Eucalyptus grandis, commonly known as the flooded gum or rose gum, is a tall tree with smooth a bark, rough at the base fibrous or flaky, grey to grey-brown. At maturity, it reaches 50 meters (160 feet) tall, though the largest specimens can exceed 80 meters (260 feet) tall. Mostly the tree is grown and does well several parts of Kenya.
Eucalyptus grandis is an evergreen tree 40–60 m high with a tall straight trunk and 1–2 m in diameter. Crown spreading and thin in open; small and compressed in dense plantations, Its bark white, gray or green, smooth, shedding in long narrow strips. Leaves alternate, lanceolate, 10–20 cm long, 2–4 cm wide, acuminate, inequilaterally, wavy, glabrous. Umbels single at leaf base, 2.5–3 cm long with flattened stalk of 12 mm. The flowers are 5–12, short-stalked or stalkless. Buds pyriform, 10 mm long, 5 mm wide. Stamens many, threadlike, white, anthers oblong with large round gland, Pistil with inferior 4–6-celled ovary, Capsules several, short-stalked, pyriform or conical, 8 mm long, 6 mm wide. The tree has Juvenile leaves that are petiolate, opposite for several pairs then alternate.
The bole is straight for 2/3rds to 3/4 the height of the tree. The bark is smooth and powdery, pale- or blue-grey to white in colour, with a skirt of rough brownish bark for the bottom 1–4 m of the tree trunk
The flowers are bisexual, with fertile male and female organs on the same flower. Pollination is dependent on insects or animal vectors. Like many Eucalyptus species, it has a tendency to out-breed. The tree does well in deep, free-draining soil, and does best on fertile loam or clay-loam soils, but it will also perform well on lighter sandy soils, provided these are deep enough.
E. grandis is used for pulpwood, fuelwood and timber for mining, a 6 to 10 year rotation is common. In most countries, no thinning is done on these short rotations. In Kenya its used for industrial plantations, an 8-year rotation is used with thinning at the ages of 2 and 5 years. A 4-year rotation without thinning is used for production of small wood for domestic purposes. Thinning should be done to 3 stems per stump.
For most types of products, 1 seedling rotation, followed by at least 2 coppice rotations, is common practice. Under natural conditions, E. grandis bears heavy seed crops every 2-3 years. A fully mature tree can produce 2 kg of seed annually.
Seed storage behaviour is orthodox; 4% germination after 10 years open storage at room temperature; viability maintained for 4 years in hermetic storage at room temperature with 11-15% mc; hermetic storage at 4-6% mc and subzero temperatures is recommended; viability can be maintained for several years in hermetic storage at 3 deg. C with 6-10% mc. There are approximately 650 000 viable seeds.
Soya bean (Glycine max) interplanted with E. grandis as part of an agroforestry research project in
southeastern Brazil suppressed weeds without adversely affecting E. grandis survival and growth. Maize and sorghum have also been found compatible with E. grandis. In South Africa, E. grandis planted adjacent to avocado orchards reduces the yields by shading and competing unfavourably with the avocados for light, nutrients and water.
Apiculture: E. grandis blossoms regularly and sometimes heavily but usually provides only small honey surpluses. The tree’s main nectar value is as a supporting species. The honey is amber and strongly flavoured but rather thin.
Fuel: Large quantities of the wood are used for charcoal, for iron smelting, for example in Brazil. The firewood is used for domestic purposes and for curing tobacco, and tea especially in Kenya and Uganda.
Fibre: E. grandis has been used for manufacturing sulphate pulp, for example in Brazil, Uruguay, South Africa and Angola.
Timber: The wood has been used for fence posts, building, transmission and telephone poles, boxes and hooks. It is especially used for boat building, flooring, plywood, panelling and general construction. It can also be used for sawn timber but has tendency to split.
Riverbank stabilization: The tree is too large for most gardens, but makes an attractive tree for large parks and farms, and can be used in riverbank stabilization.
Pulpwood: E. Grandis is the most common short fibre source for pulpwood to make pulp. The fibre length of the tree is relatively short and uniform with low coarseness compared with other hardwoods commonly used as pulpwood. The fibres are slender, yet relatively thick walled. This gives uniform paper formation and high opacity that are important for all types of fine papers. The low coarseness is important for high quality coated papers. Eucalyptus is suitable for many tissue papers as the short and slender fibres gives a high number of fibres per gram and low coarseness contribute to softness