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Individual study: The role of disturbance severity and canopy closure on standing crop of understory plant species in ponderosa pine stands in northern Arizona, USA

Published source details

Sabo K.E., Sieg C.H., Hart S.C. & Bailey J.D. (2009) The role of disturbance severity and canopy closure on standing crop of understory plant species in ponderosa pine stands in northern Arizona, USA. Forest Ecology and Management, 257, 1656-1662


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Thin trees within forests: effects on understory plants Forest Conservation

A replicated, controlled study in 1988-2005 in temperate coniferous forest in Arizona, USA (Sabo et al. 2009) found no effect of thinning on  understory plant biomass. Above ground biomass (kg/ha) of native grasses (unthinned: 600; thinned: 1,100) and forbs (unthinned: 300; thinned: 250) was similar between treatments. No non-native grasses or forbs were found in control or thinned plots. Data were collected in 2005 in 10 plots (20 × 50 m) in each of three unthinned and four thinned (>30% of basal area removed between 1988 and 1995) forest units (20-80 ha).