Shade-based control of Imperata cylindrica: tree fallows and cover crops

Abstract

lmperata is shade-intolerant, although little is known of the relative roles of competition for light, water and nutrients in suppressing its growth. Shading of lmperata results in reduced carbohydrate storage, reduced rhizome and tuber-bulb production, reduced shoot dry weight, increased susceptibility to competition, increased susceptibility to herbicides and decreased vigor/regeneration. Herbaceous cover crops in the genera Calapogonium, Crotoleria, Mucuna and Pueraria have been shown to effectively suppress Imperata growth and can be used to prevent and in some cases eradicate lmperata. Tree fallows with fast-growing species such as Sesbania sesban, Acacia nilotica and Leucaena leucocephala can improve soil physical and chemical properties and suppress weed growth. Forest plantations have been successfully used, particularly with the use of moderate to high tillage, weeding and fertilizer inputs to suppress lmperata growth. These plantations produce marketable wood and reclaim the site for other uses. Additional research is needed to evaluate the specific nature of competition and allelopathic effects from Imperata. Continued evaluation of tree species and provenances for lmperata suppression, forms of tillage after woody fallow crops and the constraints to adoption of cover crops and trees as Imperata control measures are also needed.

Biomass and carbon distribution on Imperata cylindrica grasslands

“…This implies that the conventional and mechanical elimination of this grass will never succeed, because of the difficulty of removing the deep rhizomes. Measures could be combined with a sound and environmentally friendly chemical application before shade-based (Macdicken et al 1997) and soil fertility improvement measures (Santoso et al 1997) could effectively control this grass. The magnitude of root biomass of 12.4 mg ha -1 was in the range of that of coolseason grass and switchgrass of riparian buffers of 10.9-16.8 mg ha -1 (Tufekcioglu et al 1999(Tufekcioglu et al , 2003.…”

“…Shade, repeated herbicide application, and mechanical control have all been used to control I. cylindrica (Macdicken et al 1997;Terry et al 1997;Yandoc 2004;Yager et al 2010). Mechanical control is, however, very labor-intensive and the use of herbicide (Glyphosate) is costly and open to environmental risks.…”

“…However, this grass is susceptible to shade (Eussen 1981;Brook 1989;Otsamo 2002) resulting in reduced carbohydrate storage, rhizome, and tuber-bulb production, shoot dry weight, increased susceptibility to competition and herbicides, and decreased vigor and regeneration (Macdicken et al 1997). Plantations of fast-growing trees are, therefore, effective in suppressing and elimination of this grass (Turvey 1996;Otsamo et al 1997).…”

Potentials of the Underutilized Kei-apple (<em>Dovyalis caffra </em>L<em>.</em>): Beyond its Nutritional and Functional Value

“…Home /domestic uses a. Kei-apple for aesthetic and fencing: Kei-apple has strong aesthetic and landscaping potential, which is intensive tree management/ornamental use, its attributes seldom being exploited, and mainly used to beautify. As a boundary, barrier or support, Kei trees can be spaced close together to form an impenetrable hedge around homesteads, gardens and croplands to keep out unwanted animals due to it long thorns [27,11,28]. Kei-apple plants in home gardens are an important part of some traditional/subsistent farming systems, which should be encouraged in developing countries that are characterized by high population densities and the decreasing availability and accessibility of arable crop farming lands.…”

Biology and Control of Cogongrass (Imperata cylindrica) in Southern Forests

“…and hairy indigo (Idigofera hirsuta Harvey) have also inhibited cogongrass establishment (Gaffney 1996), but bahiagrass, bermudagrass, and hairy indigo are non-native and are also potentially invasive in forests and natural areas. In Indonesia, establishment of forests with understory cover crops has been effective in suppressing, but not eradicating, cogongrass (Macdicken et al 1997). Deep shade has been shown to reduce cogongrass establishment (Otsama et al 1995, Ramsey et al 2003; fast-growing legumes such as velvetbean have been used successfully in other countries (Chikoye et al 2002).…”