The experiment was conducted at the Forestry Research Center, Ethiopia in 2008. Soil was sampled under the canopy of Hagenia abyssinica and from farmland area adjacent to the forest to measure fertility of soils by using the biotest with linseed (Linum usitatissimum L.), barley (Hordeum vulgare L.), and wheat (Triticum aestivum L.) as indicators. The experimental design was a completely randomized design comprising of 20 seedlings per study site. Seeds were seeded into polythene plastic bags. Seedling emergence, germination, and survival rate were recorded. Plant height and root collar diameter were measured. Final weight of fresh biomass was measured, and each component was oven-dried at 70°C. Dry weight was recorded at constant weight. Significant differences ( ) were observed between soil treatments. Plants grown on Hagenia-influenced soils attained better performance, suggesting the beneficial role of Hagenia abyssinica in enhancing soil fertility status which in turn results in higher productivity. 1. Introduction In Ethiopia, land degradation in the form of soil erosion and declining soil fertility is a serious constraint to agricultural productivity as well as economic development [1–3]. Land cover change triggered by agricultural land expansion and heavy livestock pressure are the proximate causes for degradation [4–6]. Some of the noticeable problems of soil fertility loss in the highlands include using dung and crop residues as household fuels and animal feeds, declining fallow periods, soil and organic matter burning (guie), and low use of chemical fertilizers [7]. Though the farming system in most part is mixed crop-livestock, nutrient flows between the two are predominantly one sided, with feeding of crop residues to livestock but little or no dung being returned to the soil [7]. Fertility replenishment can only be sustained if the nutrients removed are returned to the soil through addition. Trees on crop land have potential to improve soil fertility due to their organic inputs with nutrient recycling through mineralization [8–12]. Because soils in many parts of Ethiopia have low fertility, farmers are trying to apply inorganic fertilizers to replenish plant nutrients in their crop land. However, with the rising costs of farm inputs, this is becoming less of an option for the majority who do not have enough cash to purchase fertilizers. Therefore, it is critical to look for an option by examining trees that can improve top soil fertility through addition of litter. Hagenia abyssinica (Bruce) J. F. Gmel is an indigenous broad-leaved
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