The scientific classification of Trichocereus and Echeveria includes the entire classification chart that includes kingdom, family, clade, tribe etc. A kingdom is the second highest taxonomic rank. A taxonomic rank is the level that a living organisms are placed in hierarchical level of arrangement of life forms. All the living organisms are divided into kingdoms. Plant kingdom is a main classification of living organisms that include all plants. There are six kingdoms which are: Plantae, Animalia, Fungi, Protista, Aschaea/Archaeabacteria and Bacteria Eubacteria. Trichocereus and Echeveria kingdom and all other plants kingdom is Plantaea.
Plant family is the group of plants which have something in common. Trichocereus and Echeveria family is a major factor of Trichocereus and Echeveria Scientific Classification. Plant family helps you narrow the search of your plants. It also gives you idea about, how the plant looks, how the seed will be like etc. These two plant families can be different or same. Trichocereus belongs to the family Cactaceae and Echeveria belongs to the family Crassulaceae.
While comparing scientific classification, Trichocereus and Echeveria genus and other classification are also important. Also, when you compare Trichocereus and Echeveria, other factors should also be taken into considerations like order, subfamilies, tribe, clade etc. First plant's genus is Echinopsis and other plant's genus is Echeveria. Trichocereus tribe is Trichocereeae and Echeveria tribe is Sedeae. Trichocereus clade is Angiosperms, Core eudicots and Eudicots and order is Caryophyllales whereas Echeveria clade is Angiosperms, Core eudicots and Eudicots and order is Saxifragales. Every plant have subfamilies. Trichocereus subfamilies are, Cactoideae and Echeveria subfamilies are Sedoideae. In this way you can compare scientific classification of Trichocereus and Echeveria and other products also.