Timber Harvest Trafficking and Soil Compaction in Western Montana

Abstract

Little evidence is documented regarding the effects of timber‐harvest traffic on volcanic‐ash‐mantled glacial till soils and clay‐rich Tertiary volcanic‐derived soils of northwestern Montana. We identified and characterized differences in the soil physical properties between trafficked and nontrafficked areas. Soil‐clod bulk density, infiltration, and soil‐clod water retention were measured on 54 pedons from nontrafficked and moderately and severely trafficked sites. Soil mechanical properties were characterized using 18 nontrafficked pedons. Compared with nontrafficked areas, bulk densities in severely trafficked areas at the 15‐cm depth were 76, 21, and 21% greater in ash over limestone till, ash over quartzite till, and Tertiary volcanic soils, respectively. Water retention at 0.002, 0.010, and 0.033 MPa was significantly lower at the 15‐cm depth in trafficked than in nontrafficked areas of ash over limestone till. Similar differences were observed in ash over quartzite till. Compared with nontrafficked areas, cumulative 1‐h infiltration in severely trafficked areas was 81% less in ash over limestone till, 79% less in ash over quartzite till, and 87% less in Tertiary volcanic soils. Similar but smaller differences were detected in moderately trafficked areas. Three independent measurements demonstrated significant differences in surface horizon physical properties between trafficked and nontrafficked areas. We detected significant physical manifestations of traffic‐induced soil compaction below 30 cm.

Effects of tree-length timber skidding on soil compaction in the skid trail in Hyrcanian forests

“…However, Gayoso and Iroume (1991) stated that this may be a consequence of the problems that the skidder might face when logging in steep terrains. In this study there was not only compaction at all three depths but with increasing soil depth the compaction level also increased, which is in agreement with the results of other researchers (Cullen, 1991;Horn et al, 2004;Eliasson, 2005;Bolding et al, 2009;Ampoorter et al, 2010). This is related to the rather homogeneous weight distribution of the skidder on the flat skid trails.…”

“…Forest soils, in general, are susceptible to compaction as they are loose with high organic-matter, are generally low in bulk density, high in porosity, and low in strength (Froehlich et al, 1985;Kolkaa and Smidt, 2004;Horn et al, 2004). The impact of skidding operations on forest soils can be divided into three major categories: soil prof ile disturbance, soil compaction and soil puddling and rutting (Cullen, 1991;Rab, 1996).…”

Mechanical disturbance impacts on soil properties and lodgepole pine growth in British Columbia’s central interior

“…Bulk density is slow to change (i.e., recover from mechanical disturbance) and is a widely used property for measuring forest soil compaction (Froehlich et al 1986;Cullen et al 1991;McNabb et al 2001). This static property, however, may not completely describe how soil responds to compaction or its effect on plant growth.…”

Effects of soil compaction on growth and survival of tree saplings: A meta-analysis

“…However, these machines may seriously influence the soil ecosystem as they induce rutting, churning of the upper soil layers, and soil compaction. The latter implies a decrease of soil pore continuity (Benthaus & Matthies, 1993), compression of soil pores, and an increasing soil bulk density (Cullen, Montagne & Ferguson, 1991). Aust, Burger, Carter, Preston & Patterson (1998) stated an increased penetration resistance after machine traffic, a measure for the resistance that a soil exerts against root growth.…”