White hawthorn, commonly called white haw or dotted hawthorn, is native to the eastern United States and Canada. It is a medium-size tree and part of the Rosaceae family of plants. It is identified under the species name Crataegus punctata and produces the state flower of Missouri.
The tree can grow 20 to 30 feet (about 6 to 9 m) tall with an equal canopy spread. White hawthorn is a deciduous tree, shedding its leaves in late fall and remaining bare through the winter. The tiny, snow-white 0.5 inch (about 1.7 cm) diameter flowers bloom in late spring and are followed by small, round 0.75 inch (about 1.9 cm) fruit in summer.
Hawthorn trees, including white hawthorn, belong to the Rosaceae family and are closely related to apples, pears, cherries, peaches and apricots. Unlike their edible relatives, hawthorn fruits are considered ornamental due to their small size, hardness and general unpalatability for humans. Hawthorn fruits do provide an important food source for birds and mammals, however.
White hawthorn grows best in a spot in full sun. It can be pruned into a small landscape tree or allowed to reach its mature height and spread, providing shade in summer and fall. Like other hawthorns, white hawthorn has sharp spines on the branches.
As an ornamental landscape tree, white hawthorn is ideal for providing both lush green foliage, abundant late spring blossoms and ornamental summer and fall fruit. It also provides shade and visual interest. It can also be planted as part of a screen planting or planted and pruned to retain a hedge shape. Tolerant of urban conditions, white hawthorn is also well suited for lining city streets and parking areas.
Spring is the best time to plant a new white hawthorn in the landscape, as it will have the whole summer to get established before winter. Fall panting is also suitable, though, depending on how the hawthorn tree arrived from the nursery. Ornamental trees, for instance, tend to come in nursery pots with a soil ball around the roots, often wrapped in a burlap sack. Potted hawthorns and those with a soil ball wrapped in burlap can be planted any time between spring and fall. Bare root trees have the best chance of success when planted in spring.
Pruning should be done in late winter or early spring before the new leaf buds appear. All dead wood and broken branches should be removed using pruning shears for smaller branches and a tree saw for larger branches. The trees can pruned to maintain the desired shape and size.