The flowers, which are clear white, grow in clusters. There are from six to twenty of these clusters on a tree, each of which produces a bunch of dates. The female tree bears the fruit. The blossoms are pollinated both by the wind and by man. There are from ten to fifteen pounds of dates in a bunch. A tree will average from one hundred to two hundred pounds each year, although trees have been known to yield six hundred pounds. The trees yield when from four to eight years old, and continue to bear for a century. The dates, green at first, later in the year a yellowish brown, are, when ripe, amber or black in color. The trees require a very dry, hot climate, but moist soil. Long, long ago, this saying was common among the Arabs, "The date palm, the queen of trees, must have her feet in running water and her head in the burning sky." Although there are lovely date palm trees on the grounds of many California homes, few of them bear fruit. The temperature must average from eighty to ninety degrees for a considerable time in the summer, in order to mature it. What is the average summer temperature in your locality? If an ordinary tree is frost-bitten, it recovers and soon puts out a new growth; but if the crown of the date palm be frozen, the tree dies. When the Moors went to Spain, in the eleventh century, they introduced this valuable tree which the mission fathers several hundred years later brought to Mexico and to Southern California. How would you like to try to climb a date palm tree? Although they look so smooth and are without branches, the natives of the desert climb them without any help whatever. The trunk is always somewhat rough, and this makes it possible to ascend them. [Illustration: FIG. 55.--Date Palm Trees.] Not all of the dates in a bunch ripen at once, so they are usually picked by hand and only the ripe ones selected. Sometimes, however, the bunches are cut off. Some dates contain so much sap that the bunches must be hung up to allow it to drain off before they can be shipped. This sap is called _date honey_, and is saved. They are sent to the coast towns in bags or boxes called _frails_. Where dates are to be sold in small quantities, they are repacked in the small boxes such as you have seen. You know that dates are very sweet, and it is no wonder that they are, for they contain from fifty-five to sixty per cent of sugar. The trees are often tapped, and the sap which flows out is made into sugar. Vinegar and a liquor called _arrack_ are also made from it. The leaves of the tree are made into bags and mats; from the stones a drink is made which takes the place of coffee. From the leafstalks baskets are made, while the trunk furnishes material for houses and for fences.