grid Coordinates 538841 E 3894114 N and is dissected by one well-defined trail running east to west near the southern edge of the site and three smaller trails running various directions through the site. Langford Wash is virtually barren of established native vegetation.

The restoration design for Langford Island (Figure 4) involved grading major trails to encourage their use and ripping minor trails to discourage their use. Berms were built on the edges of all trails to be planted as well as along trails at major intersections to the northwest and the south of the planted area in order to discourage the widening of these trails and to divert traffic away from the corners and smaller trails. Pairs of greenhouse-grown native shrubs were transplanted in basins along four of the trails to create more permanent boundaries and protect established shrubs within the site.

The restoration design for Langford Wash (Figure 5) involved grading major trails to encourage their use and building berms to keep traffic on the main trails and out of the central area of the site. Pairs of greenhouse-grown native shrubs were transplanted in basins along the edges of the five sections defined by the berms in an effort to create more permanent boundaries and improve air quality in the immediate area by keeping traffic out of the barren, sandy, central area of the site.

Site-specific information includes soil type and vegetative species composition. The soil at the Langford Island site is of the Gravesumit-Cajon-Livefire complex and consists of mixed coarse-loamy soil with moderate to high compaction (See Appendix A for a more complete soil series description). The soil at the Langford Wash site is of the Arizo series and consists of gravelly, sandy-loamy soil with high compaction (See Appendix A for a more complete soil series description). Native species at both Langford Island and Langford Wash include Larrea tridentata (Creosote bush), Hymenoclea salsola (Cheese bush), Ephedra nevadensis (Mormon tea), and Ambrosia dumosa (Burro bush).

Columbia Wash
Site Preparation
Site preparations occurred between 21 October 2003 and 18 December 2003. Figure 6 shows parts of the Columbia Wash site prior to implementation. A Caterpillar 140H motor grader ripped to the depth of 1 foot the edges of all trails to be in order to reduce compaction (Figure 7). A number of minor were also ripped to discourage vehicle traffic. The grader was also used to smooth and compact the major north-south trail through the site and to build a total of 5,200 feet of berms, approximately 2 - 3 feet high, along all trails within the site to divert vehicle traffic from the revegetation areas. The berms along the Red Pass and Columbia Wash MSRs were built several feet out from the edge of the revegetation area to discourage further widening of the MSRs. A mechanical trencher was used to create 7 100-foot trenches along the eastern edge of the site, approximately 3 inches wide and 20 inches deep, and a 100-foot length of 3-inch perforated drain pipe was installed in each trench and buried (Figure 8). Both ends of each pipe were capped and secured to a 3-foot length of rebar with baling wire in an effort to keep out sand and wildlife.

Figure 6. Columbia Wash prior to implementation: View from northern end facing south (A) and the view from central area facing south (B).

Figure 8. Trenching perforated pipe line (A) and installing perforated pipe (B) at Columbia Wash.

Planting
Holes for outplanting were dug with a power auger. Planting began 21 October 2003 and concluded 18 December 2003 (Figure 9). All holes were pre-watered with approximately 3 gallons of water with an additional 2 gallons of water applied after planting. Vitamin B-1 solution was added to the water used during planting in order to reduce transplant shock. Native shrubs were planted in pairs, and a basin approximately 6 inches high was created around each pair. The shrubs were initially protected with a combination of Treepee Quicone® and Tubex® plant protectors. The majority of the Tubex was removed and replaced by Treepees before planting was completed because the Treepees provided more light and space for plant growth, were easier to install, and are more stable in windy conditions than Tubex.

A total of 754 native desert shrubs were transplanted. The shrubs were positioned around the edges of the trails defined by the berms. Along the perforated drain pipes 14 - 15 shrubs were transplanted with a small, circular basin around the base of each. Each plant has been watered with one to two gallons per month from January 2004 through July 2004, with the exception of January and March, which received adequate rainfall to make additional watering unnecessary. Table 1 lists the species composition of shrubs planted at the Columbia Wash site.

