CHAPTER 4 - MONITORING HARDWOOD RANGELANDS

---

In order to evaluate the sustainability of our oak woodland ecosystems, we must be able to identify trends in woodland structure, health, resource use, and other factors that affect long-term viability. To achieve this, the California Dept. of Forestry and Fire Protection assumed responsibility for monitoring changes in hardwood range as part of its responsibility to assess the extent and availability of wildland resources in California. CDF developed a long-term strategy for monitoring the statewide extent and distribution of hardwoods, and implemented various measures to detect changes over short-term intervals.

In producing the new polygon maps, Pacific Meridian determined that there were more acres of hardwoods than previously detected, particularly in the North Coast and northern Sacramento Valley. They show increases in blue oak, blue oak-grey pine, and montane hardwood cover types, and also in the middle crown closure classes.

Long-term monitoring
The long-term effort began with the development of a baseline coverage of California's oak woodlands based on 1981 aerial photography. Under contract to CDF, California Polytechnic Institute mapped hardwood areas up to 5,000 ft in elevation, using six major oak vegetation types and four tree canopy classes. The minimum mapping unit was 40 acres (that is, areas or stands under 40 acres were not mapped). The program intent was to develop subsequent maps that could be compared with the baseline map to detect changes. Individual maps were generated for all counties with hardwood range and distributed to county planning offices.

In 1990, CDF contracted with Pacific Meridian Resources for its second statewide hardwood rangeland map. The objectives of this project were 1) to create a current map of hardwood rangelands using 1990 satellite imagery, 2) to assess the accuracies of the resulting map and the earlier map, 3) to test a computerized method for detecting changes in hardwood cover, and 4) to produce a vegetation map or riparian zones along perennial streams.

The new map shows more acreage in some hardwood cover types and denser canopy classes than the 1981 map. This difference was attributed to inaccuracies detected in the baseline maps and also to differences in mapping methodologies, rather than actual changes in hardwood cover. Due to these factors, the contractor determined that it could not reliably compare the two maps to assess hardwood change.

The new maps contain six layers of information in a digital format for use in a Geographic Information System. A land cover map composed of satellite pixel data (areas 30 in x 30 in or about 1/5 acre in size) is available. It has been classified into 12 categories, including six hardwood and six non-hardwood types. Two tree crown closure maps were also created, one based on the original classification developed at Cal Poly, and the other consistent with that of the Wildlife Habitat Relationships (WHR) systems. In addition, a map of hardwood tree sizes (greater than or equal to 12 inches dbh, or less than 12 inches dbh) and a riparian vegetation map were also developed. Lastly, an updated polygon map was generated.

Due to apparent omission errors in the first map, Pacific Meridian examined areas beyond the 5,000 foot elevation level. They determined that there was substantial additional hardwood acreage outside the original area mapped by Cal Poly; however, they did not ground truth this area.

In producing the new polygon maps, Pacific Meridian determined that there were more acres of hardwoods than previously detected, particularly in the North Coast and northern Sacramento Valley. They show increases in blue oak- blue oak-grey pine, and montane hardwood cover types, and also in the middle crown closure classes. Accuracy assessments of canopy closure in the original and new polygon maps indicate that both maps underestimate canopy closure.

The contractor also tested a computerized method for estimating hardwood cover change by comparing pixel data from two satellite images from different years in parts of Tehama and Shasta counties. While the project indicated areas of potential canopy removal in a number of places, the final interpretations were not entirely consistent with harvest information gathered using airplane reconaissance. Therefore, we recommend that this method be accompanied by adequate field support or local expertise to verify the results.

Short-term monitoring effort
As part of its efforts to keep informed of harvest behavior on wildlands and of areas of intensive activity impacting hardwood values, CDF implemented several short-term harvest detection methods. The most recent consisted of visual estimates of oak harvesting over a period of three years between 1989 to 1992. Aircraft was used to look for harvesting in over 35 counties. This effort, described in earlier progress reports, found an annual average of nearly 6,000 harvested acres. Most of the harvesting was concentrated in the northern Sacramento Valley, with about 60% of the total occurring in Tehama and Shasta. The method was not useful for detecting conversions for development and only marginally useful for agricultural conversions. Over the three years harvesting trends appeared to be slightly downward, with the same basic geographic pattern of activity.

Developing an Alternative Monitoring Approach
Due to the problems associated with changing technologies, CDF has not been able to definitively estimate changes in hardwood range over the last decade. The short-term monitoring results, generated by an informal method, are of unknown accuracy and precision. Monitoring data is critical, nonetheless, to assessing the sustainability of oak woodland ecosystems. Monitoring is essential to tracking changes in the system and to providing for adaptive policy making and resource management.

In order to address this need, CDF is currently reevaluating its monitoring strategy. The purpose of monitoring should be to produce timely data which will be useful to state and local interests. These include CDF concerns about assessing statewide trends in hardwood rangeland ecosystems, and concerns of planners, resource managers, landowners, industry, watershed groups, and others about land use planning, biological diversity, resource management, and sustainable economic development.

