Timothy Paysen

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Efectos del fuego prescrito bajo arbolado de P.Pinaster en suelos forestales de Galicia y Andalucía

Cuadernos de la Sociedad Española de Ciencias Forestales, Jun 1, 2000

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Poster Session-Extended Abstracts

Notes, 2008

Author: Alexander III, Jack D.; Findley, Jean; Kury, Brenda K.; Beyers, Jan L.; Cram, Douglas S.;... more

for Use in California: Its Conceptual Basis

TIMOTHY E. PAYSEN, a research forester, is assigned to the Station's chaparral and related e... more

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Experiment Station A Vegetation Classification System Applied to Southern

development program at this Station titled "Vegetation Management Alternatives for

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Vegetation Classification—california 1 2

Research Forester, Pacific Southwest Forest and Range Experiment Station, Forest Service, U.S. De... more Research Forester, Pacific Southwest Forest and Range Experiment Station, Forest Service, U.S. Department of Agriculture, Riverside, Calif. Abstract: Vegetation classification in California is evolving rapidly. Broad-brush classes generated by resource management functions and ecologists are not suitable for many current needs. A new California system for vegetation classification fills many current needs for communication between disciplines and for linking existing classification systems.

format_quoteThe system is a neutral, component-based classification focusing solely on vegetation, applicable to various vegetation types.format_quote

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Trunk and Root Sprouting on Residual Trees After Thinning a Quercus chrysolepis Stand

Forest Science, 1991

Canyon live oak (Quercus chrysolepis Liebm.) showed sprouting patterns on root and trunk zones fo... more Canyon live oak (Quercus chrysolepis Liebm.) showed sprouting patterns on root and trunk zones following forest thinning. Root sprouting was heaviest on north and east (downhill) sides of residual trees; bole sprouts were concentrated on the south and west (uphill). Root and bole sprouting appeared to be responding to different stimuli, or respending differently to the same kind of stimulus. Thinning affected sprout growth, but not sprout numbers. Sprouting responses were at the tree level rather than the thinning treatment level. Unexpected sprouting occurred in uncut control plots. Light, tempera- ture, or mechanical activity may have affected sprouting on trees in the thinned plots. A better understanding of factors affecting sprout physiology in this species is required in order to fully explain sprouting responses following stand thinning. FOR. SCl. 37(1):

format_quoteSprouting occurred in all plots, including controls, with no consistent relationship observed between control and treatment plots.format_quote

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Quemas prescritas en el suroeste y en la costa pacífica suroccidental de los Estados Unidos

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Vegetation classification system for California: user's guide

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A system of vegetation classification applied to Hawaii

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Chamise Chaparral Dead Fuel Fraction Is Not Reliably Predicted by Age

Western Journal of Applied Forestry, 1990

Fire managers of southern California chaparral often assume that the amount of dead material in c... more Fire managers of southern California chaparral often assume that the amount of dead material in chaparral shrubs is closely related to canopy age. Analysis of chamise (Adenostoma fasciculatum), sampled from southern California shrublands, indicates that the ratio of dead to live components is not related reliably to age of shrub canopy. Further statistical description of the data indicates that fractions of dead material greater than 0.40 are rare. The results provide grounds for seriously questioning current assumptions about the strong relationship between age and fraction dead in southern California chaparral fuels. West J. Appl. For. 5(4):00-00, October 1990.

format_quoteDead material in chaparral shrubs is unrelated to canopy age, challenging common fire management assumptions.format_quote

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A vegetation classification system applied to southern California

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A vegetation classification system for use in California: its conceptual basis

We thank Ivan E. Parker of the Pacific Southwest Region's Land Management Planning Staff, Forest ... more We thank Ivan E. Parker of the Pacific Southwest Region's Land Management Planning Staff, Forest Service, U.S. Department of Agriculture, for his active participation in developing earlier manuscript drafts and for his pungent critique of concepts and philosophies that would have earned for him the right to coauthorship had time and priorities allowed him to become involved in developing the final draft. Responsibility for final content, concepts, and philosophies rests with us. We also thank members of the California Interagency Vegetation Task Group who provided technical review of this paper:

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Burning Irrigated and Unirrigated Chamise 1

