Treesearch

Monitoring is essential in understanding the success or failure of a conservation project and provides the information needed to conduct adaptive management. Although there is a large body of literature on monitoring design, it fails to provide sufficient information to practitioners on how to organize and apply monitoring when implementing landscape-scale conservation projects. We describe a decision framework currently being developed by The Nature Conservancy. It can be used to help set monitoring goals, prioritize monitoring efforts, and select monitoring metrics. Monitoring goals...

The wholesale destruction of oak woodland by North American settlers in the Santa Clara Valley is attested in early county histories and other sources. Early plats and field notes by government and private surveyors, which are the most useful kind of sources as to the distribution and extent of the lost oak groves, still leave serious gaps in our knowledge. A further source of information is the dangerous legacy left behind in the soil by the original groves when they were chopped and the roots left to rot. The honey fungus or oak root fungus (Armillaria mellea) became a serious problem to...

Age structure and growth of California black oak (Quercus kelloggii) was determined from tagged trees at four 26.1-acre study stands in Placer County, California. Stands were dominated by large diameter (>20 inch dbh) California black oak and ponderosa pine (Pinus ponderosa). Randomly selected trees were tagged in June-August 1998 and harvested under a group selection timber harvest in October-November 1998 and May-June 1999. Trees averaged 148 years of age (range = 58 to 356 years, n = 108), and ages differed among the four stands (P < 0.006). stands had uneven distributions of tree ages,...

Blue oak savannas were found to be substantially more diverse at all scales from localized point diversity to the community scale, than higher elevation shrubland and coniferous forests in the southern Sierra Nevada. Also, alien plants were more diverse and represented a substantial fraction of the understory flora in these blue oak savannas, comprising three-fourths of the species at the smallest scale (1-m2) and about half at the largest scale (1,000-m2). Either alien invasion has greatly increased species diversity in these savannas or it has displaced native annuals as opposed to...

The interlinkage of privately owned foothill oak woodlands and federal grazing permits in the central Sierra Nevada is examined. Knowledge of the viability of the range livestock industry is important to large-scale conservation of hardwood rangelands in the Sierran foothills. Because ranches in the Sierra often use USDA Forest Service grazing allotments, efforts at land conservation may be influenced by Forest Service grazing decisions. We conducted in-depth interviews with Sierra foothill ranchers with federal grazing permits, asking what they would do if their allowable forage use was...

In this study livestock distribution on the landscape was mapped during two seasons, summer and winter, for two years to determine where livestock congregate and to model factors that influence livestock distribution. Two small herds of cows were observed in separate range units on the San Joaquin Experimental Range for a total of twenty-four 24-hour observation periods to ascertain daily movements and activities. Treatments involving water placement and the use of supplemental feeding sites were implemented to judge the effects of these management techniques on cattle distribution. Animal...

From 1994 to 1998 we documented sediment transport dynamics and sources in a 137 ha grazed hardwood rangeland watershed on granitic soils at the San Joaquin Experimental Range in Madera County. Sediment transport for this watershed was determined by measuring total suspended solids, bedload and flow at an H-flume installed in 1994. Sediment movement as bedload is the primary means of sediment transport in this watershed, with minimal transport of suspended solids. This is attributed to the large sediment particle size and low stream power characteristic of this low gradient intermittent...

Long-term residual dry matter mapping on the San Joaquin Experimental Range provides a working example of this monitoring technique for grazing management and research. Residual dry matter (RDM) is the amount of old plant material left on the ground at the beginning of a new growing season. RDM indicates the previous season’s use and can be used to describe the health or condition of annual rangelands. An RDM evaluation is made before the first effective fall rains, usually in late September or early October. Direct clipping and weighing, comparative yields, or photo standards are used to...

Garry oak (Quercus garryana) was once a dominant habitat type on southeastern Vancouver Island, British Columbia but urbanization has severely fragmented and reduced its occurrence. This study tests whether bird abundance in remnant patches of Garry oak and adjacent Douglas-fir (Pseudotsuga menziesii) is related to Garry oak volume, patch size or urbanization. Breeding bird populations were surveyed at seven Garry oak sites and four adjacent Douglas-fir sites. Relationships between environmental variables and abundance of 17 species of birds were inferred by selecting the best linear...

We investigated arboreal removal and insect damage to acorns in an undisturbed oak woodland in central coastal California. Arboreal seed removal was determined for four to eight individual Quercus lobata trees over a period of 14 years by comparing visual estimates of the acorn crop with the number of acorns caught in seed traps. Insect damage was assessed by sampling acorns from trees of all three species of oaks common in the study site (Quercus lobata, Q. douglasii, and Q. agrifolia). Patterns were generally similar for both sets of data: more acorns, but a smaller proportion of the...