• Maples are perennial trees known for the syrup they produce.Jupiterimages/Photos.com/Getty Images
  
  Perennials are plants that live longer than one year, as opposed to annuals and biennials, which only live for one and two years, respectively. Nearly every tree fall under the category of perennials, including evergreens and deciduous species. A variety of plants are perennial as well, such as the monocarpic bamboo plant as well as herbaceous grasses and ferns.
  
  

Evergreen

• Evergreen perennials usually refer to trees who do not lose their foliage during the fall and winter. However, leaves will fall off evergreen trees, but only because new ones are replacing them. Evergreen trees include oak, conifer, rain forest species. Oak trees are gymnosperms, which means their seeds are exposed, or "naked." The seeds on these trees grow on the end of branches. Conifers are also gymnosperms, but their seeds are within cones. The seeds on forest species, such as magnolias and eucalypts, are enclosed in the tree's flowers and fruits. Thus, these type of trees are angiosperms.
  
  

Deciduous

• Although deciduous and evergreen trees are both perennials, deciduous trees differ from evergreens since they lose their foliage in the fall and winter months. The process of a tree losing its leaves is abscission. However, new leaves grow on the tree in the spring and summer months. Some deciduous trees are semi-evergreen, meaning not all of their leaves fall during the fall and winter. Examples of deciduous trees include maple, elm, aspen and birch. Although their leaves fall, their flowers may blossom during the process of abscission, and it is easier for winds to carry pollen from the flower in this time period.
  
  

Monocarpic

• The definition of monocarpic plants is a plant that only flowers once. After the plant flowers, it pollinates, spreads it seeds and dies. However, what makes these plants perennial is that it takes years for these plants to flower. Some monocarpic perennials include the Century Plant -- which belongs in the Agave genus-some species of yucca plants and bamboo. Certain species of bamboo plants live up to 100 years before they flower, according to the University of Illinois-Chicago. In cultivation, monocarpic plants can survive flowering if cultivators remove the flowers before they seed.
  
  

Herbaceous

• Herbaceous perennials usually refer to small plants with no permanent woody stalk, says Texas Tech University. Once they have flowered, these perennials reduce themselves to soil level during the fall and winter. However, the root system does not die and when it is time to grow again, herbaceous plants repeated the growing cycle. Herbaceous perennials include most grasses, ferns, hosta and mint plants. Out of all the perennial plants, herbaceous is the only plant category that includes annuals and biennial species.