Cobb County Cooperative Extension

Weed of the Month

Weed Trees: Mimosa and Princess Tree

Cornelius Tarver

Horticulture Programs Assistant

Mimosa trees, Albizia julibrissin, and Princesstree, Paulownia tomentosa, are two familiar trees in the natural landscape. Neither is native to Georgia or North America, but both have naturalized throughout the state of Georgia. Because of their adaptability to a wide variety of soil conditions and extremely high seed rates Mimosas and Princesstrees can be found sprouting almost anywhere. Mimosas and Princesstrees are considered “weed” or “scrub” trees because of that characteristic.  But Mimosas and Princesstrees do both have attractive flowers and a few other desirable qualities though they are rarely sold by the nursery industry.

Mimosa, also known as silktree, originated in Asia. In North America it’s adapted to zones 6 – 9 and a wide variety of soil conditions. Mimosa has a fast growth rate with a mature height of 15 to 25 feet and a 25 – 35 foot spread. Mature trees have a spreading or vase shape. Leaves are doubly compound, resembling a fern, and the bark is thin. Mimosa wood is very brittle and breaks easily. Mimosa is highly susceptible to vascular wilt also called Mimosa wilt which can be fatal. It’s a short-lived tree with a lifespan of only 10 – 20 years.

Mimosa produces very showy, pink and white, feather like, slightly fragrant flowers in the spring and summer. If used in the landscape it may need pruning to train it into a single stem or multi-trunk tree and to improve its structure. Mimosa is deciduous and due to leaf litter and seed capsules they can be very messy trees. Mimosa takes full sun and tolerates drought. They are also deer resistant and don’t attract wildlife. Mimosas can grow in waste places and are good trees for reclaiming disturbed soils.

Princestree, also called empresstree and Royal Paulownia, is also a native of Asia. It’s become well adapted to the eastern United States in zones 5 – 9. It grows in sun or part shade and tolerates a wide range of soils but prefers moist deep well drained soils. Princestree has a rapid growth rate reaching upto 60 feet with a 20 – 30 foot spread and a two foot diameter trunk. The wood is brittle and its abundant seed capsules and leaf litter make it a very messy tree.

Princesstrees are recognizable by their large, hairy, heart shaped leaves upto 12 inches long and wide.

In April and May, they produce showy, fragrant, cone shaped, pale-violet, flower clusters before the leaves appear. They are rarely planted in the landscape but can be used to create dense shade quickly. They’re also deer resistant. They’re wood is used for furniture in Japan. In the United States they’re sometimes planted in groves to reclaim eroded soils.

  References:

 Albizia julibrissin, Mimosa, Edward F. Gilman and Dennis G. Watson. US Forest Service factsheet ST-68 November 1993.

Pricestree, Paulownia Paulownia tomentosa, (Thunb.) Sieb. & Zucc. ex Steud. US Forest Service Southern Research Station Headquarters factsheet.

Photos:

Mississippi State University Arboretum.

Western Carolina University, Peggy Buck 2003.

Trees of Reed College, Portland, Oregon.