The use of strip-seeding for management of two late-season invasive plants

Abstract

The spread and persistence of weedy plants in rangelands highlight the need for refinement of existing management techniques and development of novel strategies to address invasions. Strip-seeding – the strategic seeding of a portion of an invaded area to reduce costs and enhance success – is an underutilized management approach that holds promise for reducing weed dominance in grassland habitats. A strip-seeding experiment was established in 2011 in a California grassland where portions (between 0-100%) of invaded plots were seeded with native grasses. In 2016, we assessed the height, above-ground biomass and flower production of two late-season invasive plants: field bindweed and prickly lettuce. We found significant reductions in plant height and flower production (for both target invasives), and biomass (for field bindweed) in many of the seeded strips compared to the unseeded strips. Smaller seed applications demonstrated similar or better utility for weed control compared to greater seed applications, suggesting that this approach can be effective while reducing labor and materials cost of typical restoration management approaches. We did not find evidence that seeded strips provided invasion resistance to unseeded strips. This is possibly due to the lag in native species dispersal and establishment into contiguous unseeded strips, and suggests that strip-seeding might not provide invasion resistance to unseeded strips on timescales that are relevant to managers. However, this work does suggest that strip-seeding native species that overlap in phenology with target invasives can reduce late-season weed dominance on rangelands.

The use of spatially patterned methods for vegetation restoration and management across systems

“…The proposed benefits of spatially patternedrestoration methods include reducing management costs and increasing implementation feasibility over large areas (Corbin & Holl 2012;Rayburn & Laca 2013;Hulvey et al 2017). Potential ecological benefits include establishment of native plants in highly invaded areas (Bradley 1997) through the reduction of invasive dominance (Dechen Silva et al 2019) and increasing structural heterogeneity to better simulate natural ecosystem structure (Holl et al 2011;Gornish et al 2019) by mimicking natural successional processes (Corbin & Holl 2012). However, these methods can take longer than traditional active restoration methods to achieve the same outcomes, particularly in terms of plant or canopy cover (Jongepierová et al 2007;Holl et al 2011).…”

Using strip seeding to test how restoration design affects randomness of community assembly

“…Priority effects can drive successional processes (Connell & Slatyer )—a slow, nonrandom development to a particular community—through the inhibition of later arrivals. Clearly, a strip seeding approach can create differences in community assembly in restored areas through a variety of mechanisms (Young et al ; Dechen Silva et al ). Because community assembly can be driven by processes that affect other management priorities (such as productivity, e.g.…”

Seed use in the field: delivering seeds for restoration success

“…Overseeding, interseeding, and gap seeding involve the addition of seeds to enhance an existing natural community or seeding. These operations can be conducted to increase species diversity, alter community structure across a site, or restore depleted or weed‐infested areas (Rayburn & Laca 2013; Silva et al 2019). Diversification of species‐poor native vegetation or seedings is often hampered by microsite limitations (Münzbergová & Herben 2005); disturbance to reduce competition or improve microsite availability is often necessary before species introduction occurs (Schmiede et al 2012; Baasch et al 2016; Kiss et al 2020).…”