Question
I have conflicting answers from different local arborists and would appreciate a third independent answer.

I purchased, from an internet-based mail order nursery, several weeping willow saplings which I planted about 3 years ago.  The company sells both weeping willows and something called "hybrid" willows.  The photos of the weeping willows on the website look just like one would expect - round crowns with drooping branches.  The hybrids, however, resemble bushes that grow with vertical branches.  The 42 trees that I planted all have up-arcing branches and the crown comes to a point.  None of the branches weep in any way shape or form.  Additionally, some of the saplings have had exponential growth and what started as a 3' 1/4" sapling is now a 15'+ tree with a trunk diameter in excess of 5".  Furthermore, if I don't keep up with them, they keep developing offshoots of the bottom of the trunks.  One arborist tells me these are some type of a willow but are not a weeping willow; another arborist tells me that "weeping willow" is a generic term and that the trees, with proper pruning,will weep.  Not one of 42 trees are displaying any weeping activity.  What do you think?  Do willows started from saplings need to be pruned and trained to weep or should this occur naturally?

Answer
Hybrid willows are crosses between two or more different willow species or cultivars. These crosses are referred to as hybrid willows and tend to be more vigorous than their parents. Hybrid willows will exhibit traits of the different parents and is a way for plant breeders to introduce something like variegated leaves or fast growth to a weeping form. It takes years of experimentation and testing---the growth rate, hardiness and growing requirements are tested---before a willow hybrid is available for sale.



When you see plant catalogs advertising fast-growing hybrid willows for erosion control, windbreaks and privacy screens, you are looking at a hybrid of Salix alba, or white willow. There are several Salix alba crosses available to gardeners, although all are sold under the name hybrid willow. These hybrids are extremely fast-growing, often growing 6 to 10 feet a year. The fastest growth occurs in the first five years after planting, with the plant reaching maturity between five and seven years. These willow hybrids are suited for hedges, windbreaks or privacy screens because they have close-growing branches that start at the base of the plant and an upright growth habit. You can turn one of these crosses into a specimen tree; however, they typically don't have the graceful arching branches of species willows.

The other types of willow hybrid most commonly available are weeping-form descendants of species weeping willows. These trees have the arching branches of their parents and make excellent specimen trees.


The problem comes with common names--Hybrid willow, weeping willow, white willow ect. A true weeping willow is Salix babylonica.  Hybrid wilows are crosses between two wilows some maybe weeping. Over 400 species of willow (genus Salix# have been recorded and the species is very cross-fertile, leading to the establishment of many hybrid varieties of the species.  A well-known ornamental example is the Weeping Willow #Salix ?sepulcralis#, which is a hybrid of Peking Willow #Salix babylonica# from China and White Willow #Salix alba) from Europe.

I am not sure this answers your question but about the only way to make sure is from the species tag when the tree is bought IF it includes a scientific name. The tree will either weep or not depending on the species or cross you have. It will not grow into a weeping form. In three years you should have seen a weeping form if it were a true weeping willow.