Acacia

Acacia trees were used as raw material for the construction of the Tabernacle and for the building of its utensils: the Ark of the Covenant, the Altar and the Table and the Pillars of the Curtain.
“And you shall make upright boards for the tabernacle of acacia wood. Ten cubits shall be the length of a board, and a cubit and a half shall be the breadth of one board.” (Exodus XXVI, 15-16
“And Bezalel made the ark of acacia wood; two cubits and a half was its length, and a cubit and a half its breadth, and a cubit and a half its height; And he overlaid it with pure gold inside and outside, and made a rim of gold around it. … And he made poles of acacia wood, and overlaid them with gold. (Exodus XXXVII, 1-2, 4)
Their length was certainly impressive. “Ten cubits shall be the length of a board, and a cubit and a half shall be the breadth of one board.”
In Isaiah’s vision of the flowering of the desert wilderness, the acacia features with non-desert trees:
“I will plant in the wilderness the cedar, the acacia tree, and the myrtle, and the oil tree;” (Isaiah XLI, 19).
Since acacia trees grow in the desert and the Children of Israel needed them for building purposes while they were in the desert, it is reasonable to assume that the identification is correct.

A genus that contains some 750 types of tree and shrub, whose spread covers tropical and sub-tropical regions. The origin of the name is the Greek word for thorn and hints at the spikiness of its members. The branches of the genus’ trees grow long, sharp and particularly hard in the Negev. Many species in Israel are fast-growing but short-lived evergreens. The leaf is doubly pinnate, having many leaflets. The flowers are minuscule, the calyx is bell-shaped and the corolla is small and not prominent. The stamens are long and colored. The flowers are arranged in multi-flowered inflorescence. The pod of the fruit either opens or is un-openable, mainly cylindrical or oblate.
Many species are ornamental and utilitarian trees from which many materials and products are extracted: medicines, raw materials for paint, perfumes, charcoal used to be prepared from the resin and it was also a source of food for the flock.

Three species grow in the Land of Israel in the desert and one rare species in the Mediterranean region. In large areas of the desert lands of the Negev and Sinai, acacia trees are the only trees. More than 20 ornamental species, originating from Africa and Australia, are also grown in the country.
The Australian acacia is characterized by large, flat leaves (being an expansion of the leaf petiole, as the true pinnate leaves degenerated).
Keren Kayemeth LeIsrael plants a number of acacia species, both local and acclimatized, mainly in arid areas: the Negev, around Maaleh Adumim, the Jordan Valley.