Effect of mastication and other mechanical treatments on fuel structure in chaparral

摘要: Mechanical fuel treatments are a common pre-fire strategy for reducing wildfire hazard that alters structure by converting live canopy fuels to compacted layer of dead surface fuels. Current knowledge concerning their effectiveness, however, comes primarily from forest-dominated ecosystems. Our objectives were quantify and compare changes in shrub-dominated chaparral following crushing, mastication, re-mastication mastication-plus-burning treatments, assess treatment longevity. Results analysis variance (ANOVA) identified significant differences all components type, vegetation type time since treatment. Live woody height, cover mass positively correlated with treatment, whereas downed negatively correlated. Herbaceous fuels, conversely, not correlated, exhibited 5-fold increase across types comparison controls. Average recovery was 50% types. Differences between time-since-treatment years 1–8 ranged 32–65% positive correlations These results suggest effectiveness is short term due the rapid regrowth shrubs these systems compromised substantial herbaceous Consequences having full understanding serious leave concern widespread use on chaparral-dominated landscapes.