Understanding the natural patterns of regeneration following human disturbance is essential for effective restoration and management of second-growth forests. Despite their unique ecological character, little is known about these patterns in Sequoia scnipervirens (D. Don) Endl. (Coast Redwood) forests. We examined the composition and structure of naturally regenerating stands with 360 randomly located sample plots across a chronosequence of five replicated age-classes ( 18 to 127 yr) and three old-growth reference sites. Results indicate a progression of stand characteristics towards old-growth conditions, with several measures reaching old-growth equivalence within the timeframe of the chronosequence. Stand density, canopy cover, and species richness reached old-growth equivalence within 41-80 yr; Shannon-diversity reached old-growth equivalence between 80-100 yr; and the density of redwood seedlings and shrub cover reached old-growth equivalence between 100-130 yr. Basal area, herb cover, and the relative dominance of S. sempervirens progressed toward, but did not reach, old-growth equivalence. Size-class analysis indicated an increase in the density of large diameter trees, with no change in the density of smaller size-classes after forty yr. Coast redwood associated understory species were favored on the older sites with the cover of Calypso bulbosa (L.) Oakes, Trillium ovatum Pursh, and Viola sempervirens Greene reaching old-growth equivalence, while Iris douglasiana Herb., Tiarella trifoliate L., and Aelilys triphylla (Sm.) DC. did not. No non-native species were recorded in stands older than 60 yr. We conclude that coast redwood forests are resilient to human disturbance, though some old-growth characteristics may require more than a century to develop.

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Fire plays a central role in determining structure, composition, and recruitment in many forest types. In coast redwood forests, the role of fire is not well understood and scant literature exists on postfire response, particularly in the southern part of the range. In order to better understand patterns of survival and recruitment following fire for coast redwood (Sequoia sempervirens [lamb. ex D. Don] Endl.) and associated tree species, three sites in the Santa Cruz Mountains, California, USA, were sampled following wildfire. Randomly selected 10 m diameter plots were used to collect data on survivorship and post fire regeneration in order to analyze shortterm responses including mortality, crown retention, basal sprouting, canopy regeneration, and seedling production. Results indicated that coast redwood had the lowest percent mortality (11.98 %) and highest mean canopy retention (43.10 %) of all species sampled, followed by Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) (25.54 %), tanoak (Notholithocarpus densiflorus [Hook. & Arn.] Manos) (23.27 %), combined oak species (Quercus sp.) (6.67 %), and Pacific madrone (Arbutus menziesii Pursh) (4.13 %). In addition, associated species experienced higher survival rates when proximate to coast RESUMENEl fuego desempeña un papel central en la determinación de la estructura, composición y reclutamiento en diversos tipos de bosque. En los bosques costeros de secoyas, el papel del fuego no se entiende bien y existe escasa literatura sobre las respuestas post-incendios, particularmente en la parte sur de la cordillera. Para entender mejor los patrones de sobrevivencia y reclutamiento de la secoya costera (Sequoia sempervirens [lamb. ex D. Don] Endl.) y especies arbóreas asociadas después del fuego, se muestrearon tres sitios en las Montañas de Santa Cruz, California, EUA después de un incendio. Se establecieron parcelas de 10 m de diámetro, seleccionadas aleatoriamente, para colectar datos de sobrevivencia y regeneración post-incendio con el fin de analizar las respuestas a corto plazo incluyendo mortalidad, retención de copa, rebrotes basales, regeneración de dosel y producción de plántulas. Los resultados indicaron que la secoya costera presentó el porcentaje más bajo de mortalidad (11.98 %) y la más alta retención de copa (43.10 %) de todas las especies muestreadas, seguida por el abeto Douglas (Pseudotsuga menziesii [Mirb.] Franco) (25.54 %), tanoak (Notholithocarpus densiflorus [Hook. & Arn.] Manos) (23.27 %), encinos (Quercus sp.) (6.67 %) y madroño del Pacífico (Arbutus menziesii Pursh) (4.13 %). Además, las especies asociadas experimentaron tasas de sobrevivencia más altas cuando estaban cercanas a las secoyas. Los árboles Fire Ecology Volume 10, Issue 1, 2014 doi: 10.4996/fireecology.1001043 Lazzeri-Aerts and Russell: Survival and Regeneration Following Wildfire Page 44 redwoods. Coast redwood trees also exhibited the highest canopy regeneration (53 %), the highest average density of basal sprouts (3.54 × 10 4 ha), and the greatest average nu...

The management of second-growth Sequoia sempervirens (coast redwood) forests for the purpose of restoration and ecological conservation is a growing trend. However, little is known about the long-term regenerative potential of this forest type in the absence of post-harvest management techniques such as thinning and planting. Data on forest composition and structure were collected on a chronosequence (80-160 years) of mature recovering stands in the southern coast redwood range using a replicated, randomized, plot design. Results indicated that many stand characteristics including tree density, canopy cover, redwood dominance, species richness, herbaceous cover, and shrub cover reached levels statistically equivalent with old-growth reference sites in recovering stands within the time frame of this chronosequence. The recovery of individual herbaceous understory species was inconsistent however. While the cover of redwood-associated species (Oxalis oregana, Trientalis latifolia, and Disporum hookeri) reached levels statistically equivalent to old-growth reference sites, others (Trillium ovatum and Viola sempervirens) did not. Total basal area and species evenness also trended toward, but did not reach, old-growth conditions. The arboreal aspects of coast redwood forests appear to be remarkably resilient following a single logging event, and recover rapidly in the absence of active restoration techniques. The protracted recovery of certain redwood associated herbaceous understory species will require further study.