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Showing papers on "Undergrowth published in 1993"


Journal ArticleDOI
TL;DR: Larval populations appeared in late April through early May, peaked in abundance in late June and early July, diminished through late summer, and disappeared in midautumn as the ground began to freeze.
Abstract: Microclimatic and vegetative effects on the population size and activity patterns of larval Eutrombicula alfreddugesi Oudemans, 1910 (Acari: Trombiculidae), were investigated in Nebraska between latitude 40 degrees 0'0" N and 40 degrees 1'21" N. Larval population densities along a forest edge were greatest in areas of high relative humidity, moderate temperature, low incident sunlight, and increasing substrate vegetation. Although chigger populations existed throughout the forest edge, larger populations concentrated in short- to tall-grass transition zones. Chiggers were rarely found in the undergrowth beneath the tree canopy. Chigger activity correlated with a microclimatically driven diurnal rhythm. Activity was greatest during the late afternoon-early evening, between 1530 and 1930 hours (CDST). Larval activity dropped to low levels and remained so until sunrise; this period of reduced activity occurred between 1930 and 0530 hours. Small increases in larval activity occurred around sunrise (approximately 0600-0700 hours). Between about 0700 and 1530 hours, larval E. alfreddugesi were inactive and did not respond to normal sampling stimuli. Larval populations appeared in late April through early May, peaked in abundance in late June and early July, diminished through late summer, and disappeared in midautumn as the ground began to freeze.

62 citations


Journal ArticleDOI
TL;DR: The habitat requirements of the Tasmanian Bettong were investigated by assessed density at 20 sites covering a broad range of dry sclerophyll forest types throughout the species' range and it was suggested that since mycorrhizal fungi develop and sporulate well in soils of low fertility, this factor may be important in indirectly influencing bettong numbers.
Abstract: The habitat requirements of the Tasmanian Bettong (Bettongia gaimardi) were investigated by assessed density at 20 sites covering a broad range of dry sclerophyll forest types throughout the species' range. There was no consistent relation between the density of bettongs and the floristics of an area. Bettongs did not occur in areas with dense undergrowth. However, the occurrence of an open undergrowth did not guarantee the presence of bettongs. The abundance of bettongs on areas with an open undergrowth was related to the extent of mycorrhizal root development, sporocarps of mycorrhizal fungi forming the major component of the diet of bettongs. The highest densities of bettongs occurred in areas with infertile soils. It was suggested that since mycorrhizal fungi develop and sporulate well in soils of low fertility, this factor may be important in indirectly influencing bettong numbers.

26 citations


Patent
24 Sep 1993
TL;DR: In this paper, a method for controlling weeds and undergrowth and for treating plants in agricultural settings is described, characterized by first applying a spray of hot water to the plant, and then applying a foam blanket to the sprayed plants, whereby heat from the hot water spray is held against the plants.
Abstract: A method for controlling weeds and undergrowth and for treating plants in agricultural settings is disclosed. The method is characterized by first applying a spray of hot water to the plant, and then applying a foam blanket to the sprayed plants, whereby heat from the hot water spray is held against the plants.

23 citations


Journal ArticleDOI
TL;DR: Ruminant animals preferred broad leaved plants more than other botanical groups found in oil palm plantation, and metabolizable energy available (MEA) models can be used for predicting available energy (MJ/ha/day) from the system for grazing ruminants.
Abstract: The availability of undergrowth is essential for integrating ruminant animals into oil palm plantations. This is because undergrowth can be used as a feed resource for ruminants. This type of production system has the advantage of diversifying income and controlling weeds in the plantation. At least fve botanical groups of herbage can be found in oil palm plantations, namely, grasses, broad leaved plants, legumes, ferns and palms. Grasses were found in abundant through all palm ages. Most grasses are tolerant to higher light intensity and some are shade-tolerant. This study showed that in the early stages of oil palm crop development, sun-loving species tend to dominate the field, mostly broad leaves and legumes, but they will gradually be replaced by shade-tolerant plants when the canopies close. Concentration of metabolizable energy in herbage on offer was 4.6 to 7.0 MJ/kg dry matter. Crude protein content of grasses, broad leaves, legumes, ferns and palms are 11.5%, 15.4%, 16.3%, 12.5% and 12.0%, respectively. Ruminant animals preferred broad leaved plants more than other botanical groups found in oil palm plantation. This paper showed that metabolizable energy available (MEA) models can be used for predicting available energy (MJ/ha/day) from the system for grazing ruminants. This is because MEA model was developed based on both quality and quantity of herbage present in the ecosystem.

16 citations


Journal ArticleDOI
TL;DR: In this paper, the characteristics of spatial heterogeneity in a human-dominated landscape, vegetation and community structure of pine (Pinus densiflora andP. rigida) forests were studied at rural Teokseong-ri in Chollanam-do, in the southwestern part of Korea.
Abstract: To elucidate the characteristics of spatial heterogeneity in a human-dominated landscape, vegetation and community structure of pine (Pinus densiflora andP. rigida) forests were studied at rural Teokseong-ri in Chollanam-do, in the southwestern part of Korea. Daily removal of undergrowth for firewood affects the stratification and species composition in the community. In general, stratification of the pine forest develops in proportion to its distance from the main habitat of farmers, involving the residential and cultivated land. In pine forests near the main habitat of farmers, sun-demanding herbaceous plants grow well, while in remote forests, Fagaceous plants such asQuercus serrata, Q. actissima andCastanea crenata grow well. This zonation results from the fact that removal of undergrowth is greater in the forest near the main habitat of farmers, than in the remote forest. Construction and maintenance of graveyards, however, prevents development of stratification of the forest even in remote stands.

15 citations


Journal ArticleDOI
TL;DR: Phytosociological investigations of the undergrowth in vineyards in the southern part of the Upper Rhine region, southwestern Germany, over many years are briefly reported and characteristic species, Allium vineale and Geranium rotundifolium are analysed.
Abstract: . Phytosociological investigations of the undergrowth in vineyards in the southern part of the Upper Rhine region, southwestern Germany, over many years are briefly reported. Besides my own data collected over nearly a decade, appropriate releves of earlier authors have been included for comparison. The cultivation regimes have changed more drastically in the course of time - and continue to do so - than they have in other types of agricultural types. The principal cultivation methods are: mechanical soil movement by tilling, herbicide application, and mulching (see Fig. 1). These three types of measures tend to be applied in alternation, both temporally and spatially. Their effects are very different in intensity and time of action, and consequently they cause varying species combinations to build plant communities (Table 1). The concept of strategy-type is discussed and the approach of ‘key characters’ in the sense of Grubb is stressed. Such traits of adaptive value for important species in the vineyard undergrowth are presented in Table 2, for the aspects life form, developmental rhythm, and diaspore formation and dispersal. The combination of such population biological parameters yields a number of strategy-types. In the community description the concept of agroform is used, i.e. a subtype of a plant community brought about by a special agricultural technique. Frequent soil movement results in the dominance of therophytes: the Stellaria media- ‘agroform’ of the Geranio rotundifolii-Allietum Tx. 50; mulching promotes perennials with runners, leading to a Poa trivialis-Lolio-Potentillion community (Wilmanns 1989); moderate spraying with herbicides promotes geophytes, winter annuals, woody plants and succulents: Bromus sterilis- agroform of the Geranio-Allietum. As examples of characteristic species, Allium vineale and Geranium rotundifolium are analysed.

4 citations