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The development of established shrub seedlings in persistent historical reindeer milking groundsLindén, Elin January 2015 (has links)
This study focuses on how established shrub seedlings (Salix myrsinifolia x phycilifolia and Vaccinium vitis-idaea) develop in historical milking grounds. Historical milking grounds are cultural remains from the intensive reindeer herding era when the Sami migrated with closely controlled herds. Although the places were never fenced, the high concentration of reindeer close to the tenting grounds created patches of grass and forb dominated vegetation in areas outherwise dominated by deciduous or ericoid shrubs. Despite about 100 years of abandonment the shrubs have not come back and the milking grounds are still clearly visible in the landscape. One theory why the former milking grounds are so stable is that shrubs cannot establish from seedlings due to unfavorable abiotic conditions, or due to competitive dominance of already established forbs and grasses. I tested this hypothesis by planting shrub seedlings in the milking grounds and in reference areas, with and without neighboring vegetation and investigated seedling survival and growth. The results show that shrub seedlings are able to both survive and develop in milking grounds suggesting that the seedling state is not the limiting factor in shrub encroachment in the milking grounds.
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Effect of Spring Grazing by Cattle on Growth and Survival of Shrub Seedlings Interplanted in Crested WheatgrassMcConville, Lynn M. 01 May 1986 (has links)
A short duration-high intensity grazing trial was conducted in spring of 1985 to determine whether shrub establishment in crested wheatgrass pastures could be enhanced through spring grazing by cattle, or by fertilization of shrub seedlings. Data was collected on diet selection by cattle during spring grazing, and on subsequent shrub growth and survival. Shrubs studied were transplants of sagebrush, Artemisia tridentata, fourwing saltbush, Atriplex canescens, bitterbrush, Purshia tridentata, and one year old bitterbrush seedlings.
Cattle did not browse sagebrush or fourwing saltbush transplants, but utilization of bitterbrush transplants and seedlings averaged 15 and 42 percent, respectively. Shrub selection by cattle was unaffected by grazing pressure or fertilization.
Fertilization increased growth of sagebrush transplants but had no effect on survival. Trampling of shrubs was greater than anticipated. Trampling reduced growth in sagebrush, and reduced survival of both bitterbrush and sagebrush transplants. Browsing reduced growth of bitterbrush seedlings, but increased growth and survival of bitterbrush transplants. Despite adverse effects from trampling and browsing on some shrubs, the overall effect of spring grazing of crested wheatgrass by cattle was to enhance establishment of fourwing saltbush and bitterbrush transplants. Spring grazing had no measurable effect on establishment of sagebrush transplants or on survival of one year old bitterbrush seedlings.
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