Langford Island
Site Preparation
Site preparations occurred on 18 December 2003. Figure 10 shows parts of the Langford Island site prior to implementation. A Caterpillar 140H motor grader ripped to the depth of 1 foot the edges of all trails to be in order to reduce compaction . The grader was used to smooth and compact the major trails through the site to encourage their use and to build a total of 2,500 feet of berms approximately 1 - 2 feet high along all trails to be planted and at two major intersections to the northwest and the south of the planted area in order to divert traffic away from the corners and smaller trails. Minor trails within the site were ripped to discourage their use.

Figure 10. Three views of the Langford Island site prior to implementation: facing north (A), facing southwest (B), and an intersection within
the site to be reinforced (C)

Planting
Holes for outplanting were dug with a power auger. Planting began 18 December and concluded 19 December 2003. All holes were pre-watered with approximately 3 gallons of water with an additional 2 gallons of water applied after planting. Vitamin B-1 solution was added to the water used during planting in order to reduce transplant shock. Native shrubs were planted in pairs, and a basin approximately 6 inches high was created around each pair. The shrubs were protected with Treepee Quicone® plant protectors.
A total of 204 native desert shrubs were transplanted. The shrubs were positioned around the edges of the trails defined by the berms (Figure 11). Each plant has been watered with one to two gallons from January 2004 through July 2004, with the exception of January and March, which received adequate rainfall to make additional watering unnecessary. Table 2 lists the species composition of shrubs planted at the Langford Island site.

Langford Wash
Site Preparation
Site preparations occurred on 19 December 2003. Figure 12 shows parts of the Langford Wash site prior to implementation. . A Caterpillar 140H motor grader ripped to the depth of 1 foot the edges of all trails to be in order to reduce compaction . The grader was also used to smooth and compact the major trails through the site to encourage their use and to build a total of 6,000 feet of berms approximately 1 - 2 feet high the edges of the areas to be planted in order to divert vehicle traffic from the revegetation areas. Minor trails within the site were ripped to discourage their use.

Figure 12. Two views of Langford Wash prior to implementation: facing northwest (A) and facing southwest (B).

Planting
Holes for outplanting were dug with a power auger (Figure 13). Planting began 6 January and concluded 13 January 2004 (Figure 14). All holes were pre-watered with approximately 3 gallons of water, with an additional 2 gallons of water applied after planting. Vitamin B-1 solution was added to the water used during planting in order to reduce transplant shock. Native shrubs were planted in pairs, and a basin approximately 6 inches high was created around each pair. The shrubs were protected with Treepee Quicone ® plant protectors.

A total of 905 native desert shrubs were transplanted. The shrubs were positioned around the edges of the areas defined by the berms (Figure 15). Each plant has been watered with one to two gallons February through July 2004, with the exception of March, which received adequate rainfall to make additional watering unnecessary. Table 3 lists the species composition of shrubs planted at the Langford Wash site.

Figure 15. Three views of Langford Island after planting: section 4 (A), sections 1 and 2 (B), and section 1 (C).

Columbia Wash
Planting
One week after the completion of planting at Columbia Wash, a large storm caused significant damage to the site. A total of 42 plants were missing. The missing plants were subtracted from the survival calculations. The overall 6 month survival rate for the Columbia Wash site was 89.9% (Table 4). Chilopsis linearis and Lycium andersonii both had 100% survival rates. Atriplex canescens, Ambrosia dumosa, Ephedra nevadensis, Hymenoclea salsola, Larrea tridentata, and Sphaeralcea ambigua all had survival rates over 90%. Brickellia incana and Eriogonum fasciculatum had survival rates between 80% and 90%. Encelia frutescens and Senna armata had the lowest survival rates at 72.2% and 30.0%, respectively. Figure 16 shows two views of Columbia Wash six months after implementation.

Erosion Control
The major storm one week after planting did significant damage to the berms at Columbia Wash (Figure 17, 18). Despite the fact that the berms were built higher than usual (2 - 3 feet rather than 1 - 2 feet), the heavy and rapid water flow resulting from the storm almost completely washed away the berms along the newly-graded north-south trail through the site. Berms closing off natural watercourses in several other areas within the site sustained major damage as well. In a count and damage assessment conducted two weeks after the storm, 42 plants were completely missing. A large number of plants were buried or partially buried, however, the vast majority of these plants were found to be alive when the accumulated sand was removed. The high survival rate among the plants remaining after the storm indicates that the undamaged berms and basins were successful in retaining water for the plants.

