Chapter 5 Forest Practices Alan Vyse, Dennis Bendickson, Kirsten Hannam, Davide M. Cuzner, and Kevin D. Bladon INTRODUCTION The forests of British Columbia have had, and con- Where there is too little water, or too much, forests tinue to have, a powerful influence on the lives of do not grow. And within the range of adequate the province’s residents. Most British Columbians water, small changes have profound influences on live surrounded by forests. Their houses are largely the forest, its structure, and the constellations of built of wood and their employment often depends organisms that live within its enveloping sphere of on some aspect of the forest industry, whether they influence. Those same water supplies from forested live on a farm, in a logging town, or within the me- mountain slopes support fish populations of im- tropolis of Vancouver. Young and old recreate in the mense size. As management of forests has evolved, forest, whether on ski runs or by lakeshores. Creative care for the water resource, and its associated fisher- artists have drawn inspiration from the wild for- ies, has moved from a marginal issue to a touchstone est and the busy goings-on of a forest industry set for efforts to modify forest practices (Chapter 1, within the stunning backdrop of ocean and moun- “Forest Hydrology in British Columbia: Context and tains. Children learn that many provincial emblems History”). Public concerns about drinking water are derived from the forest, including the dogwood and fish habitat played a major role in this transfor- flower, the western redcedar tree, and the Steller’s mation. Contentious issues ranged from the widely Jay, a noisy, blue-black, forest-dwelling bird. For all publicized and intense battles over logging in the British Columbians, their experience of the forest is Greater Vancouver and Victoria watersheds (which inextricably linked with water. ended in victory for the anti-logging side) to con- From a human perspective, water supplies for frontations over logging and water quality in smaller communities of every size flow directly from for- communities throughout the Interior and, in par- ested mountain slopes. Watercraft fashioned from ticular, in the Slocan Valley where they persist. Very trees were used by Aboriginal communities, and recently, the impact of the mountain pine beetle on then European explorers, to traverse the lakes and forests and hydrological processes has reawakened rivers of the Interior and the inlets of the Coast. concerns about the management of water through- Early commercial use of the forest relied on water out the province. for power and cheap transportation both by the This chapter shows how some forest management ocean and along the inland waterways. Flumes, river practices in British Columbia may affect hydrologi- driving, paddlewheelers, and ocean tugs all played a cal processes. Harvesting and regeneration systems major role in British Columbia’s forest history. are described followed by the transportation of wood Past exploitation of the forest and the transition to from the forest to processing sites. The chapter ends forest management is also closely linked with water. with a brief overview of provincial forest policy. 111 FOREST PRACTICES INFLUENCING WATER AND THE HYDROLOGICAL REGIME OF THE FOREST Forest practices affect the forest’s hydrological re- The allowable annual cut (AAC), the rate at which gime in three main ways (see Chapter 6, “Hydrologic timber is made available for harvesting, is deter- Processes and Watershed Response,” and Chapter mined for each provincial management unit, which 7, “The Effects of Forest Disturbance on Hydrologic includes 37 Timber Supply Areas (TSAs) and 34 Tree Processes and Watershed Response”). Farm Licences (TFLs). The actual cut calculation is based on analyses of timber supply and the availabil- • Forest cover removal: logging (patterns of log- ity of timber over time, and is influenced by many ging), natural disturbances (fire, insects, diseases, social, economic, and environmental considerations. windthrow, landslides / earth movements), fire Some of the factors considered include: inventory prevention and suppression information on the actual amount of land available; • Regenerating the forest: natural regeneration, reductions in the timber land base owing to the artificial regeneration through planting creation of new parks or the building of transmis- • Transporting wood: movement of wood to mills sion lines; the many types of forest stands and their and timber products to markets via water, rail, volume and growth rates; the depletion of timber by and road agents such as fire, insects, and diseases; the timber utilization level (or the amount of a tree that can be Forest Cover Removal used); and the accessibility of timber using current technology. The AAC has risen from approximately Forest cover influences a number of important 15 million m3 in the mid-1960s to its current level of hydrologic processes, including interception of approximately 60 million m3. The most recent AAC precipitation, snow accumulation and melt, and rose to a