By Chaliafya Katungula
Gone are the days when acquired land was being left to lie idle, today it has become a common trend for Zambians to establish some form of plantation or indeed practice farm forestry. A quick survey has revealed that there are a number of nurseries that have sprang up over the recent years. These engage in the practice of raising seedlings and selling them to clientèle across the country but unfortunately, the majority in this enterprise are not engaging professionals who have silvicultural expertise, thus leading to failure and loss.
The fact of the matter is that this task of growing trees is challenging by the long term nature of forestry, the changing and greater demands of society for forest products and environmental responsibilities as well as the unpredictable nature of fire, pests and diseases. Thus, Successful plantation management requires increased and improved knowledge regarding tree health issues, more effective quarantine, silvicultural practices, and importantly, the establishment of sound breeding and selection programs.
I encourage fellow Zambians that are involved or interested in growing trees to engage trained and qualified forestry professionals with sound knowledge and expertise. This is because tree farming or tree growing involves Silvicultural operations such as site preparation, planting, tree pruning, weed spraying, and fertiliser application to ensure that the plantations are healthy and productivity is optimum.
Everyone should be aware that Planning for a pine/eucalyptus plantation starts several months before the first seedlings are planted. A number of factors need to be considered, including: Size of the area to be planted, Existing vegetation and protection of biodiversity values, Weed infestation, Water movement, Erosion prevention, Location of forest tracks, Soil type and nutrient content. Each stage needs to ensure a maximum rate of tree survival and growth, while protecting and managing environmental characteristics. If the site is a second rotation, the residue of the previous crop of trees is reduced. The site is cultivated to improve soil health and create planting lines. Prior to planting the seedlings, the area should be treated with herbicide (where possible) to control the growth of weeds, reducing competition for valuable water and nutrients
The nursery cultivates young plants from seed or cuttings sourced from genetically superior plants- those with the most desired traits, such as improved palatability and yield—are selected for continued propagation. However, there is a challenge in this area as most nurseries that have emerged in Zambia do not take the criteria of “genetically superior plants” into consideration and are mostly propagating plant material from genetically inferior plants. In reality most Planting material are imported from other countries that have not been bred and selected for local conditions in Zambia. This site-species mismatch adds stress to trees and exposes them to pests and pathogens to which they do not have natural resistance. Additionally, it makes them more prone to diseases caused by opportunistic pathogens, thus, you find a lot of people buying pine and eucalyptus seedlings but experiencing plant failure or low survival rates. Therefore the source of the seedling is important. Always source your seedlings or seeds from a trust worthy source that can assure you that the product you are purchasing sources from genetically superior plant materials.
At about nine months old (about 25cm high), the seedlings are planted at 1,111 trees per hectare using a spacing of 3meters by 3meters. Being close together, the seedlings grow straight as they compete for available moisture, sunlight and nutrients. If required, fertiliser is used to improve tree health and growth. Over the length of a rotation trees are “thinned”, with about 30-50% of trees removed per thinning. This occurs at approximately 10 year intervals, when tree growth slows due to competition. Thinning allows the remaining trees more space to obtain water, light and nutrients from the soil. This allows the remaining trees to establish their optimum rate of growth. Trees removed at first thinning are used for fence posts or other uses such as energy and pulp in countries that have developed pulp and paper industries.
Nursery owners, plant propagators and tree growers should be aware that it is a requirement under current legislation for nurseries be registered and regulated under the Plant Quantine and Phytosanitary Services (PQPS). Further, the forestry Act No 4 of 2015 provides for establishment of private forests. Specifically, section 26 (1) States that an owner or lessee of any land or plantation who wishes to establish a private forest shall apply to the Director, in the prescribed manner and form, for the registration of the area which the person intends to comprise the private forest of pests and diseases that could reduce productivity of Eucalypts and Pine. Therefore, those that are engaged in establishment of nurseries and growing trees should ensure that they abide by the statutes and operate within the confines of the law.
Tree growers should be aware of pests and diseases that could reduce productivity of eucalypts and pines. Prevention of these ailments requires the expertise of forestry professionals. In the eucalyptus category, tree growers must look out for leaf diseases such as Corky leaf spot, Mycosphaerella leaf Disease (MLD), Pseudocercospora leaf disease, Kirramyces leaf disease and Cylindrocladium leaf disease. The stem of eucalyptus tree species also present and manifest diseases of their own nature such as Botryosphaeria canker, Chrysoporthe canker disease and Coniothyrium canker disease. On the other hand the pines are also prone to common diseases such as Dothistroma needle blight and Armillaria root rot.
Seedling mortality at the early stages of plantation establishment in Zambia is mostly affected by Poor planting techniques like planting in shallow pits exposing their roots to heat and sun. It has also been reported that Thinning in Zambian plantations is usually not done and depends in most cases on market demand for timber, rather than on a plantation maintenance schedule. As long as the sale of thinning’s cannot cover the costs of this operation, thinning will not be undertaken and this results in overstocking
Members of the public should not be afraid of engaging into tree growing or farm forestry. Provided they comply with existing regulations and engage forestry professionals, success and productivity is guaranteed. Further, it must be made known that an intimate relationship between farming and forestry exists and is, on the one hand, bilaterally profitable: farming makes available labour and food for forestry, while forestry provides capital for farm development; on the other hand, farming and forestry conflict in the allocation of land, labour, manure, and time. Landowners interested in pursuing forest farming need to examine all internal and external factors that could influence their success. Many new enterprises may require additional skills and expertise of foresters.
The country has in recent years grown the calibre of cadres in the forestry profession. A forester can be found in the public service- usually found at the forestry department offices across the country and those in the private sector. Therefore as we encourage everyone in undertaking afforestation and reforestation, let’s engage forestry professionals so that these efforts are well informed and sustained.
Remember not to buy forest seedlings anyhow but go for those that are from genetically superior plants, sourced from a registered nursery facility.
The Author is Advocate General Forestry Advocacy for Communication, Transparency, Accountability and Research- F(A+C+T+A+R)