The scientific classification of Adam's Needle and Bouteloua Gracilis 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. Adam's Needle and Bouteloua Gracilis kingdom and all other plants kingdom is Plantaea.
Plant family is the group of plants which have something in common. Adam's Needle and Bouteloua Gracilis family is a major factor of Adam's Needle and Bouteloua Gracilis 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. Adam's Needle belongs to the family Agavaceae and Bouteloua Gracilis belongs to the family Poaceae.
While comparing scientific classification, Adam's Needle and Bouteloua Gracilis genus and other classification are also important. Also, when you compare Adam's Needle and Bouteloua Gracilis, other factors should also be taken into considerations like order, subfamilies, tribe, clade etc. First plant's genus is Yucca and other plant's genus is Bouteloua. Adam's Needle tribe is Not Available and Bouteloua Gracilis tribe is Cynodonteae. Adam's Needle clade is Angiosperms and Monocots and order is Liliales whereas Bouteloua Gracilis clade is Angiosperms, Commelinids and Monocots and order is Cyperales. Every plant have subfamilies. Adam's Needle subfamilies are, Agavoideae and Bouteloua Gracilis subfamilies are Chloridoideae. In this way you can compare scientific classification of Adam's Needle and Bouteloua Gracilis and other products also.