Radial Dispersion of Neighbors and the Small-Scale Competitive Impact of Two Annual Grasses on a Native Perennial Grass

The species composition of temperate grasslands in the mid-north of South Australia has been radically altered from a system dominated by native perennial grasses to a system dominated by Mediterranean annual grasses. This study investigated the importance of chemical and physical soil characteristics, topographical features and climatic variables on the abundance of native and exotic grass species in nine ungrazed grasslands. Overall, climatic and other abiotic factors were highly variable. In addition, past management practices and original species composition are generally unknown, leading to further unexplained variation in the data. On a large spatial scale (among sites), the abundance of exotic annual grasses was positively correlated with mean annual rainfall, and on any scale, with finer soil textures and higher soil organic carbon levels. The most abundant annual grass, Avena barbata (Pott ex Link), was generally associated with soil factors denoting higher soil fertility. The abundance of native perennial grass species was not correlated with any environmental variables at any scale. The various native perennial grass species did not show clear associations with soil factors, although they tended to be associated with factors denoting lower soil fertility. However, at small spatial scales (within some sites) and among sites, the abundances of exotic annual and native perennial grasses were strongly negatively correlated. The results suggest that at the present time, rainfall and soil properties are important variables determining the abundance of annual grasses. The driving variables for the abundance of perennial grasses are less clear. They may be controlled by other factors or extreme rainfall events, which were not surveyed. In addition, they are likely to be controlled by competitive interactions with the annual grasses.

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Coexistence and interference between a native perennial grass and non-native annual grasses in California

Oecologia ◽

10.1007/s004420050958 ◽

1999 ◽

Vol 121 (4) ◽

pp. 518-526 ◽

Cited By ~ 125

Author(s):

J. G. Hamilton ◽

Claus Holzapfel ◽

Bruce E. Mahall

Keyword(s):

Perennial Grass ◽

Annual Grasses ◽

Native Perennial Grass

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Invasive Grasses Increase Nitrogen Availability in California Grassland Soils

Invasive Plant Science and Management ◽

10.1614/ipsm-09-046.1 ◽

2010 ◽

Vol 3 (1) ◽

pp. 40-47 ◽

Cited By ~ 24

Author(s):

Sophie S. Parker ◽

Joshua P. Schimel

Keyword(s):

Nitrogen Availability ◽

Perennial Grass ◽

N Cycling ◽

Rooting Depth ◽

Grass Species ◽

Annual Grass ◽

Annual Grasses ◽

California Grassland ◽

Pool Sizes ◽

Native Perennial Grass

AbstractAs Europeans colonized California, they introduced annual grasses from the Mediterranean Basin. These exotic annual grasses eventually invaded grasslands throughout the state, some of which were once dominated by native perennial grass species. Annual grasses differ from perennials in their phenology, longevity, rooting depth, litter chemistry, and interaction with the microbial community. As these traits may influence plant nitrogen (N) use, it is likely that the invasion by annual species resulted in changes in the availability and cycling of N in California grassland systems. We addressed the question of how invasive annual grasses influence rates of N cycling by measuring N pool sizes and rates of net and gross mineralization and nitrification, gross immobilization, and the denitrification potential of soils from experimentally planted annual and perennial-dominated grasslands. With an increase in annual grass cover, we saw increases in ammonium (NH4+) pool sizes and rates of N mineralization, nitrification, and denitrification in soils. These differences in N status suggest that N cycling in California grasslands was altered at sites where native perennial bunchgrasses were invaded by nonnative annual grasses. One consequence of annual grass invasion may be a legacy of NH4+-enriched soils that hinder the reestablishment of native perennial grass species.

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Fitness components and the determinants of fecundity in populations of a native perennial grass ( Tridens flavus )

Plant Species Biology ◽

10.1111/1442-1984.12318 ◽

2021 ◽

Author(s):

Gregory P. Cheplick

Keyword(s):

Perennial Grass ◽

Fitness Components ◽

Native Perennial Grass

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Regeneration Technique of Bamboo Species through Nodal Segments: A Review

Nepal Journal of Biotechnology ◽

10.3126/njb.v8i1.30209 ◽

2020 ◽

Vol 8 (1) ◽

pp. 54-68

Author(s):

Meena Maiya Suwal ◽

Janardan Lamichhane ◽

Dhurva Prasad Gauchan

Keyword(s):

Large Scale ◽

Physiological Stress ◽

Perennial Grass ◽

Shoot Multiplication ◽

Nodal Segments ◽

Individual Species ◽

Small Scale ◽

Scale Production ◽

Bamboo Species

Micropropagation is an alternative technique to propagate at large scale plants to meet global plant demand. Various researchers have worked on the micropropagation technique to regenerate bamboo species by using nodal segments from years. Contamination, browning, necrosis, and acclimatization with physiological stress are the extreme problems of the micropropagation technique. But, many numbers of papers have been published on micropropagation of the bamboo species through nodal segments as explants. The proliferation of the bamboo shoots is dependent on the season of collection, size of explants, the position of explants, diversity of plants, concentration and combination of plant growth regulators, most adequate culture medium, environmental condition of the equipment, handling, and individual species. Bamboo is a monocarpic fast-growing, tall perennial grass and having the high potential to generate economic and social benefits. It helps to maintain land patterns and control soil erosion. The long life cycle of the bamboo produces a huge amount of seeds but unfortunately, mostly, they are non-viable. So, bamboos are propagated from vegetative by cutting and air layering. However, these methods are only for a small scale and they also tend to destroy large mother plant stocks and difficult to be transported. So, the in vitro propagation technique is useful to obtain large progenies from desired genotypes. Mostly, BAP and TDZ growth hormones are widely used for shoot multiplication and IBA, NAA and IAA are used for root initiation as per developed protocols in tissue culture for large scale production. This review intends to explore an overview of the recent literature reports to summarize the importance of micropropagation by using nodal segments of bamboo species and factors influencing it.

