Malus or seventh tree, or limbs of a crab tree are grafted onto some of the apple trees. In emergencies, a bucket or drum bouquet of crabapple flowering branches are placed near the beehives as orchard pollenizers. See also Fruit tree pollination. Because of the plentiful blossoms and small fruit, crabapples are popular for use in bonsai culture. Crabapple fruit is not an important crop in most areas, being extremely sour due to malic acid (which like the genus derives from the Latin name "mālum"), and in some species woody, and for this reason is rarely eaten raw. In some southeast
Étienne-Louis Malus Étienne-Louis Malus Étienne-Louis Malus (; ; 23 July 1775 – 24 February 1812) was a French officer, engineer, physicist, and mathematician. Malus was born in Paris, France. He participated in Napoleon's expedition into Egypt (1798 to 1801) and was a member of the mathematics section of the Institut d'Égypte. Malus became a member of the Académie des Sciences in 1810. In 1810 the Royal Society of London awarded him the Rumford Medal. His mathematical work was almost entirely concerned with the study of light. He studied geometric systems called "ray systems", closely connected to Julius Plücker's "line geometry". He conducted