Better Globe Forestry Ltd. (BGF), our mother company, conducts research & development in several areas that affect and add value to our business and interests, and in collaboration with other research institutes for synergy effects. Our major areas cover:
In order to plant all year round, trial plantations have been conducted with Mukau in the dry season. In Kiambere, 1 hectare blocks of mukau were planted in all months from June to December 2008 and 2009.
Different watering regimes were tried, with the most satisfactory being 4 to 5 liters per week depending on the month (May-July and November-January being colder, hence 4 liters. February-April and August-October being warmer, hence 5 liters). To avoid run-off, the water was poured manually into small basins constructed around each seedling. At a moistened area of 20 centimeter diameter, this dose of 5 liters corresponds to a rainfall of 159 millimeter (1 millimeter of water per square feet meter being equivalent to 1 liter).
The irrigation was done on a top soil of loamy sand and a subsoil going towards sandy loam. In both cases therefore, a relatively high presence of sand, easily penetrable by water and with relatively low moisture retention capacity. The effectiveness of this operation is however greatly enhanced by mulching. This has not been the subject of research so far, but a grass/weed mulch of 5-10 centimeters thick with a diameter of 50-60 centimeters is applied as a standard measure around one-year-old seedlings. However, this mulching is degraded by termites, and has to be renewed every three months. Plans are under way for trials using chipped wood mulch.
Other measures of water conservation include elimination of competing vegetation and construction of small individual water catchments around each seedling. Indications are that chemical weed elimination by a herbicide (e.g. glyphosate) is more beneficial than hoeing, because of less damage to superficial roots around the seedlings. Using a herbicide also diminishes erosion as the dried rests of grasses and weeds are left standing and act as a break to run-off, thus favouring infiltration of surface water.
Half-moon shaped - and other small catchments - are likely to trap more water, but research is needed to study the effectiveness, including the cost, of other kind of catchments, like negarims.
A first series of soil improvement research trials was done in 2009 to determine the effect of fertilizer on survival and growth of Mukau. Different doses of a commercially available agricultural fertilizer were applied, with clearly discernible effects on survival, growth and health of Mukau seedlings. The fertilizer used so far (Mavuno) has a high phosphorous content, good for kick-starting a vigorous root system, and also includes trace elements like zinc (Zn) and boron (B).
Initial results show that an application of 50 gram at planting seems to be the best option so far. Growth and vigor are enhanced, and possibly resistance against the red spider mite (Tetranychus urticae) though more research has to be done for confirmation. This research was done in cooperation with the University College of Ghent, Belgium, as part of a Master of Science (MSc) thesis.
Another series of trials is under way, regarding fertilizer of one-year-old mukau plantations, as well as defining the components for an ideal tree fertilizer for red tropical soils in drylands.
Better Globe Forestry is working with the Kenya Forestry Research Institute (KEFRI) on a strategy for enhancing the genetic quality of mukau by amplifying the selection of plus-trees nationwide and applying a mass-selection of the best material. This is still in the planning stage, but is definitely the way forward for a sound breeding program. Already, KEFRI has a collection of superior trees and the idea is to enlarge this collection to cover a wider variety of genetic material. The next step will be to clone superior trees and cross them.
KEFRI also has a unique expertise of genetic variability of Acacia senegal, both nationally and internationally, and provenance trials have been planned to compare yield in gum arabic, based on KEFRI’s Kenyan collection. Harvesting of seeds started in 2010.
Mass production of genetically identical and superior germplasm is the objective of this research. The research is conducted by the University College of Ghent (Belgium) in collaboration with the Faculty of BioEngineering of Ghent University.
Researchers are fine-tuning the method (called "protocol") for multiplying tiny pieces of plant tissue towards healthy rooted seedlings that can be removed from the laboratory, passed to the nursery for hardening-off and planted in the field. For the moment, the researchers are concentrating on consistent formation of a healthy taproot, the last obstacle regarding mukau.
This research activity is concerned mostly with identifying the pests and diseases that attack both species. It is conducted with support from KEFRI’s phytopathologists and the University College of Ghent.
Mukau (Melia volkensii) suffers from various fungi in the nursery, like Fusarium spp. and others. The leaves of young seedlings can be attacked by the red spider mite (Tetranychus urticae) notably in a prolonged spell of dry weather, while a cancer from a not-yet-confirmed bacterial origin, can attack the bark and wood of young trees, provoking gummosis.
The ideal silvicultural management schedule of mukau is a work in progress. Information about spacing, pruning and thinning in monoculture plantations is gradually merging into a coherent management table. Several crude models have been established, such as the one below:
|1||Clearing, ripping and harrowing||By bulldozer, ripping down to 80 cm, and tractor|
|1||Pitting||20x20x20 cm, 400 pits|
|1||Planting||400 seedlings + 20% beating up (5x5 meters planting distance)|
|1||Fertilising||50 gram fertilizer per seedling|
|1||Maintenance||Ploughing or harrowing, 15-20 cm deep|
|1||Spraying with herbicide||Close to the trees where the harrowing did not reach|
|1||1st pruning||Up to 1 meter, at 4 months (secateurs and by hand)|
|1||2nd pruning||At 6 months (pruning saw, secateurs and by hand)|
|1||3rd pruning||At 8 months (pruning saw, secateurs and by hand)|
|2||Maintenance||Ploughing or harrowing, 15-20 cm deep, 4 times|
|2||Fertilising||200 gram fertilizer per tree, mixed with superficial soil layer|
|2||Spraying with herbicide||Close to the trees where the harrowing did not reach|
|2||4th pruning||With ladder, selectively removing branches|
|2||5th pruning||With ladder, selectively removing branches|
|3||6th pruning||With ladder, selectively removing branches|
|3||Maintenance||Ploughing or harrowing, 15-20 cm deep, 4 times|
|4||7th pruning||Up to 5 meters|
|4||Maintenance||Ploughing or harrowing, 15-20 cm deep, 4 times|
|5-7||Maintenance||Ploughing or harrowing, 15-20 cm deep, 2 times|
|8||Thinning||1/4 or 100 trees, DBH 25 cm, 5 meters|
|8-19||Maintenance||Ploughing or harrowing, 15-20 cm deep, 2 times|
|20||Felling||300 trees, DBH 50 cm, 5 meters|
|MAI - Mean annual increment (m3/ha/year)||11.16|
Serious work still needs to be done on optimization of pruning schedules, while the concept of a single thinning can be challenged, as superior genetic material is not yet available. The number of thinnings is related to planting distance, as thinnings are only a means to eliminate inferior material and favor better quality trees.