POPLAR, _Populus_.—We have many large plantations of the Lombardy poplar, _P. Nigra_, L., Canadian poplar, _O. Canadensis_, Michx., and the Swiss, Virginian and some of the Carolina poplar, which is the male plant of the same species. Some plantations of the silver poplar, _P. alba_, _P. euphratica_ and _P. simoni_, have also been planted. All may be utilized as auxiliaries in planting mixed woods and timber for cutting. They are very hardy, and the wood is used for packing-cases, boxes, etc. They are planted from grafting twigs 50 centimetres apart, in rows of 2 metres, to be thinned out when necessary. WHITE ACACIA, _Robinia pseudo-acacia_.—North American. Grows to a height of 25 metres by 0·60 metre in diameter; when dry, the wood is excellent, and is used for coach-building, cabinet-making, etc. It grows well, especially in mixed woods, as the saplings are utilized. In timber plantations it must be planted singly as it overruns the ground in a short time. To be sown in rows 25 or 30 kilogs. to the hectare, without any mixture. From the strongest and straightest specimens stock trees are chosen, the others are cut down to the ground every two, twelve or eighteen years. WILLOW, _Salix_.—The willow is very useful for planting woods in damp or low-lying places in the 3rd, 4th, 5th, 6th, 7th, 8th and 9th regions. It is grown from grafting twigs, a metre apart, anywhere. The weeping willow, _S. babylonica_, gives fuel which sells well. The osier willow, _S. purpurea_, _S. rubra_, _S. vitellina_, _S. viminalis_ and _S. amygdalina_, furnish fine and common osiers, which are so much used in basket-making of every kind, and for light wicker furniture for the garden and the beach. It is one of the chief products of the Paraná Islands and others. ELM TREE, _Ulmus_.—The elms we possess belong to the species _U. campestris_, L., and _U. montana_, Burch, both from Europe. They attain a height of 40 metres by 1 metre in diameter, and grow well on cool gravelly soil. The elm in general is more suited to the hills or declivities than to the plains. It is very hardy and long-lived. Its timber is excellent for coach-building, and some parts of it for cabinet-making. It is a good species for stock, in suitable places, in the 3rd, 5th, 6th and 7th and some parts of the 9th region. It is sown as soon as the seeds ripen on well-tilled soil, either in furrows or plots. EXOTIC FOREST TREES WHICH IT WOULD BE WELL TO INTRODUCE FIR TREE.—The most interesting species are:— _A. amabilis_ and _A. balsamea_, from North America, grows from 30 to 40 metres high by 1 to 1·50 metres in diameter. Suitable for the 3rd, 5th and 6th regions. _A. bifida_, _A. brachyphylla_, from Japan, attain a height of 40 or 50 metres, 4th, 5th and 7th regions.