While CDF has assumed sole responsibility for the monitoring of hardwood rangelands in the past, approaches that increase local involvement are needed to improve the accuracy of data and, perhaps more important, the relevancy of this information. A survey by the Oak Foundation in 1994 found that almost half of the county planners interviewed were not aware of the hardwood maps sent by CDF. This is probably because they had not participated in the process, the data had not been collected to meet specific local needs, and the information was not introduced in a context or timeframe relevant to their activities.

The following alternatives represent different approaches to monitoring:

1. Continue periodic statewide monitoring using satellite imagery, distribute maps of existing hardwood rangelands, and identify potential changes since the last monitoring effort. This would require purchase and processing of satellite imagery, contracted fieldwork for accuracy assessment, and outreach. The benefits would include data of known and uniform accuracy, and ensure statewide coverage. However, the cost would be very high and the added disadvantages include lack of local buy-in and use of the data, and lack of timely delivery.
   
   
2. Continue periodic statewide monitoring in key areas. The requirements for this alternative would he similar to but less expensive than those Alternative 1, since monitoring would be focused on areas where previous efforts indicated the greatest pressures by harvesting, development or agricultural conversions. Local participation and relevance to local issues would still be missing.
   
   
3. Provide a tiered approach to monitoring key areas by providing data for local groups to refine. This would essentially provide maps or spatial data along with computer-based interpretations of areas of apparent hardwood change to local groups which would then verify or refine the information through fieldwork or with local expertise. CDF might contract with local entities to accomplish this, and would incorporate their interpretation results into any statewide assessment efforts. The benefits of this approach to local groups include the use of this process to address additional information needs if desired; the ability to speak for the accuracy of the data; and the opportunity to bring it to bear on local planning and management activities in a timely fashion. Disadvantages include incomplete state coverage and variable accuracy.
   
   
4. Opportunistic monitoring. CDF would provide funds or data toward state or local efforts to incorporate oak woodlands into other monitoring efforts. This alternative would require CDF to explore opportunities for integration with other statewide monitoring programs by federal or state agencies, or for funding or assisting localized monitoring or assessment activities (at county or regional scales). The benefit of these approaches is that CDF would eliminate in-house data development and processing costs, and oak protection concerns would be incorporated into other assessment/planning activities. The disadvantages would be incomplete statewide monitoring coverage and variable methodologies and accuracies.
   
   

CDF is pursuing a combination of strategies 3) and 4). We have begun to work with groups, such as RCDs or local oak committees in the Sierra and northern Sacramento, to evaluate local interest in hardwood data and locally-based options for monitoring. We are also considering how oak monitoring may be incorporated into an effort such as the GAP analysis. Through these efforts we hope that information about oak ecosystem trends may enhance decision making in the areas of land use planning, watershed management, biodiversity protection, and other efforts affecting private hardwood rangelands.


Monitoring to Assess the Effectiveness of Hardwood Conservation Efforts

Monitoring the status and condition of California's hardwood-dominated habitats is a major focus of the Integrated Hardwood Range Management Program (IHRMP). To date, monitoring efforts have primarily focused on determining abundance and distribution of these habitats, as well as assessing short-term areal habitat changes due to various land uses. These efforts have produced considerable amounts of important information useful for hardwood conservation efforts. Yet, this information cannot be used solely to evaluate success of any conservation effort because of natural and human-influenced dynamics of hardwood habitats, limitations with monitoring information, continued losses and degradation of hardwood habitats, and paucity of specific hardwood conservation strategies.

The California Departments of Fish and Game and Forestry and Fire Protection, in cooperation with the IHRMP, are responsible for these monitoring efforts. These efforts are extremely important due to continued and perhaps increasing concern about the declining status and condition of California's hardwood resources and the associated economic, social, ecological, and aesthetic values.

In addition, current monitoring efforts have some weaknesses when used to determine whether the IHRMP is meeting its guiding mission "to maintain and where possible increase the acreage of California's hardwood range resource to provide wildlife habitat, recreational opportunities, wood and livestock products, high quality water supply, and aesthetic value." Furthermore, the California Board of Forestry (Board) continues to favor hardwood conservation strategies based on research, education, monitoring, and local derivation and control, rather than statewide regulations. Also, monitoring hardwood resource status and the IHRMP is stipulated under the newly adopted Hardwoods Policy jointly approved by the California Fish and Game Commission and Board. The California Departments of Fish and Game and Forestry and Fire Protection, in cooperation with the IHRMP, are responsible for these monitoring efforts. These efforts are extremely important due to continued and perhaps increasing concern about the declining status and condition of California's hardwood resources and the associated economic, social, ecological, and aesthetic values.

