Elita Chikwati Acting Features Editor
ENDOWED with hugely popular flavours known to satiate various inter-continental tastes, Zimbabwean tobacco currently generates over US$600 million revenue for its agro-based economy annually.
This distinction and charm aside, the production of the golden leaf has in recent times come under heavy scrutiny from environmentalists who are naturally incensed by the deforestation levels the curing of the crop has effected on the environment. The bulk of farmers rely on wood for curing the golden leaf.
Some international organisations have even been threatening to ban buying tobacco that has been produced in an unsustainable way that includes cutting down trees for curing and child labour among other practices.
Deforestation caused by growers cutting down indigenous trees for curing tobacco has affected the industry.
A number of initiatives have been put in place by the stakeholders in the tobacco industry including the Tobacco Industry and Marketing Board, Forestry Commission, Kutsaga Research Institute and some non-governmental environmental organisations to reduce deforestation.
Government also introduced a tobacco levy, which will be used for promoting tree planting in areas where the golden leaf is produced.
Some tobacco contractors have also been encouraging their growers to plant trees for tobacco curing by distributing tree seedlings and encouraging woodlots.
The TIMB seeks to enforce additional minimum standards for sustainable tobacco production for both merchants and tobacco growers.
For instance, the establishment of woodlots, adoption of fuel-efficient technologies, use of renewable sources of energy and eliminating child labour.
The board is also working towards reviewing the existing legal framework to enforce sustainable tobacco production.
There has also been an increase in research and development of curing systems that can burn coal more efficiently and at the same time reducing the carbon foot-print of coal on the environment such as the use of catalytic convertors to reduce carbon emissions from burning coal.
The tobacco leaf market has been demanding better traceability from input procurement through to the market at the international level, as the tobacco supply chain has come under sharper scrutiny.
Tobacco best management practices and good agricultural practices are therefore being accepted as routine production requirements in many tobacco growing regions including Zimbabwe.
Forestry Commission spokesperson, Ms Violet Makoto, said 262 00 hectares of forests were destroyed annually with the tobacco sector contributing about 15 to 20 percent of that damage.
“The sector response to that problem is the Tobacco Wood Energy Programme that we are rolling out in many communities inclusive of the commercial tobacco growing sector and small holder farmers in communal areas.
“The TWEP is promoting the growing of fats growing trees such as the eucalyptus trees which can be used for tobacco curing. So far the large uptake has been in the commercial sector since they have enough and which they can allocate for woodlots. For small-scale farmers we are promoting community woodlots of the same species and a farmer can start harvesting after five to six years.
“Research is also ongoing for other tree species with similar or faster growth rate, which can be used for the same purposes,” she said.
The Tobacco Research Board has been conducting research on energy efficient curing barns to ensure tobacco is grown and handled in a sustainable way.
The use of renewable fuel sources and reduction in fuel-wood requirements through the development of more efficient barns or alternative curing systems is one such initiative.
The TRB embarked on a project to modify a fuel-efficient smallholder barn, the rocket barn, originally designed in Malawi, to suit Zimbabwean conditions.
This was done in partnership with the tobacco trade, namely BAT/Northern Tobacco and Tribac (now Premium Tobacco International).
TRB acting CEO Mr Oswell Mharapara said the Zimbabwean version of the Rocket barn was officially launched at Kutsaga Research Station in 2011.
The rocket barn derives its name from its ability to draw in dry air using exhaust smoke, rather like a rocket which gains its upward thrust from exhaust fumes.
“This is an efficient barn which requires only 47-50 percent of the fuel wood required for a conventional barn to complete a curing cycle. It has been adopted by most small scale growers and is widely used in Zimbabwe,” Mr Mharapara said.
“In 2015, the TRB completed another project that was aimed at developing another low-cost and fuel efficient barn later named the Kutsaga Counter Current One barn (KCC1).
“The efficient heat exchange system of this barn has since been retrofitted on some conventional barns across the tobacco growing districts under a programme sponsored by the Research Council of Zimbabwe, resulting in reduced fuel wood requirements”.
TRB research and extension executive director, Dr Susan Dimbi, said the KCC1 was evaluated for three seasons to establish its performance in terms of leaf cure quality, energy efficiency and the average time it takes to complete a curing cycle.
She said the results of the trials indicated that the barn turn-round time (time taken to complete a curing cycle) was seven days. The barn can consistently maintain a seven-day curing period because of its superior convective air circulation.
“The KCC1 barn has an advantage in that it requires 3. 5 kilogrammes of fuel wood (eucalyptus) to cure a kilogramme of tobacco. This is very comparable to the rocket barn which requires 4 kilogrammes of fuel wood per every kilogramme of leaf cured.
“This high fuel use efficiency is attributed to the capacity of the KCC 1 barn to effectively control temperature, humidity and airflow conditions in the curing room, factors that are important in tobacco curing,” Dr Dimbi said.
According to the TRB, the KCC1 barn produces high quality cures owing to its capacity to cure a batch of tobacco within the normal seven-day period, its superior heat transfer capacity as well as its ability to maintain stable and uniformly distributed air temperature and humidity conditions in the curing room.
The board indicated that the barn temperature readings observed by growers during the colouring stage were more likely to be accurate and not a mere indication of the temperature of ambient air entering the curing room as may be the case with other barns that do not preheat incoming air.
The Kutsaga Research Institute is offering farmers KCC1 barn designs and building plans for free.
An option to retrofit the KCC1 heat exchanger system onto older inefficient barns is also available for growers who would want to improve the curing efficiency of these older barns. This exercise has been ongoing for a while for growers and tobacco contractors who indicated interest.
A number of farmers said they welcomed the idea and encouraged contractors to help in the construction of the curing structure.
Karoi farmer, Mrs Emeria Kanyonge, said she understood the impact of cutting down trees without replacing them but sometimes there were no other available options to get fuel for curing.
“We are now planting trees. Whenever we go to sell our crop at the floors we also get lectures on the importance of planting trees and reducing deforestation. Hopefully we can access the new energy saving barn,” she said.
Another tobacco grower from Mvurwi, Ms Rosemary Wiriamu, said contractors and banks should offer farmers loans so they can construct barns.
“We are willing to pay for the infrastructure but resources may be constraining. We are also working with the local leadership to discourage the cutting down of trees in our area,” she said.