The scientific classification of Black Walnut and Oatgrass 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. Black Walnut and Oatgrass kingdom and all other plants kingdom is Plantaea.
Plant family is the group of plants which have something in common. Black Walnut and Oatgrass family is a major factor of Black Walnut and Oatgrass 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. Black Walnut belongs to the family Juglandaceae and Oatgrass belongs to the family Poaceae.
While comparing scientific classification, Black Walnut and Oatgrass genus and other classification are also important. Also, when you compare Black Walnut and Oatgrass, other factors should also be taken into considerations like order, subfamilies, tribe, clade etc. First plant's genus is Juglans and other plant's genus is Danthonia. Black Walnut tribe is Juglandeae and Oatgrass tribe is Aveneae. Black Walnut clade is Angiosperms, Eudicots and Rosids and order is Juglandales whereas Oatgrass clade is Angiosperms, Commelinids and Monocots and order is Poales. Every plant have subfamilies. Black Walnut subfamilies are, Juglandinae and Oatgrass subfamilies are Danthonioideae. In this way you can compare scientific classification of Black Walnut and Oatgrass and other products also.