The term that's synonymous with phylum, in the plant world, is division. So the phylum, or preferentially the division, of cactus plants is Magnoliophyta. It's the division for angiosperms, which also are called flowering plants. Flowering plants may develop from an embryo that has one or two leaves. A cactus is a dicotyledon, because it has two embryonic leaves.
Tracheophyta is the phylum in which the saguaro cactus [Carnegiea gigantea] is found. It's the phylum of the tracheophytes, which also are called higher or vascular plants. These plants have specialized tissues for moving around water, minerals and dissolved nutrients, and energizing products from the photosynthetic interaction with sunlight.
filicinophyta
Plants in the phylum Coniferophyta are gymnosperms.
Plants in the phylum Coniferophyta are gymnosperms.
Cactus, like other plants, uses photosynthesis to get energy.
Plants are classified by divisions rather than by phylum. The phylum is very broad and may be quite confusing in classification of the plants.
Cactus
Plants do not have a phylum because a phylum is whether a living thing has a backbone or not.
Cactus plants use their stems for storage. So that's where starches are stored. In fact, stems are where a cactus plant stores everything. Other, non cactus plants may use their roots for storage. But cactus roots are much too fibrous and shallow.
A cactus competes with other plants for water.
The cactus wren
Classification of Cacti:Kingdom - Plantae (plants)Phylum - Tracheophyta (vascular plants)Division - MagnoliophytaClass - DicotyledonaeSubclass - CaryophyllidaeOrder - CaryophyllalesFamily - Cactaceae (cacti)Genus - About 100 genera and 1000-2000 species divided into three tribes