The results showed that tree growth and biomass production were better in black wattle alley cultivation than in association with the fever tree. The average dgl black wattle after 12 months was 48mm and the average dbh was 36mlll. A tree pruning was done to one-year-old black wattle throughout the trial and the prunings produced approximately 5.6t/ha of fresh foliage biomass in the association with maize and cowpea and 4.5t/ha in the association with pumpkin.
Changes in the number of black banded twigs in the row with maize and sweet peas as joint crops (mcb), in the row with pumpkins (pb) and in the no-crop.
CHAPTERl
AGROFORESTRY - THE INTERFACE BETWEEN AGRICULTURE AND FORESTRY
The bark of black wattle has a high economic value when used in the tannin industry (Duke, 1983; Schulze, 1997) and can also be used to produce adhesives and flotation agents (Duke, 1981). Birds often build their nests on the heather branches, which promotes the biodiversity of the site. The aim of the study is to evaluate the potential of black wattle (Acacia mearnsii) and the fever tree (Acacia xanthophloea) in an alley system to determine food, firewood and fodder production of the system.
The fourth objective is to analyze the change in soil nutrients in the area due to the effect of alley planting.
RELEVANCE OF THE STUDY
Mechanized land preparation in forest-based fallow systems: The experience from the eastern Amazon.Agroforestry Systems. Organic Agriculture and Agroforestry: Alleycropping for Mulch Production for Organic Farms in the Southeastern United States. Agroforestry Systems 61: 79-90. Fireless alternative to slash and firewood for shifting cultivation in the eastern Amazon region.
BLACK LAW (Acacia mearnsii De Wild.) AND FEVER TREE (Acacia xanthophloea Benth.) UNDER ROWS WITH CORN,.
BLACK WATTLE (Acacia mearnsii De Wild.) AND THE FEVER TREE (Acacia xanthophloea Benth.) UNDER ALLEYCROPPING WITH MAIZE,
3 Yes Yes No No encourage immobilization of N and P or reduce .. the rate of mineralization of organic matter despite high levels of N and P in plant biomass. In the second sampling period, the deficiency of K was 70 kglha and 100 kg/ha under spawning crops with black guard and under spawning with the fever tree, respectively. The amount of P in deficiency was 20 kg/ha for the control, 70 kg/ha for black spawn and 100 kg/ha for fever tree spawn in the first soil analysis.
In the second analysis, P deficiency was 20 kg/ha for the controls, 50 kg/ha for the black sea alley planting, and 75 kg/ha for the fever tree planting. Deficiency was in the amount of lOkg/ha under black valley planting and 70 kg/ha under fever tree planting in the first cropping season. Potassium was found to be deficient only in the first season under alley cultivation.
The yield of pumpkins under alley cultivation was 12.7 tons/ha during the first season and decreased to 8.5 tons/ha in the second season. The fresh biomass of cowpea was 2t!ha and 2.6t!ha in the first growing season and 3.7t!ha and 7t/ha in the second season under alley cropping and conventional farming system, respectively. However, crop yield and biomass under alley cropping were not as great as controls and the difference was statistically significant (P<0.05), especially in the second growing season.
Conversely, weed and shading control was much more efficient in the second cropping season and the result was increased crop yield and biomass of maize and pea. Under planting black squash and pumpkins, competition was not a problem in the first planting season because the squash grew very quickly suppressing weeds while tolerating shade from the trees. The annual increase in the diameter at ground level of the black eyelash was about 48 mm and the height increased by 4 m/year.
Research is also needed to determine the ideal ratio of black wattle in the feed to avoid animal intoxication due to the excess of tannin.
BLACK WATTLE (Acacia mearnsii De Wild.) IN ALLEYGRAZING SYSTEMS
Leng (1997) found that the concentration of saponins in the foliage fed to cattle was responsible for the low productivity of young cattle. In another study, Wheeler et al. 1995) observed that mimosine, a compound present in the leaves of Leucaena sp. Beck and Goodricke (2002) observed that wild and domesticated animals browse on black girdle seedlings, where cattle and goats also browse on older trees.
The first was used to determine the DM of trees, after oven drying at a temperature of 65°C for 4 days. The feed analysis consisted of the determination of acidic detergent fibers (ADF) and neutral detergent fibers (NDF). 14 tons/ha in the control and 8.11 tons/ha and 9.24 tons/ha under grazing and the control in the second season respectively.