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Indirect effects of an invasive annual grass on seed fates of two native perennial grass species

Oecologia ◽

10.1007/s00442-013-2868-4 ◽

2014 ◽

Vol 174 (4) ◽

pp. 1401-1413 ◽

Cited By ~ 9

Author(s):

Susan E. Meyer ◽

Katherine T. Merrill ◽

Phil S. Allen ◽

Julie Beckstead ◽

Anna S. Norte

Keyword(s):

Indirect Effects ◽

Perennial Grass ◽

Grass Species ◽

Annual Grass ◽

Seed Fates ◽

Native Perennial Grass

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Control of Downy Brome (Bromus tectorum) with Herbicides and Perennial Grass Competition

Weed Technology ◽

10.1017/s0890037x00043980 ◽

1998 ◽

Vol 12 (2) ◽

pp. 391-396 ◽

Cited By ~ 40

Author(s):

Tom D. Whitson ◽

David W. Koch

Keyword(s):

Dry Matter ◽

Perennial Grass ◽

Integrated Approach ◽

Growth Stages ◽

Downy Brome ◽

Cool Season ◽

Growing Seasons ◽

Annual Grasses ◽

Russian Wildrye

Long-term control of downy brome with an integrated approach is needed in order to sustain range productivity. Studies were conducted to study the effectiveness of a combination of downy brome control practices. In two studies, glyphosate and paraquat were evaluated at various rates for up to three successive years for control of downy brome in rangeland. A third study evaluated the competitiveness of perennial cool-season grasses against downy brome in the absence of herbicides. Glyphosate, at 0.55 kg/ha, and 0.6 kg/ha paraquat provided selective downy brome control on rangeland when applications were combined with intensive grazing. Downy brome control was greater than 90% following two sequential years of 0.6 kg/ha paraquat at either the two- to eight-leaf stage or bloom stage at both study locations. At one study location, 0.55 kg/ha glyphosate provided 97% control after the first application at both growth stages. In the second study, control averaged greater than 92% following three sequential applications of glyphosate. When perennial cool-season grasses were seeded in the spring following fall tillage (no herbicides) and allowed to establish for three growing seasons, three of the five species were effective in reducing the reestablishment of downy brome. ‘Luna’ pubescent wheatgrass, ‘Hycrest’ crested wheatgrass, ‘Sodar’ streambank wheatgrass, ‘Bozoisky’ Russian wildrye, and ‘Critana’ thickspike wheatgrass controlled 100, 91, 85, 45, and 32% of the downy brome, respectively. Yields of perennial grass dry matter were 1,714, 1,596, 1,135, 900, and 792 kg/ha. Replacing noncompetitive annual grasses with competitive cool-season perennials will provide a longer term solution to a downy brome problem than the use of herbicides alone or with intensive grazing.

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Integrated Management of Perennial Pepperweed (Lepidium latifolium)

Invasive Plant Science and Management ◽

10.1614/ipsm-07-004.1 ◽

2008 ◽

Vol 1 (1) ◽

pp. 17-25 ◽

Cited By ~ 5

Author(s):

Rob G. Wilson ◽

Debra Boelk ◽

Guy B. Kyser ◽

Joseph M. DiTomaso

Keyword(s):

Integrated Management ◽

Perennial Grass ◽

Management Strategies ◽

Site Preparation ◽

Perennial Grasses ◽

Flower Bud ◽

No Till ◽

Wide Range ◽

Grass Establishment ◽

Native Perennial Grass

AbstractPerennial pepperweed is invasive throughout California. It thrives in a wide range of environments and is a common weed in floodplains, pastures, wetlands, and roadsides. In disturbed areas, perennial pepperweed rapidly forms monotypic stands with a thick litter layer. These infestations not only out-compete other vegetation, but prevent re-establishment of desirable species even after perennial pepperweed control. This experiment examined integrated management strategies with the goal of maximizing perennial pepperweed control and establishment of desirable native vegetation. The experiment was conducted at two sites in Lassen County, CA. Both sites were heavily infested with perennial pepperweed and lacked competing vegetation. The experimental design was a split-split-randomized block with four replications. Site preparation treatments included winter burning, summer and fall mowing, winter grazing, and fall disking. These treatments were designed to remove thatch to facilitate herbicide application and reseeding of desirable perennial grasses. Herbicide treatments included chlorsulfuron, 2,4-D, or glyphosate applied at the flower bud stage. Revegetation treatments included no seeding and no-till seeding of native perennial grasses. Most site preparation plus herbicide combinations reduced perennial pepperweed cover > 85% compared to the untreated control, although treatment efficacy was variable between sites and years. Burning, grazing, mowing, or disking in combination with herbicide treatment and no-till seeding was necessary for successful native perennial grass establishment. Burning or mowing with yearly 2,4-D applications for 3 yr gave the best combination of perennial pepperweed control and native grass establishment. Chlorsulfuron caused chlorosis and stunting to western wheatgrass, basin wildrye, and beardless wildrye at both sites when applied the spring before seeding. No treatment offered complete weed control, suggesting follow-up spot herbicide applications are needed for long-term perennial pepperweed suppression. These results provide several successful integrated strategies for control of perennial pepperweed and revegetation to a desired native perennial grass community.

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