Life Stage and Neighborhood-Dependent Survival of Longleaf Pine after Prescribed Fire

Determining mechanisms of plant establishment in ecological communities can be particularly difficult in disturbance-dominated ecosystems. Longleaf pine (Pinus palustris Mill.) and its associated plant community exemplify systems that evolved with disturbances, where frequent, widespread fires alter the population dynamics of longleaf pine within distinct life stages. We identified the primary biotic and environmental conditions that influence the survival of longleaf pine in this disturbance-dominated ecosystem. We combined data from recruitment surveys, tree censuses, dense lidar point clouds, and a forest-wide prescribed fire to examine the response of longleaf pine individuals to fire and biotic neighborhoods. We found that fire temperatures increased with increasing longleaf pine neighborhood basal area and decreased with higher oak densities. There was considerable variation in longleaf pine survival across life stages, with lowest survival probabilities occurring during the bolt stage and not in the earlier, more fire-resistant grass stage. Survival of grass-stage, bolt-stage, and sapling longleaf pines was negatively associated with basal area of neighboring longleaf pine and positively related to neighboring heterospecific tree density, primarily oaks (Quercus spp.). Our findings highlight the vulnerability of longleaf pine across life stages, which suggests optimal fire management strategies for controlling longleaf pine density, and—more broadly—emphasize the importance of fire in mediating species interactions.

Assessment of natural regeneration of longleaf pine (Pinus palustris) 15 years post-regeneration control

We assessed natural regeneration of longleaf pine (Pinus palustris Mill.) using the data col-lected from the Escambia Experimental Forest in southern Alabama. Fifteen years following the regeneration control, natural regeneration of longleaf remained patchy across a wide range of site/stand conditions, with slightly more than half of all plots containing regeneration, but the den-sity of seedlings and saplings varied significantly. The abundance of seedlings ≤ 1-year-old was positively related to stand age and time since last fire, but negatively related to overstory basal area. The abundance of seedlings and saplings was positively related to stand age, but negatively related to time since last fire and overstory basal area. The probability of achieving ≥ 15,000 seedlings > 1-year-old but ≤ 1-m-tall ha-1 and ≥ 1,250 saplings > 1-m-tall ha-1 was, respectively, positively related to the ratio of time since last fire to overstory basal area and the ratio of quadratic mean diameter to site index. A longer fire interval (> two to three years) should be adopted to naturally regenerate longleaf. We did not find clear zones of exclusion present in natural regeneration even though over-story trees, seedlings and saplings tended to be repulsive spatially and > 80% grass stage seedlings and saplings occurred outside tree crowns.

Hysterical Amateurs: Wild Seeds Burning on the Grass Stage

Wild Seeds 2019.07 by Grass Stage, one of the most important theatre collectives in China, addresses the concerns of the working class and youth, and the power the patriarchy wields over both. The work of Grass Stage not only criticizes the capitalist and neoliberal economy of contemporary China but also rebels against the dominant socialist and communist ideological dogma.

Fire Survival of Longleaf Pine (Pinus palustris) Grass Stage Seedlings: The Role of Seedling Size, Root Collar Position, and Resprouting

Longleaf pine (Pinus palustris Mill.) forest is a well-known fire-dependent ecosystem. The historical dominance of longleaf pine in the southeast United States has been attributed to its adaptation known as the grass stage, which allows longleaf pine seedlings to survive under a frequent surface fire regime. However, factors affecting post-fire survival of grass stage seedlings are not well understood. In this study, we measured live and dead longleaf pine grass stage seedlings to quantify the role of seedling size, root collar position, and sprouting in seedling survival following a wildfire in the sandhills of South Carolina. We found that fire resulted in almost 50% mortality for longleaf pine grass stage seedlings. Fire survival rate increased with seedling size, but a size threshold for fire tolerance was not supported. Fire survival depended on the position of root collar relative to the mineral soil. Seedlings with protected root collars (i.e., buried in or at the level of mineral soil) experienced <21%, while seedlings with exposed root collars (i.e., elevated above mineral soil) suffered >90% post-fire mortality. Ability to resprout contributed to 45.6% of the total fire survival, with the small seedlings (root collar diameter (RCD) < 7.6 mm) almost exclusively depending on resprouting. Our findings had significant implications for fire management in longleaf pine ecosystems, and the current frequency of prescribed fire in sandhills might need to be lengthened to facilitate longleaf pine natural regeneration.

World Factory: Theatre, Labor, and China's “New Left”

In today's China, how are we supposed to understand the notion of “work,” after the chaos of the socialist period, and after the conversion to capitalism, and now after globalization? Marx said that labor makes people, this was one of his fundamental principles. So how are we supposed to understand labor today? What does it mean for us?—Grass Stage,World FactoryThe insistence on “socialism with Chinese characteristics” often sounds quite vacuous, and yet it is a constant reminder of the Chinese resistance to dissolution into capitalism and the continued reaffirmation of one kind of socialist past in the search for another kind of socialist future.—Arif Dirlik, “Back to the Future”