In this study, during the first growing season without application of fertilizer or mulch, DM of E. In contrast, significant differences (P<0.05) were observed in both treatments and blocks in the second season (Table 3.5). Figure 3.2 compares the fresh biomass during grazing and for the control in both seasons.
Pruning the one-year growth of the black wattle yielded 2.68 tonnes/ha of leaf DM during the first pruning. Agroforestry systems for sustainable crop production in the tropics, with special attention to West Africa.
EQUATIONS TO PREDICT EARLY GROWTH AND BIOMASS OF BLACK WATTLE UNDER ALLEYCROPPING
Tree height is an indicator of the growth potential of the species in a particular location. The purpose of this part of the study is to create tree growth equations to predict tree biomass and volume based on tree diameter and height, as well as equations that express changes in tree diameter and tree height as a function of age during early growth period. The test consisted of calculating the coefficient of determination (R2) and standard error (SE) of those models using data from the experiment, as done by Jenkins et al.
Early growth comparisons can help predict the woody and non-woody biomass that can be extracted from young jungles formed by invasive black wattle using only their age, mean diameter and/or height, and number of seedlings per unit area to know. in those jungles. To further improve the prediction of Equation 4.2, it can be developed into Equation 4.3, known as Botkin's equation. The parameter al scales the time axis, while a2 provides further flexibility for the shape of the growth curve (Gadowand Hui, 1999).
Alternatively, Hui and Gadow (1993) developed another equation for height prediction (equation 4.8) based on the allometric growth theory, assuming that the growth rate is influenced by a stand trait such as the dominant height. Tree volume is expressed as a quotient of the basal area of the tree and its height. The subsamples were randomly selected from the lower, middle and upper parts of the tree.
These were high due to measurement inaccuracies related to the height of the trees as time progressed. The total fresh usable biomass was a sum of the fresh leaf biomass and the fresh woody biomass, and the relative proportions of each part are given in Equation 4.36.
CHAPTERS
THE PROBLEM OF ANIMAL DAMAGE AT THE UKULINGA FARM
This is usually achieved through the use of fear-inducing stimuli that increase the animals' fear of going to the areas where crops or livestock are located. The most common visual practice with fear-inducing stimuli is the use of human-shaped scarecrows. Auditory stimuli consist of the use of sound or noise to induce fear in the animals.
Other methods of fear-inducing stimuli include the use of live predators and guard dogs (Conover, 2002). However, in many cases translocation appears to be one of the best methods of controlling nuisance wildlife. Fertility control is used to reduce the fertility of the wild animal population in order to control its numbers.
The first is to visit the sites where the damage occurs and directly measure the extent of the losses. An alternative way to estimate the economic impact of animal damage is the lost opportunity cost analysis. Assessing animal damage is not an easy task, but it is an important tool to assess whether or not animals are economically compromising production objectives.
In the agroforestry plots on the Ukulinga farm, losses due to animal damage were not estimated. Although the costs to be paid to the guards in three months amounted to R15,000 for salaries, plus R1OOOO spent on arranging the facilities to prepare the farm for temporary accommodation.
GENERAL CONCLUSIONS
Tree height was characterized by an exponential behavior expressed by the Schumacher function in the equation h = 873.97e-9.l8/age, and the relationship between total tree volume and dbh was characterized by the Schumacher-Hall model in the equation In V = 21n dbh + I h - 4.85. The usable volume from black prunings was 55% of the total wood volume, while the foliage from prunings represented 82% of the total biomass harvested. The units are mm for diameter, cm for height, cm3 for volume and g for biomass, and age is expressed in months.
During the current study, monkeys and cattle caused some damage in the trial where the losses were estimated at R25 000. 2 To extend the time between injection operations, it is often advisable to apply more lime than recommended above. 5 Where the soil P test of a sample is abnormally high (>120 mg/L), and the sample is truly representative of the entire field, no fertilizer may be applied until test levels indicate a requirement.
Details are given in the pamphlet "Nitrogen fertilization: AUOuting for N mineralization and residual N" available from AlanManson or Valko Katusic. 8 Ensure that the total combined Nand K applied in the band at planting does not exceed 80 kg/ha. 2 Where soil test P levels are considered adequate, but are less than 120mg/L, an initial application of 20kg P/ha is recommended 10 promotes initial plant growth.
3 Where the soil P test of a sample is abnormally high (>120 mg/L), and the sample is broadly representative of the entire field, no fertilizer P should be applied until test levels indicate a P requirement. 3 Where the soil P test of a sample is abnormally high (>120 mgtL), a response to P fertilizer is unlikely.