ABSTRACT

Age-Class Mosaics and Wind-Driven Fire: Further Fuel for the Debate

In 2006 the Santa Ana wind-driven Esperanza fire burned through the North Mountain Experimental A... more In 2006 the Santa Ana wind-driven Esperanza fire burned through the North Mountain Experimental Area (NMEA) and vicinity, including the scars of 10 previous fires. Multiple images of the fire's progression were taken using PSW Research Station's airborne FireMapper thermal-imaging system. Existing fuels data and historic NMEA maps plus new fire images were used to investigate relationships between vegetation history, fire behavior and severity, and fuel consumption. Soil samples were collected at a subset of fire severity sample points to assess seed bank survival. Coordinated documentation of vegetation recovery addressed the effects of age class and fire severity on chaparral regeneration and non-native species invasion. Ground sampling of fuel characteristics combined with remote sensing demonstrated that the multispectral FireMapper instrument can provide an improved means to acquire the needed pre and post-fire fuels data necessary for quantitative, high-resolution measurement of wildland fire. Detailed analysis of the field data and remotely sensed data showed that the standard fire behavior fuel models for chaparral and grass did not capture the range of fuel loading associated with elevation and stand age. Fuel loading showed a general correspondence with observed fire behavior (radiant heat release (W m-2). Southwestern spread of the Esperanza Fire was contained near boundaries of previous fires and young fuels. Fuel, fire perimeter, and energy release data from FireMapper roughly agreed with simulation results from the CAWFE model. We were able to use FireMapper imagery to identify and differentiate various landscape features on vegetation plots to transect resolution. This included separation of general plant characteristics such as large compared to small leafed species. Sequential images reflected the increased plant cover observed from repeated measurements of vegetation plots. This technology appears to have utility for monitoring general plant cover recovery for large and/or remote areas. Areas containing older chaparral stands (>50 years since last fire at the time of the Esperanza fire) and higher fuel loading corresponded to areas of higher burn severity (as determined by ground crews). Species richness was greatest in mid-age burns (11-50 years since previous fire). At three years postfire, non-native grasses were the most abundant cover type. Non-native species dominated both burned and unburned fuel breaks.

format_quoteFireMapper imagery confirmed fire behavior patterns and enabled fine-scale differentiation of vegetation types, supporting improved fire management strategies.format_quote

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Burning California Chaparral - an Exploratory Study of Some Common Shrubs and Their Combustion Characteristics

International Journal of Wildland Fire, 1991

Prescribed fire is a tool used to manage vegetation in southern California. The nature and quan t... more Prescribed fire is a tool used to manage vegetation in southern California. The nature and quan tity of gaseous and particulate emissions have not been described for California chaparral. A study examining carbon monoxide (CO), carbon dioxide (CO2), and par ticulate matter emissions from fuel beds constructed from common chaparral shrubs was initiated. Chamise (Adenostoma fasciculatum), ceanothus (Ceanothus crassifolius), manzanita (Arctostaphylos glandulosa), and scrub oak (Quercus dumosa) fuel beds were burned in December 1989, and March, May, and August, 1990. Gas and particulate matter samples were collected from 45 fires. Emission factors for CO2 and particulate matter were affected by species and month individually; month and species interacted and affected CO emission factors.…

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The science of prescribed fire: to enable a different of control

Fire in ecosystem management: …, 1998

A paradigm shift from fire suppression to fire suppression and prescription requires a shift in e... more A paradigm shift from fire suppression to fire suppression and prescription requires a shift in emphasis from simply controlling wildfire occurrence and spread to one that includes controlling characteristics of prescribed fire. Suppression focuses on preventing unwanted effects that might result from wildfire occurrence. Prescription promotes desired effects by precisely and properly implementing fire occurrence. The duality of these concepts requires a new research focus. Research must now determine how to control processes that constitute a specific fire event. Each fire event includes specific of fire behavior and simultaneously activated ecosystem processes. Control of a fire event, to the degree needed to reach specific prescribed fire objectives, is complicated. It requires an understanding of many aspects of fire behavior and the complex processes that might be activated by the fire. It also requires knowledge of preconditioning factors that control both the nature of fire behavior and the response of a site to a particular fire event. Needed research is both multidisciplinary and interdisciplinary. It requires contributions from a wide range of backgrounds, including plant physiology, ecology, fire physics, and others. This new research focus will promote a broad array of investigations which address various levels of detail, and will advance the science of prescribed fire.

format_quoteA prescribed fire manager must understand fire behavior and environmental conditions to achieve specified goals during a fire event.format_quote

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Efectos del fuego prescrito bajo arbolado de P. pinaster en suelos forestales …

Actas Taller sobre …

Page 1. Cuadernos de la SECR, NO 9,junio 2000, pp. 123-136 «1 Retmión Grupo de Incendios Forestal... more

Tree mortality 6 years after burning a thinned Quercus chrysolepis stand

Canadian Journal of Forest Research, 1993

2236 Tree mortality 6 years after burning a thinned Querem chrysolepis stand1 Timothy E. Paysen a... more

Indications of vigor loss after fire in Caribbean pine (Pinus caribaea) from electrical resistance measurements

International Journal of …, 2006

... This adds credence to Taylor's assertion that the entire savanna region burns each year,... more ... This adds credence to Taylor's assertion that the entire savanna region burns each year, with 'only accidental exceptions' (Taylor 1959). The chance of frequent reburns is high for a given stand. ... Based on local experience, this pine is thought to have a good chance of survival. ...

Prescribed Fire Site Characteristic Effects on Soil and Cambium Temperatures

Timothy Paysen

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