Pecan "fruit of the walnut". They noted the particularly thin shell and acorn-like shape of the fruit, indicating they were indeed referring to pecans. The Spaniards took the pecan into Europe, Asia, and Africa beginning in the 16th century. In 1792, William Bartram reported in his botanical book, "Travels", a nut tree, "Juglans exalata" that some botanists today argue was the American pecan tree, but others argue was hickory, "Carya ovata". Pecan trees are native to the United States, and writing about the pecan tree goes back to the nation's founders. Thomas Jefferson planted pecan trees, "C. illinoinensis" (Illinois nuts), in
Fruit tree pruning and training can also prevent later injury from weak crotches or forks (where a tree trunk splits into two or more branches) that break from the weight of fruit, snow, or ice on the branches. Some sustainable agriculture or permaculture personalities, such as Sepp Holzer and Masanobu Fukuoka, advocate and practice no-pruning methods, which runs counter to the widespread confidence in the idea that pruning produces superior results compared with not pruning. Many books about fruit-growing assert advantages and disadvantages of pruning or not pruning, although without randomized controlled trials, it is hard to separate theorizing and traditional knowledge from