Uprooted buffelgrass thatch reduces buffelgrass seedling establishment

Abstract

Buffelgrass (Pennisetum ciliare (L.) Link), a non-native perennial bunchgrass, invades ecologically intact areas of the Sonoran Desert. It competitively excludes native plants and increases fire frequency and intensity. Since the 1990s, whole buffelgrass plants have been manually uprooted and removed to control the invasion in southern Arizona. Uprooting plants results in bare, disturbed soil which promotes buffelgrass seed germination. This study examined whether leaving entire uprooted buffelgrass plants (thatch) on a field site reduces future buffelgrass establishment compared to removing uprooted plants from the site. A secondary goal was to determine whether light reduction and autoallelopathy were major factors in the negative effect of thatch on buffelgrass seedling density. Field plots with an average of 8,095 kg/ha thatch had 1.9 buffelgrass seedlings/m 2 which was significantly fewer than the 2.9 seedlings/m 2 in plots without thatch. Thatched portions of thatch plots (50% of their total area) had only 0.7 seedlings/m 2 . In the greenhouse, which reduced outdoor light intensity by 35.2%, buffelgrass seeds sown in bare soil resulted in significantly higher seedling density than beneath buffelgrass thatch. Potential autoallelopathic chemicals leached from partially decomposed buffelgrass thatch and leached thatch had an intermediate but not significant (p ¼ 0.09) effect on seedling numbers. Results suggest that leaving uprooted buffelgrass plants has the benefit of reducing seedling establishment in the area disturbed by uprooting. ARTICLE HISTORY

Pennisetum ciliare: a review of treatment efficacy, competitive traits, and restoration opportunities

“…Pennisetum ciliare treatment approaches tend to be site specific, are developed in situ, have poor long-term success, can enhance invasion (e.g., Jernigan et al 2016), and are often poorly communicated among entities. Therefore, there is a need for a systematic review on the outcomes of various P. ciliare treatment methods and land management techniques to understand best practices and opportunities.…”

Cochliotoxin, a Dihydropyranopyran-4,5-dione, and Its Analogues Produced by Cochliobolus australiensis Display Phytotoxic Activity against Buffelgrass (Cenchrus ciliaris)

“…1,2 However, during the last three decades, buffelgrass has spread into undisturbed natural areas, causing significant ecological damage. 3,4 It has become highly invasive in some parts of its introduced range, particularly in the Sonoran Desert of southern Arizona. 5−7 In fact, it has infested thousands of acres of public and private lands, including Saguaro National Park and the Coronado and Tonto National Forests, competing with the native vegetation for water, nutrients, and space.…”

“…Buffelgrass ( Pennisetum ciliare or Cenchrus ciliaris ) is a perennial bunchgrass native to Africa and southern Asia that is an important pasture grass in many semiarid regions of the world. , However, during the last three decades, buffelgrass has spread into undisturbed natural areas, causing significant ecological damage. , It has become highly invasive in some parts of its introduced range, particularly in the Sonoran Desert of southern Arizona. − In fact, it has infested thousands of acres of public and private lands, including Saguaro National Park and the Coronado and Tonto National Forests, competing with the native vegetation for water, nutrients, and space. , At present the only approaches available to deal with buffelgrass invasion into natural ecosystems are broad-spectrum herbicides and physical removal with hand tools.…”

Pyriculins A and B, two monosubstituted hex‐4‐ene‐2,3‐diols and other phytotoxic metabolites produced by Pyricularia grisea isolated from buffelgrass (Cenchrus ciliaris)

“…Its fast growth, resistance to heavy grazing, drought tolerance, and forage value promoted its exponential growth as an important pasture grass in many semiarid regions of the world, including Texas . Unfortunately, buffelgrass started to spread into undisturbed natural areas and since the 1980s it has become one of the most serious invaders in some parts of its introduced range . Particularly dramatic is the situation in the Sonoran Desert of southern Arizona, where it has infested thousands of acres of public and private lands, including Saguaro National Park and the Coronado and Tonto National Forests.…”