Juglans nigra English or Persian walnut, but thrives best in the warmer regions of fertile, lowland soils with high water tables, although it will also grow in drier soils, but much more slowly. Some soils preferred by black walnut include Alfisol and Entisol soil types. Walnut grows best on sandy loam, loam, or silt loam type soils but will also grow well on silty clay loam soils. It prefers these soils because they hold large quantities of water which the tree draws from during dry periods. Visually, black walnut is similar to the butternut ("Juglans cinerea") in leaf shape, and the range
Fruit tree pollination a pollinator tree. Working from an old Spanish variety, "Tuono", researchers in 2008 started making available new self-fertile varieties that more closely match the qualities of the popular "Nonpareil" almond—including varieties "Lone Star" and "Independence". While self-fertile trees do not require pollen from a second tree variety for fruit / nut set, they still depend upon insect pollination for good production. Almond growers with self-fertile almonds report excellent nut set with half (or less) the number of bees in the field. Like apples, pears are self-incompatible and need to attract insects in order to be pollinated and produce fruit. One