Columbia Wash also experienced a large amount of vehicle damage after the storm (Figure 19). The fact that the destruction of the berms made it much more difficult to distinguish the major trails throughout the site was likely a contributing factor to the subsequent vehicle damage. This idea is supported by the observation that areas of water damage and vehicle damage coincided throughout much of the site (Figure 20). Repairs to some of the more minor water and vehicle damage to the berms was completed on 6 February 2004, but the water damage to the berms along the graded north-south trail was too extensive to repair with hand tools. The other winter and spring storms did not significantly increase the damage at Columbia Wash.

Langford Island
Planting
The overall 6 month survival rate for the Langford Island site was 98.0% (Table 5). Ambrosia dumosa, Encelia farinosa, Ephedra nevadensis, and Eriogonum fasciculatum all had 100% survival rates, while Hymenoclea salsola and Larrea tridentata had survival rates of 95.2% and 98.0%, respectively. Two views of the Langford Island site six months after planting are shown in Figure 21.

Erosion Control
The very high survival rate at Langford Island indicates that the berms and basins were quite successful in retaining water for the plants. The berms built at the Langford Island site were also moderately successful in keeping vehicle traffic out of the planted areas. Most of the vehicle damage was found at the corners of the trails, likely resulting from the narrowness of most of the major trails within the site (Figure 22). During watering, SERG personnel often found it difficult to make turns without running over the corners of the berms . Along one trail, the berm and several plants in a row were run over, however none of these plants were actually killed (Figure 23). Repairs to much of the vehicle damage were completed during the first watering trip, but more damage has been observed in the same areas on subsequent visits.

Langford Wash
Planting
The overall 6 month survival rate for the Langford Wash site was 92.7% (Table 6). Atriplex polycarpa, Ephedra nevadensis, Kraschinninikovia lanata, Larrea tridentata, and Thamnosa montana all had 100% survival rates. Ambrosia dumosa, Encelia farinosa, Encelia frutescens, Eriogonum fasciculatum, Hymenoclea salsola, Isomeris arborescens, Lycium andersonii, Prosopis glandulosa, Salazaria mexicana, Senna armata, and Sphaeralcea ambigua all had survival rates of 90% or higher. Atriplex canescens and Lepidium fremontii had survival rates between 80% and 90%. Chilopsis linearis and Psorothamnus arborescens had the lowest survival rates at 68.3% and 53.8%, respectively. Figure 24 shows two views of Langford Wash six months after implementation.

Erosion Control
The high survival rate at Langford Wash indicates that the berms and basins were largely successful in retaining water for the plants. The berms around the planted areas also appear to have been largely successful in deterring vehicle traffic so far. Very little damage was found during the first watering trip, although in at least one instance, a vehicle had driven directly through the center of one of the sections (Figure 25). This is assumed to have been intentional, as there was no obvious reason for the vehicle to have taken that course. The small amount of damage was repaired during the first watering trip, but additional damage has been observed on all subsequent trips. Overall however, the berms appear to be acting as a successful deterrent.

Survival is satisfactory at all three sites 6 months following the completion of planting. All three sites have survival rates far above the 70% survival established as success criteria, with survival at the Langford Island site being the highest at 98.0%. The high survival rates can be attributed to several factors, the first of which is that all shrubs were planted between October and January when soil and air temperatures were still moderate. The soil at all three sites was relatively non-compacted, as well as being deep and sandy and therefore ideal for water absorption. Rainfall through the winter and spring was adequate, well-distributed, and, with the obvious exception of the Christmas storm that damaged Columbia Wash, of moderate enough strength to provide water to the plants without damaging or burying the plants or running off and causing erosion to the basins and berms.

Based on the problems experienced at Columbia Wash, it is recommended that future restoration projects not be located in such high-risk areas as large washes at the intersection of major roads. From a cost-effectiveness perspective, large washes and major intersections are both hazardous positions for revegetation and erosion control efforts. Combining these risk factors makes it nearly inevitable that substantial damage to the site will occur. Because the Columbia Wash site covers a large area and is dissected by several small trails, additional Seibert stakes and/or further trail closures would likely be useful in reducing future vehicle damage.