We asked whether prescribed fire could be a useful management tool to reduce invasion by non-native plants in an ecosystem where native plants are supposed to be adapted to fires. Specifically, we compare the post-fire resprouting response of native and non-native woody species in Chaco Serrano forest of central Argentina. The measurements were carried out in five burnt areas where we selected ten native and seven non-native species. Our response variables were (1) post-fire survival, (2) types of resprouts, and (3) the growth of the resprouts. Our main results show that one year after the fire, survivals of native and non-native species were 0.84 and 0.89, respectively, with variances in survival seven times smaller in the native species group. Type of resprout was also less variable in native species, while growth of the resprouts was similar in native and non-native groups. We interpret that in most cases, the burning a forest with mixed native and non-native plants through prescribed fires will not differentially stop the invasion by non-native woody species even in ecosystems which are presumed to be relatively resistant to fires such as our study area.

Domestic livestock are widespread in seasonally dry forests, likely causing forest degradation and limiting tree seedling establishment. Shrubs can play an important role in facilitating tree regeneration, by protecting trees from livestock damage and ameliorating unfavorable abiotic conditions. We aimed at disentangling the relative contribution of grazing exclusion, long‐term forest conservation, and the potential facilitation effect of shrubs on the performance of saplings of the native tree Kageneckia lanceolata. We planted 400 saplings in grazed and ungrazed areas situated both in a preserved and a degraded forest. In each situation, we established planting plots in three accompanying vegetation treatments: herbs, a nonleguminous spiny shrub and a leguminous spiny shrub. Survival of 3‐year‐old saplings was 10‐fold higher in the preserved than in the degraded forest and 2‐fold higher in the ungrazed than in the grazed site. Differences in survival among accompanying vegetation treatments were much smaller than between grazing treatments. Survival significantly increased with increasing protection by shrubs only in the degraded site. Sapling growth patterns were fairly similar to survival patterns, with no growth in the degraded forest, except for limited growth under both shrubs in the ungrazed site. We conclude that, in selecting plantation sites for the study species, forest condition and grazing exclusion should be prioritized over microsite selection based on neighboring vegetation.

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HIGHLIGHTS Kageneckia lanceolata is a vulnerable Neotropical tree distributed in mountain areas. Seedling survival increased with elevation of the parent tree from 40 to 80%. Damping-off was the only identified cause of seedling mortality under nursery conditions. Seed mass, germination, and growth of seedlings were not influenced by elevation.

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En sistemas con lluvias estacionales, el rendimiento hídrico (caudal de salida del curso de agua relativo al área de la cuenca) en la estación seca depende de las lluvias previas y de la infiltración y la evapotranspiración, procesos que, a su vez, están afectados por las características del paisaje. Nuestro objetivo fue evaluar el efecto de distintas variables de paisaje sobre el rendimiento hídrico y la tasa de recesión (tasa a la que disminuye el caudal) durante la estación seca, en cuencas de alta montaña del centro de la Argentina. Seleccionamos 33 cuencas de 9-61 ha, y durante el final de la estación seca de 2017 medimos semanalmente el caudal en sus puntos de cierre durante siete semanas consecutivas. Para cada cuenca calculamos el rendimiento hídrico (mm/mes) promedio y un índice de recesión (adimensional) como la diferencia normalizada del rendimiento entre las últimas y las primeras fechas. Los paisajes extensamente ocupados por un mosaico de pajonal y roca, con pendiente y rugosidad intermedias, tuvieron los rendimientos hídricos máximos (>5 mm/mes). Por lo contrario, el rendimiento hídrico fue más bajo tanto en los paisajes suaves y cubiertos por vegetación, como en los muy ásperos (muy rugosos, escarpados y rocosos). Por su parte, la recesión fue lenta en los paisajes más ásperos y muy abrupta en los paisajes más suaves. Posiblemente, en los paisajes suaves y vegetados se pierde mucha agua por evapotranspiración, mientras que en los paisajes muy ásperos se pierde mucha agua por escorrentía después de las lluvias. Los paisajes con aspereza intermedia y un mosaico de vegetación y roca serían los que optimizan el almacenamiento, minimizando las pérdidas por evapotranspiración. Por lo tanto, para sostener el rendimiento hídrico es prioritario conservar este tipo de paisajes, evitando la erosión del suelo que genera un aumento de áreas rocosas.

Forest restoration is a great challenge when saplings are repeatedly pruned by leaf-cutting ants and pesticides are not permitted. Based on four hypotheses (distance-dependent foraging, plant repellence, structural complexity, and nutrient content), we predicted that sapling performance increases and ant pruning decreases: (1) away from leaf-cutting ant nests; (2) in unpalatable or (3) tall vegetation patches; and (4) in non-fertilized soils. We set up a full factorial field experiment to test the hypotheses; we also monitored sapling performance without and with plastic tree shelters used by practitioners to deter ant pruning. Our results showed predicted sapling survival from 40 to 80% per year for distances to nests ranging from 4 to 223 m, respectively. Ant pruning decreased with increasing distance, with null pruning at distances >121 m. Variation in sapling survival, but not in ant pruning, was also explained by the interaction between vegetation palatability and nutrient condition. Vegetation height did not explain sapling survival or pruning. Plastic tree shelters increased survival by 3.5 times and reduced pruning by half. Height of surviving saplings was not affected by any treatment. Our results show the potential for active forest restoration without the use of tree shelters away from leaf-cutting ant nests, while tree shelters are a viable option near leaf-cutting ant nests.