Colonial govt introduces eucalyptus trees as wood shortage looms 

“Eucalyptus is here to stay,” predicted M.T. Dawe, the head of the Forestry and Scientific Department in his annual report of 1908.
This was after the introduction of eucalyptus trees in Uganda on the orders of the colonial government. This was to prevent the looming shortage of wood, which was the main source of fuel at the time.
The orders directed that eucalyptus plantations be planted in and around the different government missions countrywide.
Writing in the Uganda Journal volume 36 of 1972, P.K. Karani says around 1907 firewood and building poles from natural vegetation was becoming scarce.
“Most of the natural forest on the Entebbe peninsula had been cleared and the Kampala firewood supplies were being collected for as far east as Namanve and Namilyango,” he writes.
At the time, nsambya, muvule, markhamia platycalyx and chlorophora excelsa, in that order, were the dominant trees in the protectorate.
To effect the governor’s orders, the Forestry Department imported seeds from Australia. The species imported included cebra, polyanthemos schaner, hemipholia muell and teriticornis domin. 
After the department got the seeds, a tree nursery was established at Entebbe. The seedlings from the Entebbe nursery were then sent to the administrative officers in Entebbe, Kampala and Jinja before being spread out to different parts of the country.
The seedlings were not only cultivated in plantations, but also along main roads to beautify and make the towns green. 
Besides being planted for firewood and poles for construction, some species had a health importance. 
In swampy areas around towns, eucalyptus trees were specifically planted as a biological control against the  anopheles mosquitoes that carry malaria parasites.
Writing in the Uganda Journal volume 2 of the of 1934, G.H.E. Hopkins says: “An important fact in connection with control of mosquitoes by means of tree planting is that the dangerous species of anopheles do not like shades. For this reason any rain pools which may form in wet weather in an area closely planted with trees will not be a source of malaria carrying species, because of the denseness of the shade.”
Two species, E. Grandis and E. Robusta, were planted specifically for this purpose. In Kampala they were planted in Kintate (golf course) other places were Masaka and Fort Portal.
Of the species introduced in Uganda, eucalyptus grandis and eucalyptus teriticornis outperformed the rest. 
Eucalyptus teriticornis did well in Ankole region and it was nicknamed rwambaguta, or kakoba. It got the Rwambaguta name from Nuwa Mbaguta who was the prime minister (enganzi) of Ankole in 1938 when it was popularised in the region. It was also named Kakoba because of the hardness of the timber. It was said to be as hard as ekikoba, a type of hide.
Meanwhile, eucalyptus robusta was planted in swamps mainly because it was very tolerant to water logging and effective in malaria control.
The introduction of eucalyptus did not, however, discourage the planting of native trees such as nsambya, podo (podocarpus milanjianus), musizi (maesopsis eminii) and muvule. They continued being planted, though not on the scale of eucalyptus.
The problem with the local trees though was that they took much longer to grow and were not ideal for plantations. The nsambya tree, for instance, was found to be very difficult for tree farming.
“It is slow growing and yields poor, crooked and usually forked stems. Slow growth called for many years of tending before plantations were established,” Karani writes.
The muvule tree was known to be attacked by the gall fly. The eucalyptus tree had a superior growth than any of the ingenious trees.
According to the 1913 Forestry and Scientific report, “Eucalyptus seedlings have made good growth.  Such rates of growth were naturally more attractive than nsambya.” 
According to Karani, the eucalyptus seeds brought from Australia had adaptive ability to survive in exotic environments.
“In this country, eucalyptus species can be grown in many areas which differ markedly in soil and climatic conditions... [they] can be grown with varying success in places which are as dry as Karamoja and as wet as Entebbe,” Karani writes.
Because provision of firewood and building poles were the main reasons for the introduction of eucalyptus trees, the needs did not require very mature trees. As a result, the trees needed were not only those that could mature fast, but with the ability to coppices fast.
Coppice is the growing of new shoots from the stump when the original stem has been cut. Eucalyptus tereticornis was planted in Entebbe because it coppiced easily so as to provide constant source of firewood to government officers residing in Entebbe.
Like most plants, eucalyptus hybridises easily. In the case of Uganda, there is a hybrid called eucalyptus teriticornis soroti, a hybrid between eucalyptus grandis and eucalyptus tereticornis. 
“One of its characteristic is that its stem form is usually straighter than the normal eucalyptus tereticornis,” writes W. Kreik in the 1970 Food and Agricultural Organisation (FAO) report about the performance of indigenous and exotic tree species. 
The soroti hybrid is also grown in other places in Uganda were eucalyptus grandis does not survive.

Justification
Eucalyptus was grown on a plantation scale over the indigenous trees because of its higher volume production.
“Maesopsis eminii (musizi) is one of the fast growing tree in Uganda, its volume production per hectare per annum is unlikely to be more than 10 cubic metres of wood whereas eucalyptus grandis grown in the same site can produce more than 30 cubic metres per hectare per annum,” said L.D. Pryor at the FAO world symposium on man-mad forests and their industrial importance in Canberra in 1967.

Coming of electricity
With the coming of electricity, firewood ceased being the main source of fuel. Even construction ceased being solely dependent on poles as towns grew. 
“When the many towns were supplied with electricity, the use of firewood for industrial and domestic purposes diminished. With the coming of electricity, there was no need for firewood initially but there was need for the poles to transmit electricity. Namanve plantation ceased producing firewood to producing electric poles,” Karani writes. 
The introduction of electricity did not push firewood to the peripheral as a source of fuel. As towns grew, they attracted people from the rural areas who could not afford electricity. They relied on firewood. 
As the government’s need for firewood waned, other demands for the same appeared. The introduction of tobacco as a cash crop created more demand than had been planned by the government. 
Eucalyptus plantations were established in the areas of Acholi, West Nile, Kigezi and Lango to provide firewood for curing tobacco.
With the advent of industrialisation, more fuel was needed than could be produced. A plan was mooted to cut down Mabira Forest and have it replaced with eucalyptus trees.
“It was announced that a steel mill is to be set up and as steel manufacturing requires carbon and Uganda has no natural coal deposits, the only cheap source of carbon is charcoal. Thousands of hectare of eucalyptus will have to be established in order to meet fuel requirements from which charcoal will be manufactured. It’s most likely that some of the natural forest around Jinja will be converted into eucalyptus plantations,” Karani writes. But the plans never materialised.
As Dawe predicted, eucalyptus has indeed stayed. Its timber is one of the much sought after in the construction business not only to make scaffolds but also to make roofs.