For these reasons, more diligent and ecologically-based monitoring processes are needed to more fully evaluate the effectiveness of hardwood conservation efforts. Monitoring under the broad mission of the IHRMP and the Joint Hardwoods Policy should occur under two major areas: (1) status, trend, and condition of the hardwood resource; and (2) effectiveness of hardwood conservation efforts. These two areas are not mutually exclusive because they depend on each other. Effectiveness of conservation efforts cannot be developed or fully measured without some information on status, trend, and condition. Also, resource inventories would be of rather limited application if they were not intended to evaluate the conservation effort success.

Monitoring efforts must be ecologically-based because hardwood habitats are in fact ecological systems on which much of the widely acknowledged economic, social, ecological, and aesthetic values depend. Therefore, monitoring and conservation efforts should focus on key ecological parameters that afford land owners and managers, resource professionals, decision makers, and the general public with the opportunity to evaluate the condition of resources and success of conservation efforts. Monitoring is also the key feedback process that allows modification, revision, and/or redirection of management and conservation strategies if these efforts are not meeting defined missions, goals, and objectives.


The following section focuses mostly on aspects of monitoring efforts designed to assess effectiveness of hardwood conservation strategies developed per the Board's continued emphasis on local development and control of strategies and actions. These components as itemized below are generic and could be easily applied to a variety of habitat types and conservation efforts throughout California. In addition, they are well-founded in the scientific literature (see selected references). The primary goal of any hardwood conservation effort should be long-term conservation of hardwood-dominated ecosystems. The following goals and criteria, while certainly not definitive nor infeasible, could be part of a monitoring effort specifically designed to evaluate conservation strategies. Defined parameters and resource levels must be individually developed for each strategy and are beyond this paper's scope. However, what follows is a rather coarse template.


OVERALL GOALS (Desired Outcomes from Conservation Strategies)

1. Efforts should result in long-term conservation and perpetuation of hardwood-dominated ecosystems and their attendant plant and animal resources.
   
   
2. Efforts should result in animal and plant populations and communities, as well as hardwood-dominated ecosystems that have long-term sustainability, functioning, and viability.
   
   
3. Populations of threatened and/or endangered animals and plants shall be protected and perpetuated in these ecosystems.
   
   
4. These goals can be achieved under a variety of compatible land use practices, including livestock grazing, residential and commercial development, private and public lands hunting, agriculture, firewood and lumber harvesting, land acquisition, easements, etc.
   
   
5. Efforts should be used to make land-use decisions by local governments, private landowners, resource agencies, etc.
   
   
6. Efforts should result in periodic assessment and long-term monitoring of defined ecosystem parameters, and responsible parties shall be identified and held accountable for assessment and monitoring. Monitoring programs should be designed to allow for modification and improvement of conservation efforts, if necessary.
   
   
7. Abundance, distribution, functioning, and integrity of these ecosystems will not be substantially reduced, degraded, or lessened and increases and improvements are possible goals for these efforts.
   
   

SPECIFIC CRITERIA FOR EVALUATING SUCESS OF STRATEGIES

1. Efforts are based on biological and ecological principles.
   
   
2. All spatial scales (e.g., single tree, stand, ecosystem, landscape, etc.) can be adequately addressed and conserved.
   
   
3. All biological scales (e.g., genetic, population, community, faunal assemblages) can be conserved at viable levels.
   
   
4. Key ecological processes and values (e.g., regeneration, water quality, disturbance regimes, etc.) are considered and accounted for.
   
   
5. Random (stochastic) events (e.g., fire, floods, droughts, etc.) are recognized, and conservation efforts result in ecosystems that can respond and recover from these events.
   
   
6. Multiple habitats and ecosystems are recognized and considered. That is, while hardwood-dominated habitats may be the focus, entire ecosystems and landscapes and their component habitats including woodlands, savannahs, grasslands, riparian areas, shrublands, wetlands, etc. should be addressed and conserved.
   
   
7. Assessments of resource abundance, distribution, condition, and trend is accomplished. These assessments should be as accurate and broad-based as possible given available staff and funding. Assessments provide baseline and monitoring data against which future conditions are evaluated when land use decisions are being made and conservation success is being determined.
   
   
8. Measurable and unambiguous resource attributes and thresholds are identified, and these attributes are used when making land use decisions.
   
   
9. All possible affecting land uses are recognized and addressed.
   
   
10. Efforts should encourage and/or promote conservation across multiple ownerships and jurisdictions which do not constrain biological systems.
    
    
11. Efforts are binding so that decision-makers and other responsible parties are accountable for their actions. This does not necessarily infer regulations.
    
    
12. Monitoring and feedback mechanisms exist so that the effectiveness can be evaluated and modified if necessary.
    
    

Many of these criteria, if adopted and developed in greater detail, may be sufficient for a monitoring program. However, baseline resource conditions with desired future conditions must be explicitly defined to measure against resource assessments. Data must be consistently gathered to assess status and trend. Too often, conservation strategies are developed and implemented with relatively little effort and resources devoted to monitoring. The result could be status quo where it is difficult to reliably determine success or failure. Most implemented strategies have success as the expected outcome, yet poor or unavailable monitoring information probably will not allow anyone to unequivocally claim success.