Phosphorus, Nitrogen, and Potassium
rice, wheat, and corn
rice, wheat, and corn.
the three sisters ;)
the three sister....APEX
Hay, soybeans, and corn are the top three economically important crops in Virginia.
The growth of crops in response to certain fertilizers.
turkey,corn,squash,duck,men
The topsoil, which is where most root growth occurs, is the most important layer for growing crops.
The most important application is as fertilizers in agriculture.
It's not entirely true to say, "...regularly add nitrate fertilizers..." since farmers in the US generally select the kind of fertilizers to use based on the nutrient needs of the crop, timing of application, and price of the fertilizer material. Nitrate fertilizers are one form they can use to get nitrogen, possibly the single most important nutrient, to their crops. However, nitrates are not always the most appropriate form to use, and so they also use ammonium types such as urea or anhydrous ammonia.
Early settlers in Oklahoma grew sugar cane, cotton, and wheat.
corn, beans, and squash (APEX)