Rose: Roses are a common prickly plant with thorns on their stems to keep animals from nibbling. The spines of roses are needle-like or flattened and are usually brown or dark green in color.
Cactus: The cactus is also a common prickly plant with thorns on its stems that are used to prevent water evaporation and protect itself. The spines of cacti are usually elongated and yellowish or white in color.
Saponaria: The stems of Saponaria are also covered with thorns, which are usually conical in shape and brown or gray in color. The thorns of soaphorn can be used to make soap or cleaning products.
Goji berries: Goji berries also have thorns on their stems, which are usually small and yellow or green in color.
Agave: The stems of agave are also covered with spines, which are usually flattened and grayish-green or yellowish in color.
In addition to these plants, there are many other thorny plants such as some succulents, vines, and herbaceous plants, etc. The spines of these plants are usually evolved to defend themselves or adapt to their environment.
First of all, the spines on the stems act as a defense against the animal from gnawing. Some plants have sharp spines that can puncture the animal's mouth or **, thus protecting themselves from being eaten by animals. In addition, some spines can also secrete toxic substances that can poison animals and thus better protect themselves.
Secondly, the spines on the stems also reduce water evaporation and acclimatization to arid environments. In arid environments, plants need to retain water, and thorns can effectively reduce water evaporation, allowing plants to survive better in arid environments.
In addition, some of the spines can also help the plant cling to other objects, allowing them to better adapt to the environment.
In addition, the thorns of some plants can also play a role in reproduction. For example, the spines of a cactus are formed by the degeneration of leaves, and there is a certain pattern in the position and shape between the spines that can help the cactus reproduce.
In conclusion, the thorns on the stem of the plant are an evolutionary way for plants to adapt to their environment and defenses, and different plants have different shapes, sizes, and colors of spines, and they also serve different purposes.