Shrubs adapt to their environments in a variety of ways, among them by developing prickly leaves or stems. Sharp, thorny foliage helps prevent browsing by deer, rabbits or other wildlife that like to dine on landscape plants. Thorns help keep wildlife and humans from trampling on shrubs. Prickly shrubs can also serve as protective shelters for small, beneficial wildlife.

...
Wild rose shrubs have attractive flowers -- and prickly thorns.

Hawthorns

The many varieties of hawthorns (Crataegus spp.) can be grown as tall shrubs or small trees. Hawthorns have 1- to 3-inch thorns on their stems. These dense shrubs provide habitat and food for nesting birds. Hawthorns are native to North America and grow best in full sun to partial shade and moist, well-drained soil. Most varieties produce white flowers in mid-spring followed by small, red, bird-attracting fruits.

Wild Rose

The wild rose (Rosa carolina), a woody shrub, blooms from late spring through fall with fragrant, pink and purple blossoms. Flowers are followed by large, edible, red hips that last through winter. Wild rose thorns are most pronounced on larger stems. This spreading shrub grows up to 3 feet tall with a spread up to 12 feet wide. Wild rose shrubs prefer full sun and moist, well-drained soil, but tolerate wet, dry or alkaline sites.

Southern Blackberry

Like the wild rose, the Southern blackberry (Rubus argutus) grows only a few feet tall but can spread more than 10 feet wide. These quick-growing bushes have spiny, arching stems. Southern blackberries produce white to pink flowers in early summer, followed by large, edible fruits in late summer and fall. Southern blackberries can thrive in full sun to shade and prefer moist, well-drained soil.

Japanese Rose

The multiflora or Japanese rose (Rosa multiflora) grows 3 to 8 feet tall and spreads quickly from 10 to 15 feet wide, sometimes even growing over the top of other plants. This deciduous shrub has bright green foliage that turns yellow in fall, and thorny stems. Japanese roses produce fragrant, white blossoms in late spring followed by red hips in late summer. Plant this shrub in full sun and well-drained soil. Multiflora roses can tolerate salt spray and alkaline soils.

Catclaw Acacia

The catclaw acacia (Acacia greggii) is a large shrub native to the southwestern United States. Catclaw acacia can grow to 15 feet tall with a 25-foot spread. This shrub has large, twisted, extremely sharp thorns and gray-green deciduous foliage. The catclaw acacia blooms in spring with aromatic spikes of yellow blossoms that grow into flat, brown seed pods. Plant this drought-tolerant shrub in well-drained soil and full sun. Though this shrub is suitable for xeriscaping, irrigate regularly for the best results.