temporary level of approximately 75 million evapotranspiration (see Chapter 6, “Hydrologic m3 because of the mountain pine beetle infestation. Processes and Watershed Response”). Both natural The actual amount of timber cut depends on and human-caused disturbances can remove forest market conditions. The individual licensees have cover, affecting hydrologic processes. Natural dis- some flexibility over the amount actually cut in any turbances include wind, landslides, insects, diseases, given year within their periodic cut control licence and wildfire. Human activity can initiate or modify agreement (usually 5 years). This flexibility accounts all of these natural disturbances, and cause direct for the discrepancy between published allowable cut disturbance through activities such as logging, road and actual cut figures. building, and settlement construction. Hydrologic The timber supply of each management unit is processes can influence and be influenced by all of reviewed at 5-year intervals, with more frequent re- these disturbances to varying degrees. For example, views following large-scale disturbances such as ma- excess soil moisture can intensify the effects of wind, jor wildfire events or large-scale pest outbreaks (e.g., leading to increased windthrow and (or) contribute mountain pine beetle infestation). In each review, to landslides; insect and disease activities are fre- the data and assumptions used to determine the AAC quently associated with either an excess or shortage are made available to the public for comment before of precipitation and soil moisture; and fires often a final decision is made. start during droughts and in certain situations may Once the level of cut is determined for a given only be extinguished by prolonged precipitation. management unit, the way in which forest cover is Forest cover removal by logging is controlled removed is determined by the choice of silvicultural through the amount of timber cut within a manage- system (Figure 5.1). A silvicultural system is defined ment unit and through the method of harvesting. as a systematic program of silvicultural treatments The amount of timber volume harvested on Crown over the life of a stand. Clearcutting is the best- land in the Provincial Forest and Tree Farm Licences known example. It involves removal of the entire is determined by the Chief Forester, and controlled forest stand in one operation with regeneration of by limits placed on individual licensees under Sec- the forest obtained artificially or from seeds ger- tion 8 of the Forest Act and through subsequent minating after the harvest. Until relatively recently, legislation, standards, and guidebooks that govern almost all harvesting in British Columbia followed forest practices and planning. the clearcutting system. In the early 1900s, all forest 112 Clearcut Soon after harvest 5–7 years 15–20 years after harvest after harvest Seed Tree Grouped seed tree system Uniform seed tree system Variable Retention Group Selection FIGURE 5.1 Schematics of various silvicultural systems. (Adapted from B.C. Ministry of Forests and Range 1999) cover was removed from thousands of hectares of watersheds at any one time. Complex rules now land over relatively short periods of time with no govern the extent of clearcutting within a water- deliberate regeneration efforts. The effects of this shed to limit these effects. Much recent hydrological “continuous” clearcutting on hydrologic processes research has focussed on developing more effective was dramatic and, together with the poor aesthetics and less costly restraints on logging operations. of hillsides laid bare from horizon to horizon, led to Silvicultural systems other than clearcutting large-scale public protests and eventually limits on can be employed (Figure 5.1). Currently, the most the amount of cover that could be removed within common is clearcut with reserves, with the reserves 113 covering 10% of the clearcut area. This is a minor Regenerating Forest Cover modification of the clearcutting system that leaves some structural heterogeneity in varying amounts, Some form of natural regeneration occurs on almost types, and spatial patterns of living and dead trees all forest lands in British Columbia (Figure 5.2). to address a broad array of forest management goals. Natural ingress of lodgepole pine in the Interior The retention of later seral conditions is assumed to is abundant and western hemlock on the Coast sustain ecosystem functions and biological diversity regenerates rapidly, even in large openings. Over at the stand level. Variable retention is designed to the past 40 years, however, various land cultivation increase the amount of cover left on the logged area and plant propagation techniques were developed and the amount can range from 30 to 70% across the and applied to speed up regeneration and improve cutblock. Seed tree and shelterwood systems are used the quality of regeneration for future harvesting. to increase natural regeneration on the cutblock. The Some form of site preparation followed by planting is retained cover can vary from 5 to 50%.